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In recent decades, the volume of scholarly literature worldwide has increased significantly, and open-access publishing has become commonplace. These changes are even more dominant in South Korea. Comparing the periods of 1981-2000 and 2001-2020, the number of medical articles produced in Korea increased by 16.8 times on the Web of Science platform (13,223 to 222,771 papers). Before 1990, almost no open-access articles were produced in South Korea, but in the last 10 years open-access publications came to account for almost 40% of all South Korean publications on Web of Science. Along with the expansion of literature and the development of open-access publishing, predatory journals that seek profit without conducting quality assurance have appeared and undermined the academic corpus. In this rapidly changing environment, medical researchers have begun contemplating publication standards. In this article, recent trends in academic publishing are examined from international and South Korean perspectives, and the significance of open-access publishing and recent changes are discussed. Practical methods that can be used to select legitimate publishers, including open-access journals, and identify predatory journals are also discussed. [ABSTRACT FROM AUTHOR]

Purpose We investigated the proportions of patients eligible for accelerated partial breast irradiation (APBI) among those with pT1- 2N0 breast cancer, based on the criteria set by the American Society for Radiation Oncology (ASTRO), the Groupe Européen de Curiethérapie and the European Society for Radiotherapy and Oncology (GEC-ESTRO), the American Brachytherapy Society (ABS), and the American Society of Breast Surgeons (ASBS). Additionally, we analyzed the rate of APBI utilization among eligible patients. Materials and Methods Patients diagnosed with pT1-2N0 breast cancer in 2019 were accrued in four tertiary medical centers in Korea. All patients had undergone breast conserving surgery followed by radiotherapy, either whole breast irradiation or APBI. To determine which guideline best predicts the use of APBI in Korea, the F1 score and Matthews correlation coefficient (MCC) were determined for each guideline. Results A total of 1,251 patients were analyzed, of whom 196 (15.7%) underwent APBI. The percentages of eligible patients identified by the ASTRO, GEC-ESTRO, ABS, and ASBS criteria were 13.7%, 21.0%, 50.5%, and 63.5%, respectively. APBI was used to treat 54.4%, 37.2%, 27.1%, and 23.7% of patients eligible by the ASTRO, GEC-ESTRO, ABS, and ASBS criteria, respectively. The ASTRO guideline exhibited the highest F1 score (0.76) and MCC (0.67), thus showing the best prediction of APBI utilization in Korea. Conclusion The proportion of Korean breast cancer patients who are candidates for APBI is substantial. The actual rate of APBI utilization among eligible patients may suggest there is a room for risk-stratified optimization in offering radiation therapy. [ABSTRACT FROM AUTHOR]

Purpose This study assessed the temporal trends of uptake of national general health and cancer screening among women with breast cancer in Korea between 2009 and 2016. Materials and Methods We retrospectively analyzed the claims data from the Korean National Health Insurance Service database. Participants included 101,403 breast cancer patients diagnosed between 2009 and 2016. Information on participation in national screening programs, including breast cancer screening, general health, and gastric, colorectal, and cervical cancers, up to 2020 was collected. Screening participation rates within the first 2 and 5 years postdiagnosis were calculated by diagnosis year and fitted with joinpoint regression models to assess temporal trends. Results Overall, the participation rate in breast cancer screening within 2 years postdiagnosis increased from 10.9% to 14.0% from 2009-2016, with an annual percentage change (APC) of 3.7% (p < 0.05). The participation rate in breast cancer screening was lower than that in general health checkup and screening for other cancers within 2 and 5 years postdiagnosis. A steady increase in screening trends was also observed for general health, gastric, colorectal, and cervical cancers, with APC of 5.3%, 5.7%, 6.9%, and 7.6% in the 2-year postdiagnosis rate, and APC of 3.6%, 3.7%, 3.7%, and 4.4% in 5-year postdiagnosis rate, respectively. The screening rate was highest among age groups 50-59 and 60-69 in 2009 and significant upward trends were observed in all age groups for general health checkup and gastric, colorectal, and cervical cancer screening. Conclusion Among female breast cancer survivors in Korea, the uptake rate of screenings for general health and various cancers, including breast, gastric, colorectal, and cervical cancers, has shown a gradual increase in recent years. [ABSTRACT FROM AUTHOR]

Purpose Programmed death-1 blockade with pembrolizumab has shown promising activity in relapsed/refractory (R/R) extranodal natural killer/T-cell lymphoma (NKTCL), but studies are limited, with small patient numbers. Materials and Methods Thirteen institutes involved with the Consortium for Improving Survival of Lymphoma, a Korean lymphoma study group, collected the clinical data of 59 patients treated with pembrolizumab as salvage therapy between 2016 and 2022. Results The median age of the patients was 60 years (range, 22 to 87 years), and 76.3% had advanced Ann Abor stage disease. Pembrolizumab was given to 35.6%, 40.7%, and 23.7% of the patients as second-, third-, and fourth- or higher-line chemotherapy, respectively. The overall response rate was 40.7%, with 28.8% having complete response. The estimated 2-year progression-free survival (PFS) and overall survival rates for all patients were 21.5% and 28.7%, respectively; for responders, the rates were 53.0% and 60.7%, respectively. Although not statistically significant, Eastern Cooperative Oncology Group performance status = 2 (hazard ratio [HR], 1.91; 95% confidence interval [95% CI], 0.93 to 3.94; p=0.078) and stage III or IV disease (HR, 2.59; 95% CI, 0.96 to 6.96; p=0.060) were associated with a trend toward shorter PFS in multivariate analysis. Grade 3 or 4 adverse events (AEs) were noted in 12 patients (20.3%); neutropenia (10.2%), fatigue (6.8%), and pneumonitis (5.1%) were most common AEs. Conclusion In conclusion, while pembrolizumab had a modest effect on patients with R/R NKTCL, it may be a useful salvage therapy for patients with localized disease and good performance status. [ABSTRACT FROM AUTHOR]

Purpose In men with metastatic castration-resistant prostate cancer (mCRPC), new bone lesions are sometimes not properly categorized through a confirmatory bone scan, and clinical significance of the test itself remains unclear. This study aimed to demonstrate the performance rate of confirmatory bone scans in a real-world setting and their prognostic impact in enzalutamide-treated mCRPC. Materials and Methods Patients who received oral enzalutamide for mCRPC during 2014-2017 at 14 tertiary centers in Korea were included. Patients lacking imaging assessment data or insufficient drug exposure were excluded. The primary outcome was overall survival (OS). Secondary outcomes included performance rate of confirmatory bone scans in a real-world setting. Kaplan-Meier analysis and multivariate Cox regression analysis were performed. Results Overall, 520 patients with mCRPC were enrolled (240 [26.2%] chemotherapy-naïve and 280 [53.2%] after chemotherapy). Among 352 responders, 92 patients (26.1%) showed new bone lesions in their early bone scan. Confirmatory bone scan was performed in 41 patients (44.6%), and it was associated with prolonged OS in the entire population (median, 30.9 vs. 19.7 months; p < 0.001), as well as in the chemotherapy-naïve (median, 47.2 vs. 20.5 months; p=0.011) and post-chemotherapy sub-groups (median, 25.5 vs. 18.0 months; p=0.006). Multivariate Cox regression showed that confirmatory bone scan performance was an independent prognostic factor for OS (hazard ratio 0.35, 95% confidence interval, 0.18 to 0.69; p=0.002). Conclusion Confirmatory bone scan performance was associated with prolonged OS. Thus, the premature discontinuation of enzalutamide without confirmatory bone scans should be discouraged. [ABSTRACT FROM AUTHOR]

Purpose The purpose of this study is to determine the level of health equity in relation to cancer incidence. Materials and Methods We used the National Health Insurance (NHI) claims data of the National Health Insurance Service between 2005 and 2022 and annual health insurance and medical aid beneficiaries between 2011 and 2021 to investigate the disparities of cancer incidence. We calculated age-sex standardized cancer incidence rates by cancer and year according to the type of insurance and the trend over time using the annual percentage change. We also compared the hospital type of the first diagnosis by cancer type and year and cancer incidence rates by cancer type and region in 2021 according to the type of insurance. Results The total cancer incidence increased from 255,971 in 2011 to 325,772 cases in 2021. The absolute difference of total cancer incidence rate between the NHI beneficiaries and the medical aid (MA) recipients increased from 510.1 cases per 100,000 population to 536.9 cases per 100,000 population. The odds ratio of total cancer incidence for the MA recipients increased from 1.79 (95% confidence interval [CI], 1.77 to 1.82) to 1.90 (95% CI, 1.88 to 1.93). Disparities in access to hospitals and regional cancer incidence were profound. Conclusion This study examined health inequities in relation to cancer incidence over the last decade. Cancer incidence was higher in the MA recipients, and the gap was widening. We also found that regional differences in cancer incidence still exist and are getting worse. Investigating these disparities between the NHI beneficiaries and the MA recipients is crucial for implementing of public health policies to reduce health inequities. [ABSTRACT FROM AUTHOR]

