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Abstract Background We aimed to comprehensively investigate the optimal cumulative cisplatin dose during concurrent chemoradiotherapy (CC-CCD) for locoregionally advanced nasopharyngeal carcinoma (CA-LANPC) with different tumor responses after neoadjuvant chemotherapy (NAC). Methods Patients with CA-LANPC who underwent NAC followed by cisplatin-based concurrent chemoradiotherapy were retrospectively analyzed. Evaluation of tumor response in patients was conducted by Response Evaluation Criteria for Solid Tumor (RECIST) 1.1 after two to four cycles NAC. Multivariate Cox proportional hazards models were used for prognosis. Recursive partitioning analysis (RPA) was conducted to classify participates and predict disease-free survival (DFS). Results One hundred and thirty-two patients with favorable response after NAC were included. The median CC-CCD was 163 mg/m2 (IQR, 145–194 mg/m2), and 160 mg/m2 was selected as the cutoff point to group patients into low and high CC-CCD groups (

ObjectivesThe purpose of this study was to establish a nomogram for predicting cervical lymph node metastasis (CLNM) in patients with papillary thyroid carcinoma (PTC).Materials and MethodsA total of 418 patients with papillary thyroid carcinoma undergoing total thyroidectomy with cervical lymph node dissection were enrolled in the retrospective study from January 2016 to September 2019. Univariate and multivariate Logistic regression analysis were performed to screen the clinicopathologic, laboratory and ultrasound (US) parameters influencing cervical lymph nodes metastasis and develop the predicting model.ResultsCLNM was proved in 34.4% (144/418) of patients. In the multivariate regression analysis, Male, Age < 45 years, Tumor size > 20mm, multifocality, ambiguous boundary, extracapsular invasion and US-suggested lymph nodes metastasis were independent risk factors of CLNM (p < 0.05). Prediction nomogram showed an excellent discriminative ability, with a C-index of 0.940 (95% confidence interval [CI], 0.888-0.991), and a good calibration.ConclusionThe established nomogram showed a good prediction of CLNM in patients with PTC. It is conveniently used and should be considered in the determination of surgical procedures.

Abstract Background Findings remain unclear whether neutrophil-to-lymphocyte ratio (NLR) detrimentally affects advanced nasopharyngeal carcinoma (NPC) prognosis. We aim to evaluate the prognostic value of NLR in patients with NPC based on a large-scale cohort from an endemic area. Methods We selected patients retrospectively from a cohort examining long-term cancer outcomes following diagnosis. Neutrophil counts and lymphocyte counts were assessed prior to treatment. Kaplan–Meier method and log-rank test were used to calculate and compare survival outcomes. Additionally, Cox proportional hazards model was utilized to carry out univariate and multivariate analyses. Results Between October 2009 and August 2012, we enrolled 1550 consecutive NPC patients staged II-IVB. The median value of NLR was 2.27 (interquartile range [IQR], 1.71–3.12). Determined by operating characteristic curve using overall survival (OS) as an endpoint, the cutoff value for NLR was 2.50. At 5 years, NLR > 2.50 was associated with inferior OS (90.3% vs 82.5%; P

Purpose: The benefits of additional use of nimotuzumab (NTZ) in the treatment of locoregionally advanced nasopharyngeal carcinoma (LA-NPC) is largely unclear. We aim to compare LA-NPC treatment outcomes in patients that received CCRT with nimotuzumab (NTZ) to patients that received CCRT only.Materials and Methods: Between October 2009 and January 2012, 31 previously untreated and newly diagnosed LA-NPC patients were administered CCRT (3 cycles of 100 mg/m2 cisplatin every third week with intensity-modulated radiotherapy) plus NTZ according to an IRB-approved institutional research protocol. A well-balanced cohort of 62 patients who received CCRT alone was created by matching each patient who received CCRT plus NTZ via propensity-matched analysis in a 2:1 ratio.Results: Compared with CCRT only, CCRT plus NTZ was significantly associated with superior overall survival (5-year OS; 96.8% vs. 82.3%; P = 0.001), superior distant metastasis-free survival (5-year DMFS; 90.3% vs. 80.6%, P = 0.012) and superior progression-free survival (5-year PFS; 83.9% vs. 71.0%, P = 0.006). In multivariate analysis, the inclusion of NTZ to CCRT was confirmed to be a favorable factor for OS (HR, 0.31; 95% CI, 0.02–0.71; P = 0.027), DMFS (HR, 0.45; 95% CI, 0.13–0.77; P = 0.034), and PFS (HR, 0.38; 95% CI, 0.11–0.89; P = 0.041). In addition, no significant differences in hematology parameters, dermatitis, nausea, vomiting, xerostomia, nephrotoxicity or neurotoxicity were found between the two arms (all P > 0.05).Conclusion: The inclusion of NTZ to CCRT is more effective for long-term survival among LA-NPC patients than CCRT only.