Purpose The female sex is reported to have a higher risk of adverse events (AEs) from cytotoxic chemotherapy. Few studies examined the sex differences in AEs and their impact on the use of medical services during adjuvant chemotherapy. This sub-study aimed to compare the incidence of any grade and grade = 3 AEs, healthcare utilization, chemotherapy completion rate, and dose intensity according to sex. Materials and Methods This is a sub-study of a multicenter cohort conducted in Korea that evaluated the impact of healthcare reimbursement on AE evaluation in patients who received adjuvant chemotherapy between September 2013 and December 2016 at four hospitals in Korea. Results A total of 1,170 patients with colorectal, gastric, or non-small cell lung cancer were included in the study. Female patients were younger, had fewer comorbidities, and experienced less postoperative weight loss of > 10%. Females had significantly higher rates of any grade AEs including nausea, abdominal pain, stomatitis, vomiting, and neutropenia, and experienced more grade = 3 neutropenia, nausea, and vomiting. The dose intensity of chemotherapy was significantly lower in females, and they also experienced more frequent dose reduction after the first cycle. Moreover, female patients receiving platinum-containing regimens had significantly higher rates of unscheduled outpatient visits. Conclusion Our study found that females experienced a higher incidence of multiple any-grade AEs and severe neutropenia, nausea, and vomiting, across various cancer types, leading to more frequent dose reductions. Physicians should be aware of sex differences in AEs for chemotherapy decisions. [ABSTRACT FROM AUTHOR]

Purpose This study aimed to report the projected cancer incidence and mortality for the year 2024 to estimate Korea's current cancer burden. Materials and Methods Cancer incidence data from 1999 to 2021 were obtained from the Korea National Cancer Incidence Database, and cancer mortality data from 1993 to 2022 were acquired from Statistics Korea. Cancer incidence and mortality were projected by fitting a linear regression model to observed age-specific cancer rates against their respective years and multiplying the projected age-specific rates by the anticipated age-specific population for 2024. A joinpoint regression model was used to determine the year in which the linear trend changed significantly; we only used the data of the latest trend for prediction. Results In total, 292,221 new cancer cases and 83,770 cancer deaths are expected to occur in Korea in 2024. The most common cancer site is expected to be the thyroid, followed by the colon and rectum, lung, breast, and stomach. These five cancers are expected to represent 55.7% of the overall burden of cancer in Korea. The most common type of cancer leading to death is expected to be lung cancer, followed by liver, colorectal, pancreatic, and stomach cancers. Conclusion The age-standardized incidence rates for female breast and prostate cancers are estimated to continue to increase. These up-to-date estimates of the cancer burden in Korea could be an important resource for planning and evaluating cancer-control programs. [ABSTRACT FROM AUTHOR]

Purpose The current study provides national cancer statistics and their secular trends in Korea, including incidence, mortality, survival, and prevalence in 2021. Materials and Methods Incidence, survival, and prevalence rates of cancer were calculated using the Korea National Cancer Incidence Database, from 1999 to 2021, with survival follow-up until December 31, 2022. Deaths from cancer were assessed using causes-of-death data obtained from Statistics Korea. Results The number of new cancer diagnoses in 2021 increased by 27,002 cases (10.8%) compared to 2020. In 2021, newly diagnosed cancer cases and deaths from cancer were reported as 277,523 (age-standardized rate [ASR], 289.3 per 100,000) and 82,688 (ASR, 67.6 per 100,000), respectively. The overall cancer incidence rates increased by 3.3% annually from 1999 to 2012, and decreased by 5.3% from 2012 to 2015, thereafter, followed by non-significant changes. Cancer mortality rates have been decreasing since 2002, with more rapid decline in recent years (annual decrease of 2.8% from 2002 to 2013; 3.2% from 2013 to 2021). The 5-year relative survival between 2017 and 2021 was 72.1%, which contributed to prevalent cases reaching over 2.4 million in 2021. Conclusion In 2021, the number of newly diagnosed cancer patients increased as healthcare utilization recovered from the coronavirus disease 2019-related declines of 2020. Revised cancer registration guidelines expanded the registration scope, particularly for stomach and colorectal cancer. Survival rates have improved over the years, leading to a growing population of cancer survivors, necessitating a comprehensive cancer control strategy. The long-term impact of the pandemic on cancer statistics requires future investigation. [ABSTRACT FROM AUTHOR]

Purpose We aimed to determine the current application and survival trends of hematopoietic stem cell transplantation (HSCT) among Korean children and adolescents with cancer. Materials and Methods Data of patients aged < 20 years with KCD-10 (Korean Classifications of Diseases, 10th revision) C codes and specific designation codes were collected from the National Health Insurance Service database. Thirty claim codes for HSCT were included, and data from 2009 to 2019 were analyzed. Results The operational definition of pediatric cancer yielded an annual average of 2,000, with annual cases decreasing. In 2019, 221 HSCTs were performed, a decrease from the ten-year average of 276. Allografts outnumbered autografts with a ratio of 1.5:1. The source of allograft was bone marrow in 15% of patients in 2009; however, it substantially decreased to 3.3% in 2019. Furthermore, 70.5% of allogeneic HSCT used peripheral blood stem cell (PBSC) grafts, which increased to 89.3% by 2015. Cord blood utilization markedly decreased to 2.7% in 2018. The 5-year overall survival (OS) rate of all patients was 85.1%. Overall mortality decreased among patients who underwent recent HSCT, and they exhibited a higher 5-year OS rate. Conclusion In Korea, the number of pediatric patients with cancer is declining; however, the ratio of transplants to all patients remains constant. Patients who recently underwent transplantation showed better survival rates, possibly due to HSCT optimization. Korea showed a substantially greater PBSC utilization in pediatric HSCT. An in-depth examination encompassing donor relations and cause of death with a prospective registry is required in future studies. [ABSTRACT FROM AUTHOR]

Purpose Li-Fraumeni syndrome (LFS) is a hereditary disorder caused by germline mutation in TP53. Owing to the rarity of LFS, data on its clinical features are limited. This study aimed to evaluate the clinical characteristics and prognosis of Korean patients with LFS. Materials and Methods Patients who underwent genetic counseling and confirmed with germline TP53 mutation in the National Cancer Center in Korea between 2011 and 2022 were retrospectively reviewed. Data on family history with pedigree, types of mutation, clinical features, and prognosis were collected. Results Fourteen patients with LFS were included in this study. The median age at diagnosis of the first tumor was 32 years. Missense and nonsense mutations were observed in 13 and one patients, respectively. The repeated mutations were p.Arg273His, p.Ala138Val, and pPro190Leu. The sister with breast cancer harbored the same mutation of p.Ala138Val. Seven patients had multiple primary cancers. Breast cancer was most frequently observed, and other types of tumor included sarcoma, thyroid cancer, pancreatic cancer, brain tumor, adrenocortical carcinoma, ovarian cancer, endometrial cancer, colon cancer, vaginal cancer, skin cancer, and leukemia. The median follow-up period was 51.5 months. Two and four patients showed local recurrence and distant metastasis, respectively. Two patients died of leukemia and pancreatic cancer 3 and 23 months after diagnosis, respectively. Conclusion This study provides information on different characteristics of patients with LFS, including types of mutation, types of cancer, and prognostic outcomes. For more appropriate management of these patients, proper genetic screening and multidisciplinary discussion are required. [ABSTRACT FROM AUTHOR]

Purpose BRCA1/2 mutations are well-known risk factors for breast and ovarian cancers in women. Risk-reducing salpingo-oophorectomy (RRSO) is the standard treatment for preventing ovarian cancer with BRCA mutations. Postmenopausal syndrome (symptoms after RRSO can be alleviated by hormone replacement therapy (HRT); however, the use of HRT in carriers of BRCA mutations has been controversial because of the concern that HRT increases the risk of breast cancer. This study aimed to evaluate the effects of HRT in BRCA mutation carriers who underwent RRSO. Materials and Methods A total of 151 carriers, who underwent RRSO between 2013 and 2020 after the diagnosis of BRCA1 or BRCA2 mutations were selected and followed up for a median of 3.03 years. Patients were divided into two groups: those who received HRT after RRSO (n=33) and those who did not (n=118). We compared the incidence of breast cancer over time between these two groups. Results There was no significant difference in the incidence of breast cancer between women who received HRT and those who did not (p=0.229). Multivariate logistic regression analysis, adjusted for age and parity revealed no significant difference in the risk of breast cancer between these two groups (hazard ratio, 0.312; 95% confidence interval, 0.039 to 2.480; p=0.278). Conclusion In this study, we found no relationship between post-RRSO HRT and breast cancer in the population with BRCA mutations. Therefore, healthcare providers may consider the alleviation of symptoms of postmenopausal syndrome through HRT in patients who underwent RRSO. [ABSTRACT FROM AUTHOR]

Purpose In the modern era of precision medicine, next-generation sequencing (NGS) is employed for a variety of clinical purposes. The aim of this study was to investigate the trends and clinical characteristics of NGS testing in South Korea. Materials and Methods This nationwide, population-based, retrospective cohort study examined National Health Insurance Service claims data from 2017 to 2021 for NGS and from 2008 to 2021 for gene-targeted anticancer drugs. Results Among the total 98,748 claims, there were 51,407 (52.1%) solid cancer panels, 30,173 (30.5%) hereditary disease panels, and 17,168 (17.4%) hematolymphoid cancer panels. The number of annual claims showed a persistent upward trend, exhibiting a 5.4-fold increase, from 5,436 in 2017 to 29,557 in 2021. In the solid cancer panel, colorectal cancer was the most common (19.2%), followed by lung cancer (18.8%). The annual claims for targeted cancer drugs have increased 25.7-fold, from 3,932 in 2008 to 101,211 in 2020. Drugs for the treatment of lung cancer accounted for 488,819 (71.9%) claims. The number of patients who received non-hereditary NGS testing has substantially increased, and among them, the count of patients prescribed targeted anticancer drugs consistently rose from 508 (13.9%) in 2017 to 2,245 (12.3%) in 2020. Conclusion This study highlights the rising nationwide demand for comprehensive genetic testing for disease diagnosis and treatment following NGS reimbursement by the National Health Insurance in South Korea, in addition to the need for greater utilization of targeted anticancer drugs. [ABSTRACT FROM AUTHOR]

Purpose The genetic attribution for pancreatic ductal adenocarcinoma (PDAC) has been reported as 5%-10%. However, the incidence of germline pathogenic variants (PVs) in Korean PDAC patients has not been thoroughly investigated. Therefore, we studied to identify the risk factors and prevalence of PV for future treatment strategies in PDAC. Materials and Methods Total of 300 (155 male) patients with a median age of 65 years (range, 33 to 90 years) were enrolled in National Cancer Center in Korea. Cancer predisposition genes, clinicopathologic characteristics, and family history of cancer were analyzed. Results PVs were detected in 20 patients (6.7%, median age 65) in ATM (n=7, 31.8%), BRCA1 (n=3, 13.6%), BRCA2 (n=3), and RAD51D (n=3). Each one patient showed TP53, PALB2, PMS2, RAD50, MSH3, and SPINK1 PV. Among them, two likely PVs were in ATM and RAD51D, respectively. Family history of various types of cancer including pancreatic cancer (n=4) were found in 12 patients. Three patients with ATM PVs and a patient with three germline PVs (BRCA2, MSH3, and RAD51D) had first-degree relatives with pancreatic cancer. Familial pancreatic cancer history and PVs detection had a significant association (4/20, 20% vs. 16/264, 5.7%; p=0.035). Conclusion Our study demonstrated that germline PVs in ATM, BRCA1, BRCA2, and RAD51D are most frequent in Korean PDAC patients and it is comparable to those of different ethnic groups. Although this study did not show guidelines for germline predisposition gene testing in patients with PDAC in Korea, it would be emphasized the need for germline testing for all PDAC patients. [ABSTRACT FROM AUTHOR]

Purpose We aimed to determine the trends in the use of radiotherapy (RT) and the expenses associated with it in South Korea. Materials and Methods The statistical data of the claims and reimbursement records provided on the Health and Insurance Review and Assessment Service website were utilized. This included information such as the number of patients, fractions, medical expenses according to treatment codes, in/outpatient, sex, age, and regions of hospitals. We analyzed data from 2016 to 2020. Results With a growing RT infrastructure and an increase in the number of radiation oncologists, the expenses for RT were 605.5 million USD in 2020, which had increased 1.5 times from 394.7 million USD in 2016. This growth was mainly because of the increased usage of advanced RT techniques. Furthermore, the proportion of intensity-modulated radiation therapy (IMRT) expenses in the total expenses increased by 1.6 times from 48.8% in 2016 to 76.9% in 2020. Advanced techniques were used more commonly in older individuals or children. However, the proportion of IMRT expenses increased mostly in young women. Additionally, geographical differences in RT use and expense were observed, although the gap in the IMRT fractions decreased among the regions. Conclusion Recent medical expenses associated with RT in Korea have increased in tandem with technological advances and changes in demographics. [ABSTRACT FROM AUTHOR]

Purpose This study aimed to evaluate the participation and follow-up test compliance rates and key performance indicators of the National Cancer Screening Program (NCSP) for colorectal cancer (CRC) from 2004 to 2017. Materials and Methods The overall outcomes of the NCSP for CRC were analyzed using the NCSP data collected from 2004 to 2017 and the Korean Central Cancer Registry for CRC from 2005 to 2017. We cross-sectionally analyzed the participation and follow-up test compliance rates and performance indicators for each year. The trend of participation rates as an annual percentage change was assessed, and other statistical analyses were performed. Results The screening participation rates increased from 7.3% in 2004 to 30.5% in 2017. Additionally, the screening rates were higher among individuals aged 60-69 years and National Health Insurance Service beneficiaries of low-income status. However, the adherence to the follow-up test decreased from 63% in 2004 to 32% in 2017. The follow-up tests using the double-contrast barium enema method decreased from 42.2% in 2004 to 0.3% in 2017. However, follow-up tests by colonoscopy increased from 21.0% in 2004 to 31.8% in 2017. Furthermore, the positivity, false-positive, and interval CRC rates decreased, whereas the specificity increased from 2004 to 2016, indicating improved performance of CRC. Conclusion The participation rates and performance of the NCSP for CRC have steadily improved, whereas adherence to follow-up tests has decreased. Additionally, there is a rapid growth in colonoscopy volume as a follow-up test. Continued efforts are required to improve the follow-up rates. [ABSTRACT FROM AUTHOR]

Purpose A three-drug combination of cyclophosphamide, bortezomib, and dexamethasone (CVD) shows significant efficacy and manageable toxicity as induction therapy in patients with multiple myeloma. Materials and Methods In this phase II study, we enrolled 45 patients who achieved a very good partial response (VGPR) or partial response (PR) after autologous stem cell transplantation (ASCT) and evaluated the efficacy and toxicity of CVD consolidation. CVD consolidation comprised three cycles of cyclophosphamide 300 mg/m2 orally on days 1, 8, and 15, and bortezomib 1.3 mg/m2 subcutaneously on days 1, 8, 15, and 22, along with dexamethasone 20 mg orally or intravenously on days 1 and 2, 8 and 9, 15 and 16, and 22 and 23. Results At enrollment, 39 patients (86.7%) showed VGPR, and nine (13.3%) presented with PR. Nineteen patients (45.2%) achieved a complete response or better as their best response after the end of consolidation. Overall, 22 of 42 patients (52.4%) experienced an improved response status with CVD consolidation. Three-year overall survival and progression-free survival rates were 89.0% and 42.7%, respectively. The most common non-hematologic toxicities were peripheral neuropathy and infection (20.5%), with no grade = 3 neuropathy observed. Conclusion These results showed that CVD consolidation therapy improved the response with reasonable toxicity in patients with residual disease after ASCT. This trial was registered with the Clinical Research Information Service, Republic of Korea (KCT0001327). [ABSTRACT FROM AUTHOR]

Purpose This study aimed to examine secular trends, age-period-cohort effects, and geographical differences in gastric cancer (GC) mortality in Korea. Materials and Methods Using cause of death data from the Korean Statistical Information Service for GC from 2000 to 2020, we calculated average annual percentage changes (AAPCs) in the age-standardized mortality of GC in 17 cities and provinces through joinpoint regression. Decomposition of age, period, and cohort effects on GC mortality were elucidated by applying a log-linear model and an intrinsic estimate method. Spatial patterns and the degree of spatial clustering in 250 administrative regions were explored via Moran's I statistics. Stratification by sex was performed for all analyses. Results The age-standardized mortality of GC per 100,000 persons declined from 29.0 in 2000 to 7.9 in 2020 (AAPC, -6.28%). Ageperiod-cohort analyses of GC mortality showed a downward trend among 5-year age groups from age 20-89 years across five-year periods from 2005-2020 and 5-year birth cohorts from 1920 to 2000. Overall, the younger birth cohort showed lower mortality rates than the older cohort within the same period. In 2020, clusters of high GC mortality were observed in the central area for men (Chungcheongbuk-do, Jeollabuk-do, Gyeongsangbuk-do, and Gyeongsangnam-do) and in the eastern area for women (Gyeongsangbuk-do). Conclusion This study identified a downward trend in GC mortality among men and women from 2000 to 2020 in Korea. This trend was mainly attributed to birth cohort rather than period effects. Spatial analysis showed high GC mortality in the Chungcheong-do and Gyeongsangbuk-do areas. [ABSTRACT FROM AUTHOR]