Background/Aims: Lipoproteins have been reported to be associated with prognosis in various cancers; however, the prognostic value of lipoproteins in patients with nasopharyngeal carcinoma (NPC) remains largely unknown. We aim to asses the role of circulating lipoproteins in locoregionally advanced NPC patients. Methods: Between October 2009 and August 2012, a total of 1,081 patients with stage III-IVB NPC were included in the analysis. Circulating high-density lipoprotein (HDL) and low-density lipoprotein (LDL) are the two key lipoproteins, which were measured at baseline. Receiver operating characteristic (ROC) curve analysis was used to evaluate different cut-off points for lipoproteins. Actuarial rates were performed using Kaplan–Meier methods and the log-rank test. Results: The cutoff points of HDL, LDL, and LDL/HDL ratio were 1.17 mmol/L, 3.75 mmol/L, and 2.73, respectively. At 5 years, high HDL (> 1.17 mmol/L) was significantly associated with better overall survival (OS, 86.6% vs. 78.9%; P=0.004), distant metastasis-free survival (DMFS, 86.9% vs. 80.8%; P=0.004), locoregional relapse-free survival (LRFS, 90.8% vs. 85.4%; P=0.010), and progression-free survival (PFS, 79.1% vs. 70.2%; P= 0.001) than low HDL (≤1.17 mmol/L). In contrast, high LDL (> 3.75 mmol/L) tend to be inferior OS (79.1% vs. 84.9%; P= 0.016) in compassion with low LDL (≤3.75 mmol/L). Likewise, patients with high LDL/HDL ratio (> 2.73) tend to be inferior OS (79.3% vs. 86.9%; P=0.001), DMFS (81.9% vs. 86.5%; P=0.030), and PFS (72.6% vs. 77.8%; P= 0.034) than those of low LDL/HDL ratio (≤2.73). In multivariate analysis, baseline HDL was found to be a significant prognostic factor for LRFS (HR= 0.65; 95% CI, 0.45-0.93; P= 0.019) and PFS (HR=0.75; 95% CI, 0.58-0.98; P= 0.034). Conclusions: Circulating HDL is significantly associated with treatment outcomes in patients with locoregionally advanced NPC. We suggest that HDL measurements will be of great clinical significance in the management of NPC.

Abstract Background Previous studies have reported radiotherapy interruption (RTI) is associated with poor local control in two-dimensional radiotherapy (2DRT) era. However, it remains unclear whether RTI still affects local control for advanced T stage (T3–4) in the intensity-modulated radiation therapy (IMRT) era. We aim to evaluate whether RTI affects local control for T3–4 NPC treated with definitive IMRT. Methods In this observational prospective study, 447 T3–4 NPC patients treated with IMRT plus concurrent chemotherapy were included. All patients completed the planned radiotherapy course, and RTI was defined as the actual time taken to finish the prescribed course of radiotherapy minus the planned radiotherapy time. Receiver operating characteristic (ROC) curve was used for determined the cutoff point of RTI. The effects of RTI on local control were analyzed in multivariate analysis. Results At 5 years, the local relapse-free survival (LRFS) and overall survival (OS) rates were 93.7 and 85.7%, respectively. The cutoff RTI for LRFS was 5.5 days by ROC curve. Compared to patients with RTI > 5 days, patients with RTI ≤ 5 days had a significantly lower rate of LRFS (97% vs. 83%; P