Purpose Quality assessment of breast cancer treatment in South Korea showed the upward standardization of the grade since 2013, but treatment disparities still have existed. This study analyzed the 5-year trend between 2013 and 2017 in the assessment of breast cancer treatment practice using the Korean health insurance data. Materials and Methods All the medical records including surgery, chemotherapy, and radiotherapy for 7,354 patients a year on average were evaluated. Twenty indices consisted of one structural, 17 process-related, and two result-related factors. We calculated the coefficient of variation (CV) annually to determine the variation in adherence rate of evaluation indices according to the type of institution (advanced vs. general hospital vs. clinic). Results Based on the initial assessment in 2013, 10 out of 20 indicators showed significant variation among the types of institutions with a CV of less than 0.1%. Six of them had a CV decline of less than 0.1%. The CV was still 0.1% or higher in the four indicators, including the composition of professional staff, the implementation of target therapy, the average length of hospital stay, and the hospitalization cost. Regarding the first grade of assessment, there was a statistically significant relationship between the institution type (p=0.029) and region (metropolitan vs. province, p < 0.001). Conclusion There were disparities in the structural and systemic treatment factors depending on the institutional type. The quality improvement of the regional institutions and multidisciplinary experts for breast cancer is necessary. [ABSTRACT FROM AUTHOR]

Purpose This single-arm phase II trial investigate the efficacy and safety of S-1 plus oxaliplatin (SOX) in patients with metastatic breast cancer. Materials and Methods Patients with metastatic breast cancer previously treated with anthracyclines and taxanes were enrolled. Patients received S-1 (40-60 mg depending on patient's body surface area, twice a day, day 1-14) and oxaliplatin (130 mg/m², day 1) in 3 weeks cycle until disease progression or unacceptable toxicity. The primary endpoint was objective response rate (ORR) according to Response Evaluation Criteria in Solid Tumor 1.1. Secondary endpoints included time-to-progression (TTP), duration-of-response (DoR), overall survival (OS), and adverse events. Results A total of 87 patients were enrolled from 11 institutions in Korea. Hormone receptor was positive in 54 (62.1%) patients and six (6.9%) had human epidermal growth factor receptor 2-positive disease. Forty-eight patients (85.1%) had visceral metastasis and 74 (55.2%) had more than three sites of metastases. The ORR of SOX regimen was 38.5% (95% confidence interval [CI], 26.9 to 50.0) with a median TTP of 6.0 months (95% CI, 5.1 to 6.9). Median DoR and OS were 10.3 months (95% CI, 5.5 to 15.1) and 19.4 (95% CI, not estimated) months, respectively. Grade 3 or 4 neutropenia was reported in 28 patients (32.1%) and thrombocytopenia was observed in 23 patients (26.6%). Conclusion This phase II study showed that SOX regimen is a reasonable option in metastatic breast cancer previously treated with anthracyclines and taxanes. [ABSTRACT FROM AUTHOR]

Purpose Assessing the metastasis status of the sentinel lymph nodes (SLNs) for hematoxylin and eosin-stained frozen tissue sections by pathologists is an essential but tedious and time-consuming task that contributes to accurate breast cancer staging. This study aimed to review a challenge competition (HeLP 2019) for the development of automated solutions for classifying the metastasis status of breast cancer patients. Materials and Methods A total of 524 digital slides were obtained from frozen SLN sections: 297 (56.7%) from Asan Medical Center (AMC) and 227 (43.4%) from Seoul National University Bundang Hospital (SNUBH), South Korea. The slides were divided into training, development, and validation sets, where the development set comprised slides from both institutions and training and validation set included slides from only AMC and SNUBH, respectively. The algorithms were assessed for area under the receiver operating characteristic curve (AUC) and measurement of the longest metastatic tumor diameter. The final total scores were calculated as the mean of the two metrics, and the three teams with AUC values greater than 0.500 were selected for review and analysis in this study. Results The top three teams showed AUC values of 0.891, 0.809, and 0.736 and major axis prediction scores of 0.525, 0.459, and 0.387 for the validation set. The major factor that lowered the diagnostic accuracy was micro-metastasis. Conclusion In this challenge competition, accurate deep learning algorithms were developed that can be helpful for making a diagnosis on intraoperative SLN biopsy. The clinical utility of this approach was evaluated by including an external validation set from SNUBH. [ABSTRACT FROM AUTHOR]

Purpose The impact of epidermal growth factor receptor (EGFR) mutation in locally advanced non-small cell lung cancer (NSCLC) remains controversial. This study was conducted to investigate the clinical outcomes and recurrence patterns after definitive chemoradiotherapy (CRT) in patients with unresectable stage III non-squamous-cell lung cancer according to EGFR mutation status. Materials and Methods We retrospectively reviewed 604 patients with pathologically confirmed stage III NSCLC who were treated with definitive CRT and were examined for EGFR mutation at Samsung Medical Center, Korea, from January 2013 to December 2018. Among them, we identified 236 patients with stage III non-squamous-cell lung cancer who were treated with definitive CRT and were examined for EGFR mutation status. We analyzed the frequency of EGFR mutation, progression-free survival (PFS), overall survival (OS), objective response rate (ORR), and recurrence pattern. Results Among 236 patients, EGFR mutation was detected in 71 patients (30.1%) and the median follow-up duration was 41.7 months. There were no significant differences in PFS (9.9 vs. 10.9 months, p=0.236), and ORR to CRT (93.0% vs. 90.3%, p=0.623) according to EGFR mutation status. However, the EGFR mutant group showed significantly higher recurrence (88.7% vs. 75.2%, p=0.022), distant metastasis (76.1% vs. 61.2%, p=0.036) rates, especially brain (38.0% vs. 12.7%, p < 0.001), and better median OS (59.2 vs. 41.3 months, p=0.037) compared with patients without EGFR mutation. Conclusion Patients with EGFR mutation-positive unresectable stage III non-squamous lung cancer exhibited higher recurrence and distant metastasis rates, especially brain metastasis. [ABSTRACT FROM AUTHOR]

Purpose We developed a comprehensive return to work (RTW) intervention covering physical, psycho-social and practical issues for patients newly diagnosed and evaluated its efficacy in terms of RTW. Materials and Methods A multi-center randomized controlled trial was done to evaluate the efficacy of the intervention conducted at two university-based cancer centers in Korea. The intervention program comprised educational material at diagnosis, a face-to-face educational session at completion of active treatment, and three individualized telephone counseling sessions. The control group received other education at enrollment. Results At 1-month post-intervention (T2), the intervention group was more likely to be working compared to the control group after controlling working status at diagnosis (65.4% vs. 55.9%, p=0.037). Among patients who did not work at baseline, the intervention group was 1.99-times more likely to be working at T2. The mean of knowledge score was higher in the intervention group compared to the control group (7.4 vs. 6.8, p=0.029). At the 1-year follow-up, the intervention group was 65% (95% confidence interval, 0.78 to 3.48) more likely to have higher odds for having work. Conclusion The intervention improved work-related knowledge and was effective in facilitating cancer patients' RTW. [ABSTRACT FROM AUTHOR]

Purpose An increasing number of patients with cancers are interested in complementary and alternative medicine (CAM), which lacks scientific evidence. This study aimed to determine how CAM was used and how media affected patients in online cancer support groups (OCSG). Materials and Methods Between August 18 and September 12, 2021, an online survey was conducted among the members of OCSG. The survey consisted of five parts: baseline characteristics, attitudes toward and experience with CAM, source of information and reliabilities, experience with anthelmintics, and online health information literacy and usage. Results Among the 644 responders, a total of 221 patients with cancer completed the survey, and 78.2% (173/221) used CAM. The users' median age was 52 years; 46.8% were males, and 43.9% had metastatic disease. Fifty-three CAM users (30.6%) discussed their physicians about CAM. In addition, 16.2% (28/173) of CAM users had the experience of anthelmintics. The use of anthelmintics in patients with cancers was associated with younger age (odds ratio [OR], 0.89; 95% confidence interval [CI], 0.84 to 0.95), metastatic disease (OR, 10.88; 95% CI, 3.39 to 34.86), previous exposure to CAM information (OR, 5.57; 95% CI, 1.01 to 30.72), experience with more types of CAM (OR, 1.98; 95% CI, 1.29 to 3.05), and side effects (OR, 5.10; 95% CI, 1.46 to 17.75). Conclusion Use of anthelmintics, a CAM of which information is widespread online, is affected by several factors. This study will provide essential information for developing a CAM management strategy in this digital age. [ABSTRACT FROM AUTHOR]

Purpose This study aimed to elucidate the trends and characteristics of the cancer burden in Korea by cancer site, region, and income level. Materials and Methods Korean National Burden of Disease research methodology was applied to measure the cancer burden in Korea from 2008 to 2018. The cause of death and National Health Insurance claims data were obtained from Statistics Korea and the National Health Insurance Service, respectively. An incidence-based approach was applied to calculate the disability-adjusted life-years, which is a summary measure of population health. Results In the past decade, the cancer burden in Korea increased from 2,088 to 2,457 person-years per 100,000 population. Among the cancer burden, the years of life lost decreased, and the years lived with disabilities increased. Cancers of the trachea, bronchus, and lung had the highest disease burden, followed by those of the stomach, colon and rectum, liver, and breast. Conclusion The findings of this study can provide valuable quantitative data for prioritizing and evaluating cancer prevention strategies and implementing cancer policies. Estimating the difference in cancer burden according to region and income level within a country can yield useful data to understand the nature of the cancer burden and scale of the problem. In addition, the results of this study provide a better understanding of the causes of cancer patterns, thereby generating new hypotheses regarding its pathogenesis. [ABSTRACT FROM AUTHOR]

Purpose This study aimed to report the projected cancer incidence and mortality for the year 2023 to estimate Korea's current cancer burden. Materials and Methods Cancer incidence data from 1999 to 2020 were obtained from the Korea National Cancer Incidence Database, and cancer mortality data from 1993 to 2021 were acquired from Statistics Korea. Cancer incidence and mortality were projected by fitting a linear regression model to observed age-specific cancer rates against their respective years and then by multiplying the projected age-specific rates by the anticipated age-specific population for 2023. A joinpoint regression model was used to determine the year in which the linear trend changed significantly; we only used the data of the latest trend. Results In total, 273,076 new cancer cases and 81,818 cancer deaths are expected to occur in Korea in 2023. The most common cancer site is expected to be the lung, followed by the thyroid, breast, colon and rectum, and stomach. These five cancers are expected to represent half of the overall burden of cancer in Korea. The most common type of cancer leading to death is expected to be lung cancer, followed by liver, colorectal, pancreatic, and gallbladder cancers. Conclusion The incidence rates for all types of cancer in Korea are estimated to gradually decrease. These up-to-date estimates of the cancer burden in Korea could be an important resource for planning and evaluating cancer-control programs. [ABSTRACT FROM AUTHOR]

Purpose The current study provides national cancer statistics and their secular trends in Korea, including incidence, mortality, survival, and prevalence in 2020. Materials and Methods Incidence, survival, and prevalence rates of cancer were calculated using the Korea National Cancer Incidence Database, from 1999 to 2020, with survival follow-up until December 31, 2021. Deaths from cancer were assessed using causes-of-death data obtained from Statistics Korea. Results The number of new cancer diagnoses in 2020 decreased by 9,218 cases (3.6%) compared to 2019. In 2020, newly diagnosed cancer cases and deaths from cancer were reported as 247,952 (age-standardized rate [ASR], 262.2 per 100,000) and 82,204 (ASR, 69.9 per 100,000), respectively. The overall cancer incidence rates increased by 3.3% annually from 1999 to 2012, and decreased by 5.0% annually from 2012 to 2015, thereafter, followed by nonsignificant changes. Cancer mortality rates have been decreasing since 2002, with more rapid decline in recent years. The 5-year relative survival between 2016 and 2020 was 71.5%, which contributed to prevalent cases reaching over 2.2 million in 2020. Conclusion In 2020, the number of newly diagnosed cancer patients decreased due to the coronavirus disease 2019 pandemic, but the overall trend is on the rise. Cancer survival rates have improved over the past decades. As the number of cancer survivors increases, a comprehensive cancer control strategy should be implemented in line with the changing aspects of cancer statistics. The long-term impact of the coronavirus disease 2019 pandemic on cancer statistics needs to be investigated in the future. [ABSTRACT FROM AUTHOR]

Purpose Renal tumors account for approximately 7% of all childhood cancers. These include Wilms tumor (WT), clear cell sarcoma of the kidney (CCSK), malignant rhabdoid tumor of the kidney (MRTK), renal cell carcinoma (RCC), congenital mesoblastic nephroma (CMN) and other rare tumors. We investigated the epidemiology of pediatric renal tumors in Korea. Materials and Methods From January 2001 to December 2015, data of pediatric patients (0-18 years) newly-diagnosed with renal tumors at 26 hospitals were retrospectively analyzed. Results Among 439 patients (male, 240), the most common tumor was WT (n=342, 77.9%), followed by RCC (n=36, 8.2%), CCSK (n=24, 5.5%), MRTK (n=16, 3.6%), CMN (n=12, 2.7%), and others (n=9, 2.1%). Median age at diagnosis was 27.1 months (range, 0 to 225.5 months) and median follow-up duration was 88.5 months (range, 0 to 211.6 months). Overall, 32 patients died, of whom 17, 11, 1, and three died of relapse, progressive disease, second malignant neoplasm, and treatment-related mortality. Five-year overall survival and event-free survival were 97.2% and 84.8% in WT, 90.6% and 82.1% in RCC, 81.1% and 63.6% in CCSK, 60.3% and 56.2% in MRTK, and 100% and 91.7% in CMN, respectively (p < 0.001). Conclusion The pediatric renal tumor types in Korea are similar to those previously reported in other countries. WT accounted for a large proportion and survival was excellent. Non-Wilms renal tumors included a variety of tumors and showed inferior outcome, especially MRTK. Further efforts are necessary to optimize the treatment and analyze the genetic characteristics of pediatric renal tumors in Korea. [ABSTRACT FROM AUTHOR]

Purpose Although osimertinib is the standard-of-care treatment of epidermal growth factor receptor (EGFR) T790M mutation–positive non–small cell lung cancer, real-world evidence on the efficacy of osimertinib is not enough to reflect the complexity of the entire course of treatment. Herein, we report on the use of osimertinib in patients with EGFR T790M mutation–positive non–small cell lung cancer who had previously received EGFR tyrosine kinase inhibitor (TKI) treatment in Korea. Materials and Methods Patients with confirmed EGFR T790M after disease progression of prior EGFR-TKI were enrolled and administered osimertinib 80 mg daily. The primary effectiveness outcome was progression-free survival, with time-to-treatment discontinuation, treatment and adverse effects leading to treatment discontinuation, and overall survival being the secondary endpoints. Results A total of 558 individuals were enrolled, and 55.2% had investigator-assessed responses. The median progression-free survival was 14.2 months (95% confidence interval [CI], 13.0 to 16.4), and the median time-to-treatment discontinuation was 15.0 months (95% CI, 14.1 to 15.9). The median overall survival was 36.7 months (95% CI, 30.9 to not reached). The benefit with osimertinib was consistent regardless of the age, sex, smoking history, and primary EGFR mutation subtype. However, hepatic metastases at the time of diagnosis, the presence of plasma EGFR T790M, and the shorter duration of prior EGFR-TKI treatment were poor predictors of osimertinib treatment. Ten patients (1.8%), including three with pneumonitis, had to discontinue osimertinib due to severe adverse effects. Conclusion Osimertinib demonstrated its clinical effectiveness and survival benefit for EGFR T790M mutation–positive in Korean patients with no new safety signals. [ABSTRACT FROM AUTHOR]

Purpose This study aimed to provide the clinical characteristics, prognostic factors, and 5-year relative survival rates of lung cancer diagnosed in 2015. Materials and Methods The demographic risk factors of lung cancer were calculated using the KALC-R (Korean Association of Lung Cancer Registry) cohort in 2015, with survival follow-up until December 31, 2020. The 5-year relative survival rates were estimated using Ederer II methods, and the general population data used the death rate adjusted for sex and age published by the Korea Statistical Information Service from 2015 to 2020. Results We enrolled 2,657 patients with lung cancer who were diagnosed in South Korea in 2015. Of all patients, 2,098 (79.0%) were diagnosed with non–small cell lung cancer (NSCLC) and 345 (13.0%) were diagnosed with small cell lung cancer (SCLC), respectively. Old age, poor performance status, and advanced clinical stage were independent risk factors for both NSCLC and SCLC. In addition, the 5-year relative survival rate declined with advanced stage in both NSCLC (82%, 59%, 16%, 10% as the stage progressed) and SCLC (16%, 4% as the stage progressed). In patients with stage IV adenocarcinoma, the 5-year relative survival rate was higher in the presence of epidermal growth factor receptor (EGFR) mutation (19% vs. 11%) or anaplastic lymphoma kinase (ALK) translocation (38% vs. 11%). Conclusion In this Korean nationwide survey, the 5-year relative survival rates of NSCLC were 82% at stage I, 59% at stage II, 16% at stage III, and 10% at stage IV, and the 5-year relative survival rates of SCLC were 16% in cases with limited disease, and 4% in cases with extensive disease. [ABSTRACT FROM AUTHOR]

Purpose The treatment of male breast cancer (MBC) has been extrapolated from female breast cancer (FBC) because of its rarity despite their different clinicopathologic characteristics. We aimed to investigate the distribution of intrinsic subtypes based on immunohistochemistry, their clinical impact, and treatment pattern in clinical practice through a multicenter study in Korea. Materials and Methods We retrospectively analyzed clinical data of 248 MBC patients from 18 institutions across the country from January 1995 to July 2016. Results The median age of MBC patients was 63 years (range, 25 to 102 years). Among 148 intrinsic subtype classified patients, 61 (41.2%), 44 (29.7%), 29 (19.5%), and 14 (9.5%) were luminal A, luminal B, human epidermal growth factor receptor 2, and triple-negative breast cancer, respectively. Luminal A subtype showed trends for superior survival compared to other subtypes. Most hormone receptor-positive patients (166 patients, 82.6%) received adjuvant endocrine treatment. Five-year completion of adjuvant endocrine treatment was associated with superior disease-free survival (DFS) in patients classified with an intrinsic subtype (hazard ratio [HR], 0.15; 95% confidence interval [CI], 0.04 to 0.49; p=0.002) and in all patients (HR, 0.16; 95% CI, 0.05 to 0.54; p=0.003). Conclusion Distribution of subtypes of MBC was similar to FBC and luminal type A was most common. Overall survival tended to be improved for luminal A subtype, although there was no statistical significance. Completion of adjuvant endocrine treatment was associated with prolonged DFS in intrinsic subtype classified patients. MBC patients tended to receive less treatment. MBC patients should receive standard treatment according to guidelines as FBC patients. [ABSTRACT FROM AUTHOR]