Abstract Background According to the 7th edition of the American Joint Committee on Cancer (AJCC) staging system, over 50% of patients with nasopharyngeal carcinoma (NPC) have N1 disease at initial diagnosis. However, patients with N1 NPC are relatively under-researched, and the metastasis risk of this group is not well-stratified. This study aimed to evaluate the prognostic values of gross tumor volume of metastatic regional lymph node (GTVnd) and pretreatment serum copy number of Epstein–Barr virus (EBV) DNA in predicting distant metastasis of patients with N1 NPC, and to develop an integrated prognostic model that incorporates GTVnd and EBV DNA copy number for this group of patients. Methods The medical records of 787 newly diagnosed patients with nonmetastatic, histologically proven N1 NPC who were treated at Sun Yat-sen University Cancer Center between November 2009 and February 2012 were analyzed. Computed tomography-derived GTVnd was measured using the summation-of-area technique. Blood samples were collected before treatment to quantify plasma EBV DNA. The receiver operating characteristic (ROC) curve analysis was used to evaluate the cut-off point for GTVnd, and the area under the ROC curve was used to assess the predicted validity of GTVnd. The survival rates were assessed by Kaplan–Meier analysis, and the survival curves were compared using a log-rank test. Multivariate analysis was conducted using the Cox proportional hazard regression model. Results The 5-year distant metastasis-free survival (DMFS) rates for patients with GTVnd > 18.9 vs. ≤ 18.9 mL were 82.2% vs. 93.2% (P 4000 vs. ≤ 4000 copies/mL were 83.5% vs. 93.9% (P 18.9 mL and EBV DNA copy number > 4000 copies/mL were significantly associated with poor prognosis (both P

Numerous studies have demonstrated that exposure to ambient ozone (O3) could have adverse effects on children’s respiratory health. However, previous studies mainly focused on asthma and wheezing. Evidence for allergic rhinitis and bronchitic symptoms (e.g., persistent cough and phlegm) associated with O3 is limited, and results from existing studies are inconsistent. This study included a total of 59,754 children from the seven northeastern cities study (SNEC), who were aged 2 to 17 years and from 94 kindergarten, elementary and middle schools. Information on doctor-diagnosed allergic rhinitis (AR), persistent cough, and persistent phlegm was collected during 2012–2013 using a standardized questionnaire developed by the American Thoracic Society (ATS). Information for potential confounders was also collected via questionnaire. Individuals’ exposure to ambient ozone (O3) during the four years before the investigation was estimated using a satellite-based random forest model. A higher level of O3 was significantly associated with increased risk of AR and bronchitic symptoms. After controlling for potential confounders, the OR (95% CI) were 1.13 (1.07–1.18), 1.10 (1.06–1.16), and 1.12 (1.05–1.20) for AR, persistent cough, and persistent phlegm, respectively, associated with each interquartile range (IQR) rise in O3 concentration. Interaction analyses showed stronger adverse effects of O3 on AR in children aged 7–17 years than those aged 2–6 years, while the adverse association of O3 with cough was more prominent in females and children aged 7–12 years than in males and children aged 2–6 and 13–17 years. This study showed that long-term exposure to ambient O3 was significantly associated with higher risk of AR and bronchitic symptoms in children, and the association varies across age and gender. Our findings contribute additional evidence for the importance of controlling O3 pollution and protecting children from O3 exposure.