Purpose This study aimed to estimate the risk of cancer incidence and mortality according to adherence to lifestyle-related cancer prevention guidelines. Materials and Methods Men and women who participated in the general health screening program in 2002 and 2003 provided by the National Health Insurance Service were included (n=8,325,492). Self-reported smoking, alcohol consumption, and physical activity habits and directly measured body mass index were collected. The participants were followed up until the date of cancer onset or death or 31 December 2018. The Cox proportional hazard model was used to evaluate the hazard ratio (HR) for cancer incidence and mortality according to different combinations of lifestyle behaviors. Results Only 6% of men and 15% of women engaged in healthy behavior at baseline, such as not smoking, not drinking alcohol, being moderately or highly physically active, and within a normal body mass index range. Compared to the best combination of healthy lifestyle behaviors, the weak and moderate associations with increased all cancer incidence (HR < 1.7) and mortality (HR < 2.5) were observed in those with heavy alcohol consumption and in former or current smokers. HRs of cancer mortality were significantly increased among current smokers in most combinations. Conclusion Compared to full adherence to cancer prevention recommendations, unhealthy behaviors increase cancer risk. As few people meet these recommendations, there is a great opportunity for cancer prevention. [ABSTRACT FROM AUTHOR]

Purpose This multicenter retrospective study aimed to investigate clinical, radiologic, and treatment-related factors affecting survival in patients with newly diagnosed diffuse intrinsic pontine glioma (DIPG) treated with radiotherapy. Materials and Methods Patients aged < 30 years who underwent radiotherapy as an initial treatment for DIPG between 2000 and 2018 were included; patients who did not undergo magnetic resonance imaging at diagnosis and those with pathologically diagnosed grade I glioma were excluded. We examined medical records of 162 patients collected from 10 participating centers in Korea. The patients’ clinical, radiological, molecular, and histopathologic characteristics, and treatment responses were evaluated to identify the prognosticators for DIPG and estimate survival outcomes. Results The median follow-up period was 10.8 months (interquartile range, 7.5 to 18.1). The 1- and 2-year overall survival (OS) rates were 53.5% and 19.0%, respectively, with a median OS of 13.1 months. Long-term survival rate (≥ 2 years) was 16.7%, and median OS was 43.6 months. Age (< 10 years), poor performance status, treatment before 2010, and post-radiotherapy necrosis were independently associated with poor OS in multivariate analysis. In patients with increased post-radiotherapy necrosis, the median OS estimates were 13.3 months and 11.4 months with and without bevacizumab, respectively (p=0.138). Conclusion Therapeutic strategy for DIPG has remained unchanged over time, and the associated prognosis remains poor. Our findings suggest that appropriate efforts are needed to reduce the occurrence of post-radiotherapy necrosis. Further well-designed clinical trials are recommended to improve the poor prognosis observed in DIPG patients. [ABSTRACT FROM AUTHOR]

Purpose To provide a wider choice of treatment opportunities for patients with neuroendocrine tumor (NET) in Korea, we have conducted a phase 1, open-label, single-arm, dose-escalation study of SNU-KB-01, a no-carrier added (NCA) 177Lu-labeled DOTATATE. Materials and Methods Seven patients with inoperable, progressive, metastatic, or locally advanced, somatostatin receptor-positive NET with Ki67 index ≤ 20% were enrolled according to the rolling six design. The study consisted of two cohorts to receive 4 cycles of SNU-KB-01 every 8 weeks for the first dose of 5.55 GBq (n=3) and 7.40 GBq (n=4). We assessed the incidence of dose-limiting toxicity (DLT) and adverse event, absorbed dose of kidneys and bone marrow, and objective tumor response. Results Seven patients completed 4 cycles (21.3-30.1 GBq total dose) of SNU-KB-01. The mean absorbed doses to kidneys and bone marrow were 0.500 mGy/MBq and 0.053 mGy/MBq, respectively, and the total body effective dose was 0.115 mSv/MBq. No DLT was observed and the maximum tolerated dose was 7.40 GBq/cycle. Grade 3 thrombocytopenia occurred in one patient, but no other grade 3 or 4 major hematologic or renal toxicity was observed. The best objective response to SNU-KB-01 was partial response. Overall response rate was 42.9% and disease control rate was 85.7%. Conclusion Treatment with 4 cycles of SNU-KB-01 was well tolerated and resulted in control of disease in most of the patients. Our results indicate SNU-KB-01, an NCA 177Lu-labeled DOTATATE, as a potentially safe and efficacious treatment option for NET patients in Korea. [ABSTRACT FROM AUTHOR]

Purpose As the survival of head and neck cancer (HNC) improves, survivors increasingly confront non-cancer–related deaths. This nationwide population-based study aimed to investigate non-cancer–related deaths in HNC survivors. Materials and Methods Data from the Korean Central Cancer Registry were obtained to characterize causes of death, mortality patterns, and survival in patients with HNC between 2006 and 2016 (n=40,890). Non-cancer-related mortality relative to the general population was evaluated using standardized mortality ratios (SMRs). The 5- and 10-year cause-specific competing risks probabilities of death (cumulative incidence function, CIF) and subdistribution hazards ratios (sHR) from the Fine-Gray models were estimated. Results Comorbidity-related mortality was frequent in older patients, whereas suicide was predominant in younger patients. The risk of suicide was greater in patients with HNC than in the general population (SMR, 3.1; 95% confidence interval [CI], 2.7 to 3.5). The probability of HNC deaths reached a plateau at 5 years (5-year CIF, 33.9%; 10-year CIF, 39.5%), whereas the probability of non-HNC deaths showed a long-term linear increase (5-year, CIF 5.6%; 10-year CIF, 11.9%). Patients who were male (sHR, 1.56; 95% CI, 1.41 to 1.72), diagnosed with early-stage HNC (localized vs. distant: sHR, 1.86; 95% CI, 1.58 to 2.21) and older age (65-74 vs. 0-44: sHR, 6.20; 95% CI, 4.92 to 7.82; ≥ 75 vs. 0-44: sHR, 9.81; 95% CI, 7.76 to 12.39) had an increased risk of non-cancer mortality. Conclusion Non-HNC–related deaths continue increasing. HNC survivors are at increased risk of suicide in the younger and comorbidity-related death in the older. Better population-specific surveillance awareness and survivorship plans for HNC survivors are warranted. [ABSTRACT FROM AUTHOR]

Purpose We aimed to investigate manifestations and patterns of care for patients with brain metastasis (BM) from breast cancer (BC) and compared their overall survival (OS) from 2005 through 2014 in Korea. Materials and Methods We retrospectively reviewed 600 BC patients with BM diagnosed between 2005 and 2014. The median follow-up duration was 12.5 months. We categorized the patients into three groups according to the year when BM was initially diagnosed (group I [2005-2008], 98 patients; group II [2009-2011], 200 patients; and group III [2012-2014], 302 patients). Results Over time, the median age at BM diagnosis increased by 2.2 years (group I, 49.0 years; group II, 48.3 years; and group III, 51.2 years; p=0.008). The percentage of patients with extracranial metastasis was 73.5%, 83.5%, and 86.4% for group I, II, and III, respectively (p=0.011). The time interval between BC and BM was prolonged in patients with stage III primary BC (median, 2.4 to 3 years; p=0.029). As an initial brain-directed treatment, whole-brain radiotherapy alone decreased from 80.0% in 2005 to 41.1% in 2014. Meanwhile, stereotactic radiosurgery or fractionated stereotactic radiotherapy alone increased from 13.3% to 34.7% during the same period (p=0.005). The median OS for group I, II, and III was 15.6, 17.9, and 15.0 months, respectively, with no statistical significance. Conclusion The manifestations of BM from BC and the pattern of care have changed from 2005 to 2014 in Korea. However, the OS has remained relatively unchanged over the 10 years. [ABSTRACT FROM AUTHOR]

Purpose Melanoma incidence is rising worldwide along with the associated personal and socioeconomic health expenditures. We investigated the incidence and survival-rate patterns of melanoma in South Korea using nationwide data. Materials and Methods This retrospective cohort study included patients with melanoma between 2004 and 2017, based on National Health Insurance (NHI) claims data in South Korea. The incidence, prevalence, and survival rate were analyzed along with baseline demographic characteristics. We collected solar irradiation dose and healthcare ranking score (HRS) according to the administrative district from the Korea Meteorological Administration and Korea Health Promotion Institute. The incidence and survival rates were assessed using Pearson’s correlation, the Kaplan-Meier estimation, multiple linear regression, and multiple logistic regression methods. Results Twenty-five thousand, five hundred ninety-one patients with melanoma were diagnosed during the study period. The agestandardized incidence of melanoma steadily increased from 2004 to 2017 from 2.6 to 3.0/100,000/yr. The incidence of melanoma increased with significantly higher income (p < 0.05). The prevalence followed a similar pattern as the incidence. According to multivariate analysis, HRS significantly influenced the incidence of melanoma in high sun-exposed sites (p < 0.001). There was no significant change in annual mortality. Women had a higher 5-year survival rate than men (78.4% vs. 72.8%). Mortality by the administrative district was highly correlated with HRS. Conclusion The incidence of melanoma is increasing in South Korea. A low HRS is associated with both higher incidence and mortality. The findings of this study could be utilized as a guideline for treating melanoma patients. [ABSTRACT FROM AUTHOR]