PURPOSE: To assess the effect of adding neoadjuvant chemotherapy (NACT) to concurrent chemoradiotherapy (CCRT) in patients with locoregionally advanced nasopharyngeal carcinoma (NPC) and undetectable pretreatment Epstein-Barr virus (pEBV) DNA. MATERIALS AND METHODS: We enrolled 639 NPC patients with stage II to IVB and undetectable pEBV DNA to receive CCRT with or without NACT. Radiotherapy was 2.0 to 2.27 Gy per fraction with five daily fractions per week for 6 to 7 weeks to the primary tumor and 62 to 70 Gy to the involved neck area. NACT was cisplatin (80-100 mg/m2 day 1) and 5-fluorouracil (800-1000 mg/m2, 120-hour continuous intravenous infusion) every 3 weeks for two or three cycles. CCRT was cisplatin (80-100 mg/m2 day 1) every 3 weeks for three cycles. RESULTS: For all patients, the 5-year overall survival (OS), locoregional relapse-free survival (LRFS), distant metastasis-free survival (DMFS), and progression-free survival (PFS) rates were 91.9%, 92.2%, 95.0%, and 86.4%, respectively. There was no significant difference in OS (5-year OS 90.8% [NACT + CCRT group] vs 92.7% [CCRT alone]; hazard ratio [HR] 1.24; P = .486), LRFS (HR 1.13, 95% confidence interval [CI] 0.59-2.14, P = .715), DMFS (HR 0.78, 95% CI 0.34-1.78, P = .554), or PFS (HR 1.21, 95% CI 0.75-1.95, P = .472). CONCLUSION: CCRT with or without NACT produced a good treatment outcome in patients with locoregionally advanced NPC and undetectable pEBV DNA, but NACT before CCRT did not significantly improve survival rates.

Abstract Background In the era of intensity-modulated radiotherapy (IMRT), the role of neoadjuvant chemotherapy (NACT) in treating ascending-type nasopharyngeal carcinoma (NPC) is under-evaluated. This study was to compare the efficacy of NACT followed by IMRT (NACT + RT) with the efficacy of concurrent chemoradiotherapy (CCRT) on ascending-type NPC. Methods Clinical data of 214 patients with ascending-type NPC treated with NACT + RT or CCRT between December 2009 and July 2011 were analyzed. Of the 214 patients, 98 were treated with NACT followed by IMRT, and 116 were treated with CCRT. The survival rates were assessed using Kaplan–Meier analysis, and the survival curves were compared using a log-rank test. Results The 4-year overall survival, locoregional failure-free survival, distant failure-free survival, and failure-free survival rates were not significantly different between the two groups (all P > 0.05). However, patients in the CCRT group exhibited more severe acute adverse events than did patients in the NACT + RT group during radiotherapy, including leukopenia (30.2% vs. 15.3%, P = 0.016), neutropenia (25.9% vs. 11.2%, P = 0.011), and mucositis (57.8% vs. 40.8%, P = 0.028). After radiotherapy, patients in the CCRT group exhibited significantly higher rates of xerostomia (21.6% vs. 10.2%, P = 0.041) and hearing loss (17.2% vs. 6.1%, P = 0.023). Conclusions The treatment outcomes of the NACT + RT and CCRT groups were similar; however, CCRT led to higher rates of acute and late toxicities. NACT + RT may therefore be a better treatment strategy for ascending-type NPC.

Background: The aim of this study was to evaluate the benefits from the addition of induction chemotherapy (IC) to concurrent chemoradiotherapy (CCRT) in N2-3 nasopharyngeal carcinoma (NPC). Methods: A total of 3089 patients with nonmetastatic NPC, staged as N2-3 were retrospectively reviewed. IC contained cisplatin (80 mg/m 2 ) with 5-fluorouracil (800 mg/m 2 /day over 120 h), or cisplatin (80 mg/m 2 ) with docetaxel (80 mg/m 2 ), or cisplatin (60 mg/m 2 ) with 5-fluorouracil (600 mg/m 2 over 120 h), and docetaxel (60 mg/m 2 ) administered at 3-week intervals for two or three cycles. Concurrent chemotherapy consisted of cisplatin (80 or 100 mg/m 2 ) given in weeks 1, 4, and 7 of radiotherapy, or cisplatin (40 mg/m 2 ) given weekly during radiotherapy. Overall, three well-matched risk groups (low, intermediate, and high risk) were created using propensity score matching, and IC plus CCRT was compared with CCRT in each risk group. Our primary endpoint was distant metastasis-free survival (DMFS). Results: A nomogram for DMFS was established with good prognostic accuracy (C-index, 0.69; 95% confidence interval, 0.64–0.73). The survival curves for low, intermediate, and high-risk groups stratified by the nomogram were significantly different between all three risk groups, with corresponding 5-year DMFS rates of 90.7%, 79.4%, and 64.9%, respectively ( p < 0.001). IC plus CCRT was significantly associated with superior DMFS as compared with CCRT alone (69.5% versus 56.7%, p = 0.004) in the high-risk group. However, no significant difference between IC plus CCRT and CCRT was observed ( p = 0.831 and 0.608, respectively) in the intermediate and low-risk groups. Conclusions: Our findings can help accurately guide the treatment of individual patients with advanced N-stage NPC.