Although palliative sedation (PS) is a common practice in the palliative care of cancer patients in Western countries, there is little related research on the practice in Korea. PS can be classified into several categories according to sedation level and continuity. PS is clearly distinct from euthanasia. While euthanasia is illegal and regarded as unethical in Korea, there is little ethical and legal controversy about PS in terms of the doctrine of double effect. Most studies have asserted that PS does not shorten the survival of terminal cancer patients. Since preference for PS heavily depends on stakeholder value, it should be preceded by shared decision-making through full communication among the patient, family members, and medical team. This is a narrative review article analyzing previous studies, especially from the three Eastern Asian countries, Korea, Japan and Taiwan, which share similar cultures compared with Western countries. Practical issues concerning PS—for example, prevalence, type and dosage of medications, salvage medication, timing of its initiation, and assessment—are described in detail. [ABSTRACT FROM AUTHOR]

Purpose While renal impairment is one of the first clinical manifestations of multiple myeloma (MM), declined renal function may conversely be a risk factor for cancers including MM. In this study, we investigated the relationship between chronic kidney disease and MM at a population level. Materials and Methods A total of 9,809,376 adults who participated in a nationwide health screening program and had no MM, cancer or end-stage renal disease at baseline were investigated for incidence of MM. The impact of estimated glomerular filtration rate (eGFR) and random urine dipstick proteinuria, and interactive associations of the two factors on the MM incidence were evaluated. Results The general incidence of MM was 4.8 per 100,000 person-years (mean follow-up of 8.3 years). Participants with eGFR < 60 mL/min/1.73 m2 (5.8% of participants) had higher MM incidence than those with eGFR ≥ 60 mL/min/1.73 m2 (adjusted hazard ratio, 1.29; 95% confidence interval, 1.17 to 1.43). When eGFR was graded into five levels, there was a significant inverse doseresponse relationship between eGFR level and MM incidence at the lower eGFR levels (reference: eGFR 60-89 mL/min/1.73 m2). A dose-response relationship was also found with degree of dipstick proteinuria and incidence of MM. Conclusion Adults with decreased renal function indicated either by decreased eGFR or presence of proteinuria are at a higher risk of developing MM compared to those without, and there is a dose-response relationship between the severity of renal impairment and MM incidence. [ABSTRACT FROM AUTHOR]

Purpose Poor oral health is associated with head and neck cancer (HNC). We evaluated whether a national oral health screening program (OHSP) could reduce the risk of HNC. Materials and Methods Data from 408,247 healthy individuals aged ≥ 40 years from the National Health Insurance System-National Health Screening program during 2003 and 2004 in Korea were analyzed. The risk of HNC was compared between subjects who underwent OHSP (HEALS-Dental+, n=165,292) and routine health check-ups only (HEALS-Dental–, n=242,955). The impact of individual oral health-related factors on HNC risk was evaluated in HEALS-Dental+. Results A total of 1,650 HNC cases were diagnosed. The 10-year HNC-free rate was 99.684% with a median follow-up of 11 years. The risk of all HNC (hazard ratio [HR], 1.16; 95% confidence interval [CI], 1.03 to 1.29; p=0.011) and oropharyngeal cancer (HR, 1.48; 95% CI, 1.13 to 1.94; p=0.005) was significantly higher in HEALS-Dental– than in HEALS-Dental+. In HEALS-Dental+, oral cavity cancer was marginally reduced (p=0.085), and missing teeth was a significant factor for HNC (HR, 1.24; 95% CI, 1.02 to 1.50; p=0.032). Toothbrushing was a significant factor in univariate analysis (p=0.028), but not in multivariate analysis (p=0.877). Conclusion The National OHSP significantly reduced the long-term HNC risk, particularly the incidence of oropharyngeal cancer. Routine OHSP should be considered at the population level. [ABSTRACT FROM AUTHOR]

Purpose The current study aimed to identify the overall characteristics of cancer-related emergency department (ED) visits by adult in Korea, including analyses of factors associated with ED stay time and outcomes nationwide. Materials and Methods We collected data on cancer-related ED visits from the National Emergency Department Information System (NEDIS) database between 2017 and 2019. Results ED visits by cancer patients comprised 5.5% (667,935 visits) of total ED visits from 2017 to 2019, which was slightly higher than in other counties. Patients with cancer who visited the ED were over 50 years old, the majority being males, and patients with cancer visited EDs in certified tertiary hospitals more frequently than patients without cancer. In multivariate analyses, the adjusted odds ratio for a length of stay more than 8 hours in the ED of certified tertiary hospitals was 126.34 (95% confidence interval, 1.422 to 1.460) when compared to hospitals. Nevertheless, the longer the patients stayed in the ED, the more likely they were to be admitted. Conclusion The longer ED stay and higher proportion of cancer patient hospitalizations suggest that cancer patients visit ED to be admitted as well as to receive acute care. The frequency of ED visits and admission may be adjusted to some extent depending on outpatient education, such as self-management of symptoms and situations. Improving cancer care in local communities should be met though provisions such as linking treatment between hospitals or supplying appropriate medical personnel, even for the efficient use of ED resources in hospitals. [ABSTRACT FROM AUTHOR]

Purpose Literature is scarce regarding cancer care utilization during the massive outbreak of coronavirus disease 2019 (COVID-19) in the Republic of Korea. We investigated functional impairments in mental health and their relationships with depression, anxiety regarding the viral epidemic, and disruptions in healthcare service utilization among cancer patients in the COVID-19 pandemic era. Materials and Methods We used an online survey with questions related to the disturbances faced by patients with cancer in utilizing healthcare services in the pandemic era. Current mental health status was assessed using the Work and Social Adjustment Scale (WSAS), Stress and Anxiety to Viral Epidemics-6 (SAVE-6) scale, Patient Health Questionnaire-9 (PHQ-9), Insomnia Severity Index (ISI), Brief Resilience Scale (BRS), Cancer-Related Dysfunctional Beliefs about Sleep Scale (C-DBS), and Fear of COVID-19 over Cancer (FCC). Results Among the 221 responders, 95 (43.0%) reported disruptions in healthcare service utilization during the COVID-19 pandemic. Logistic regression analysis revealed that functional impairment in the mental health of these patients was expected due to disruptions in healthcare service utilization, high levels of depression, anxiety regarding the viral epidemic, fear of COVID over cancer, and low resilience. Mediation analysis showed that patient resilience and cancer-related dysfunctional beliefs about sleep partially mediated the effects of viral anxiety on functional impairment. Conclusion In this pandemic era, patients with cancer experience depression, anxiety regarding the viral epidemic, and disruptions in healthcare service utilization, which may influence their functional impairments in mental health. [ABSTRACT FROM AUTHOR]

Purpose We aimed to develop a prognostic model to assist palliative care referral at least 3 months before death in advanced cancer patients treated at an outpatient medical oncology clinic. Materials and Methods In this prospective cohort study, a total of 200 patients were enrolled at a tertiary cancer center in South Korea. The major eligibility criterion was an expected survival of less than a year as estimated by their oncologists. We analyzed the influences of known prognostic factors along with chemotherapy status, mid-arm circumference, and triceps skinfold thickness on survival time. Results The mean age of the patients was 64.5 years, 36% were female, and the median survival time was 7.6 months. In the multivariate analysis, we found six significant factors related to poor survival: a poor Eastern Cooperative Oncology Group (ECOG) performance status (≥ 2), not undergoing chemotherapy, anorexia, a low lymphocyte level (< 12%), a high lactate dehydrogenase (LDH) level (≥ 300 IU/L), and a low mid-arm circumference (< 23 cm). We developed a prognostic model (score, 0-8.0) to predict 3-month survival based on the multivariate analysis. Patients who scored ≥ 4.0 points had a short survival of less than 3 months (p < 0.001). The discriminating ability of the prognostic model using the area under the receiver operating characteristic curve was 0.88. Conclusion The prognostic model using ECOG performance status, chemotherapy status, anorexia, lymphocytes, LDH, and mid-arm circumference can predict 3-month survival in medical oncology outpatients. It can alert oncologists to refer patients to palliative care specialists before it is too late. [ABSTRACT FROM AUTHOR]