Distant metastasis has become the predominant model of treatment failures in patients with locoregionally advanced nasopharyngeal carcinoma. Effort should therefore be made to stratify locoregionally advanced nasopharyngeal carcinoma patients into different groups based on the risk of metastasis to improve prognosis and tailor individualized treatments. This study aims to assess the value of primary gross tumor volume and the maximum standardized uptake value for predicting distant metastasis–free survival of patients with locoregionally advanced nasopharyngeal carcinoma. A total of 294 locoregionally advanced nasopharyngeal carcinoma patients who were identified from prospectively maintained database and underwent fluor-18-fluorodeoxyglucose positron emission tomography/computed tomography imaging before treatment were included. The maximum standardized uptake value was recorded for the primary tumor (SUVmax-P) and neck lymph nodes (SUVmax-N). Computed tomography-derived primary gross tumor volume was measured using the summation-of-area technique. At 5 years, the distant metastasis–free survival rate was 83.7%. The cut-off of the SUVmax-P, SUVmax-N, and primary gross tumor volume for distant metastasis–free survival was 8.95, 5.75, and 31.3 mL, respectively, by receiver operating characteristic curve. In univariate analysis, only SUVmax-N (hazard ratio: 7.01; 95% confidence interval: 1.70–28.87; p

PURPOSE:To compare the outcomes of patients with ascending type (T4&N0-1) and descending type (T1-2&N3) of nasopharyngeal carcinoma (NPC) treated with concurrent chemoradiotherapy (CCRT), neoadjuvant chemotherapy (NACT) + intensity-modulated radiotherapy (RT) or NACT + CCRT. METHODS:Retrospective analysis of 839 patients with ascending or descending types of NPC treated at a single institution between October 2009 to February 2012. CCRT was delivered to 236 patients, NACT + RT to 302 patients, and NACT + CCRT to 301 patients. RESULTS:The 4-year overall survival rate, distant metastasis-free survival rate, local relapse-free survival rate, nodal relapse-free survival rate, loco-regional relapse-free survival rate, and progression free survival rate were 75.2% and 73.4% (P = 0.114), 85.7% and 74.1% (P = 0.008), 88.8% and 97.1% (P = 0.013), 96.9% and 94.1% (P = 0.122), 86.9% and 91.2% (P = 0.384), 73.7% and 66.2% (P = 0.063) in ascending type and descending type. Subgroup analyses indicated that NACT + RT significantly improved distant metastasis-free survival rate and progression-free survival rate when compared with CCRT in the ascending type, and there were no significant differences between the survival curves of NACT +RT and NACT + CCRT. For descending type, there were no significant differences among the survival curves of NACT +RT, CCRT, and NACT + CCRT groups, and the survival benefit mainly came from CCRT. CONCLUSIONS:Compared with NACT + CCRT or CCRT, NACT + RT may be a reasonable approach for ascending type. Although concurrent chemotherapy was effective in descending type, NACT + CCRT may be a more appropriate strategy for descending type.