Purpose Due to low incidence, epidemiologic data of Ewing sarcoma in the Asian population are scarce. We aimed to examine the incidence pattern and outcome of patients with Ewing sarcoma in the Republic of Korea. Materials and Methods Data of patients with Ewing sarcoma diagnosed between 1999 and 2017 were obtained from the Korea Central Cancer Registry (KCCR). Incidence, clinical characteristics, and survival rates were analyzed and compared between different age groups. Results There were 788 cases (459 males, 329 females), with a median age at diagnosis of 20 years. The age-standardized rate of Ewing sarcoma was 1.01. The number of cases and incidence rates in each age group were as follows: children, 1.6; adolescents and young adults (AYA), 0.93; adults, 0.44; and elderly, 0.53. There were more male cases in children and the AYA group (p < 0.001). Extraskeletal tumors (p < 0.001), primary sites other than extremity (p=0.007), and presence of metastasis at diagnosis (p=0.031) were more frequent in the adults and elderly group. With a median survival time of 78 months, the 5-year overall survival (OS) rate of the entire cohort was 52%. Children fared best (5-year OS, 75%), and the 5-year OS of AYA patients (51%) approximated the OS of the entire cohort. A two-fold difference of 5-year OS was observed between adults and elderly patients (42% vs. 19%). On univariate and multivariate analyses, age ≥ 15 years and presence of metastasis were adverse prognostic factors. Conclusion This was the first epidemiologic study of Ewing sarcoma using the KCCR data. With a similar incidence to other Asian countries, the survival rate was slightly lower than that of Euro-American cases. Collaborative clinical studies are necessary to improve the outcome of Ewing sarcoma in low-incidence populations. [ABSTRACT FROM AUTHOR]

Purpose Children with Down syndrome (DS) show a higher risk of acute leukemia than those without DS. In this study, we investigated the nationwide incidence of acute leukemia among children with DS and compared their epidemiologic characteristics with those of children with acute leukemia but without DS. Materials and Methods Using the National Health Insurance Service database, we selected patients with acute leukemia aged 0-19 years at diagnosis between 2007 and 2016. Results Among the 4,697 children with acute leukemia, 54 (1.1%) had DS. The median incidence rate of leukemia with DS by year was 1.3% (range, 0.2% to 2.0%). Sixteen patients with acute lymphoblastic leukemia (ALL; 29.6%) and 36 with acute myeloid leukemia (AML; 66.7%) had DS. The DS group showed younger age at diagnosis than the non-DS group, and diagnosis of AML was more frequent in the DS group than in the non-DS group (3 years vs. 9 years, p < 0.001; 66.7% vs. 32.4%, p < 0.001, respectively). The 5-year overall survival was comparable between the DS and non-DS groups (88.0% vs. 81.9%, p=0.375). Among all the Koreans born between 2007 and 2008, the incidences of acute leukemia, ALL, and AML were 49.25, 20.75, and 163.38 times higher, respectively, in the DS group than in the non-DS group. Conclusion Our findings support the fact that the incidence of acute leukemia is higher among patients with DS than among those without DS in Korea. However, the DS and non-DS groups in this study had a comparable overall survival rate. [ABSTRACT FROM AUTHOR]

Purpose We aimed to assess the real-world efficacy of nab-paclitaxel in metastatic breast cancer patients. Materials and Methods This is a retrospective study performed in two tertiary referral hospitals in Korea. Patients with metastatic breast cancer treated with nab-paclitaxel (Abraxane) between March 2016 and March 2020 were enrolled. Results A total of 102 patients with metastatic breast cancer were included. Patients were heavily pre-treated with a median of four prior lines of chemotherapy (5 lines when including endocrine therapy in hormone-receptor-positive patients), and 66 patients (64.7%) were exposed to taxanes in the metastatic setting. According to St. Gallen molecular subtypes, 36 patients (35.3%) were luminal A, 28 (27.5%) were luminal B, 18 (17.7%) were human epidermal growth factor receptor 2-positive and 20 (19.6%) had triplenegative disease. Fifty patients (49.0%) were treated with a 3-weekly regimen (260 mg/m² on day 1 every 3 weeks), and 52 (51.0%) were treated with a weekly regimen (100 mg/m² every week). Objective response rate was 22.9%. After a median follow-up of 22.0 months, median progression-free survival (PFS) was 4.0 months (95% confidence interval [CI], 2.6 to 4.8) and median overall survival was 8.7 months (95% CI, 7.5 to 11.2). Patients treated with weekly regimen had longer PFS compared to 3-weekly regimen (5.5 vs. 2.3 months, p < 0.001). Multivariate analysis revealed the treatment regimen as an independent prognostic factor for PFS. There was no grade 3 or 4 hypersensitivity reaction. Conclusion This real-world data shows that nab-paclitaxel is a reasonable treatment option in heavily pre-treated and/or taxaneexposed metastatic breast cancer patients. [ABSTRACT FROM AUTHOR]

Purpose The KNOG-1101 study showed improved 2-year progression-free survival (PFS) with temozolomide during and after radiotherapy compared to radiotherapy alone for patients with anaplastic gliomas. This trial investigates the effect of concurrent and adjuvant temozolomide on health-related quality of life (HRQoL). Materials and Methods In this randomized, open-label, phase II trial, 90 patients with World Health Organization grade III glioma were enrolled across multiple centers in South Korea between March 2012 to February 2015 and followed up through 2017. The European Organization for Research and Treatment of Cancer Quality of Life Questionnaire 30 (EORTC QLQ-C30) and 20-item EORTC QLQ-Brain Neoplasm (QLQ-BN20) were used to compare HRQoL between patients assigned to concurrent chemoradiotherapy with temozolomide followed by 6 cycles of adjuvant temozolomide (arm A) and radiotherapy (RT) alone (arm B). Results Of the 90 patients in the study, 84 patients (93.3%) completed the baseline HRQoL questionnaire. Emotional functioning, fatigue, nausea and vomiting, dyspnea, constipation, appetite loss, diarrhea, seizures, itchy skin, drowsiness, hair loss, and bladder control were not affected by the addition of temozolomide. All other items did not differ significantly between arm A and arm B throughout treatment. Global health status particularly stayed consistent at the end of adjuvant temozolomide (p=0.47) and at the end of RT (p=0.33). Conclusion The addition of concurrent and adjuvant temozolomide did not show negative influence on HRQoL with improvement of PFS for patients with anaplastic gliomas. The absence of systematic and clinically relevant changes in HRQoL suggests that an overall long-term net clinical benefit exists for concurrent and adjuvant temozolomide. [ABSTRACT FROM AUTHOR]

Purpose This study investigated the attitudes toward risk-reducing mastectomy (RRM) and risk-reducing salpingo-oophorectomy (RRSO) as cancer prevention options for BRCA1/2 carriers in healthy, young, unmarried Korean women. Materials and Methods A nationally representative sample of 600 women, aged 20-39 years, completed a questionnaire on sociodemographic variables, preference for genetic testing, and intention to undergo risk-reducing surgeries after receiving information on the cancer risk of BRCA1/2 mutations and benefits of risk-reducing surgeries. Results A total of 54.7% and 57.7% had the intention to undergo RRM and RRSO, respectively, on the assumption that they were BRCA1/2 carriers. Older age and no intention to undergo genetic testing were associated with a reduced likelihood of undergoing RRM (odds ratio [OR], 0.30; 95% confidence interval [CI], 0.14 to 0.61 for age 35-39 years and OR, 0.35; 95% CI, 0.20 to 0.62 for no intention for genetic testing) and RRSO (OR, 0.39; 95% CI, 0.19 to 0.79 for age 35-39 years and OR, 0.30; 95% CI, 0.17 to 0.53 for no intention for genetic testing). Women who chose to be single were likely to undergo risk-reducing surgeries (OR, 1.67; 95% CI, 1.07 to 2.60 for RRM and OR, 1.56; 95% CI, 1.00 to 2.44 for RRSO). Conclusion More than 50% of healthy, unmarried, young Korean women were inclined to undergo prophylactic surgeries if they were BRCA1/2 mutation carriers. Further studies on decision-making process for cancer prevention in individuals at high risk for cancer need to be conducted. [ABSTRACT FROM AUTHOR]

Purpose This study aimed to assess the feasibility of operational definitions of cancer patients in conducting cancer-related studies using the claims data from the National Health Insurance Service (NHIS). Materials and Methods Cancer incidence data were obtained from the Korean Central Cancer Registry, the NHIS primary diagnosis, and from the rare and intractable disease (RID) registration program. Results The operational definition with higher sensitivity for cancer patient verification was different by cancer type. Using primary diagnosis, the lowest sensitivity was found in colorectal cancer (91.5%; 95% confidence interval [CI], 91.7 to 92.0) and the highest sensitivity was found in breast cancer (97.9%; 95% CI, 97.8 to 98.0). With RID, sensitivity was the lowest in liver cancer (91.9%; 95% CI, 91.7 to 92.0) and highest in breast cancer (98.1%; 95% CI, 98.0 to 98.2). In terms of the difference in the date of diagnosis in the cancer registration data, > 80% of the patients showed a < 31-day difference from the RID definition. Conclusion Based on the NHIS data, the operational definition of cancer incidence is more accurate when using the RID registration program claims compared to using the primary diagnosis despite the relatively lower concordance by cancer type requires additional definitions such as treatment. [ABSTRACT FROM AUTHOR]