Purpose This study aimed to develop web-based nomograms to precisely predict survival outcomes in patients with non-metastatic nasopharyngeal carcinoma (NPC) in an endemic area. Materials and Methods A total of 10,126 patients who underwent radical intensity-modulated radiotherapy at Sun Yat-sen University Cancer Center (SYSUCC) from 2009 to 2015 were analyzed. We assigned patients into a training cohort (SYSUCC-A, n=6,751) and an internal validation cohort (SYSUCC-B, n=3,375) based on computer-generated random numbers. Patients collected from Wuzhou Red Cross Hospital (WZRCH) between 2012 and 2015 were used as the independent external validation cohort (WZRCH, n=450). Concordance index (C-index) was used to determine predictive accuracy and discriminative ability for the nomogram. The web-based clinicopathologic prediction models for predicting survival were based on Cox regression. Results The C-indexes for SYSUCC-A, SYSUCC-B, and WZRCH cohorts for the established nomograms to predict 3-year overall survival (OS) was 0.736, 0.715, and 0.691. Additionally, C-indexes to predict 3-year distant metastasis-free survival (DMFS) was 0.717, 0.706, and 0.686, disease-free survival (DFS) was 0.713, 0.697, and 0.656, local relapse-free survival was 0.695, 0.684, and 0.652, and regional relapse-free survival was 0.672, 0.650, and 0.616. The calibration plots showed great agreement between nomogrampredicted 3-year survival outcomes and actual 3-year survival outcomes. Moreover, C-indexes of the nomograms for OS, DMFS, and DFS were significantly superior than TNM stage (p < 0.001 for all). Conclusion These user-friendly nomograms can precisely predict survival endpoints in patients with non-metastatic NPC. They may serve as a useful tool for providing patient counseling and help physicians to make individual follow-up plans. [ABSTRACT FROM AUTHOR]

Purpose We aim to examine nasopharyngeal carcinoma (NPC) characteristics and survival outcomes in patients aged 70 years and older in the intensity-modulated radiotherapy (IMRT) era. Materials and Methods From 2006 to 2013, 126 non-metastatic NPC patients aged ⩾ 70 years who were treated with IMRT +/- chemotherapy were included. Adult Comorbidity Evaluation 27 (ACE-27) was used to measure patient comorbidities. The overall survival (OS) and cancer-specific survival (CSS) were calculated with the Kaplan-Meier method, and differences were compared using the log-rank test. The Cox proportional hazards model was used to carry out multivariate analyses. Results For the entire group, only two patients (1.6%) presented stage I disease, and up to 84.1% patients had stage III-IVB disease. All patients had a comorbidity score of 0 in 24 (19.0%), 1 in 45 (35.7%), 2 in 42 (33.3%), and 3 in 15 (11.9%) patients. The main acute grade during radiotherapy was 3-4 adverse events consisting of mucositis (25.4%), bone marrow suppression (16.7%), and dermatitis (8.7%). After treatment, four patients (3.2%) developed temporal lobe injury. Five-year CSS and OS rates were 67.3% (95% confidence interval [CI], 58.6% to 77.4%) and 54.0% (95% CI, 45.6% to 63.9%), respectively. Five-year OS was significantly higher for ACE-27 score 0-1 than ACE-27 score 2-3 (72.9% and 39.9%, respectively; p < 0.001). Multivariate analyses showed ACE-27 score 0-1 was significantly associated with superior OS (hazard ratio [HR], 3.02,95% CI, 1.64 to 5.55,p < 0.001). In addition, the rate of OS was higher for stage I-III than that of stage IV, with borderline significance (HR, 1.67,95% CI, 0.99 to 2.82,p=0.053). But no significant advantage was observed in OS when chemotherapy was used (p > 0.05). Conclusion Our findings suggest IMRT +/- chemotherapy has a manageable toxicity and provides an acceptable survival in patients aged ⩾ 70 years with NPC. ACE-27 score was significantly associated with survival outcomes in this group population. [ABSTRACT FROM AUTHOR]

Rab11‑family interacting proteins (Rab11‑FIPs) are associated with the progression of various tumors; however, their expression and clinical significance in colorectal cancer (CRC) remains largely undetermined. In this study, the clinical implications, functions and underlying mechanisms of Rab11‑FIP4 in CRC were investigated. Immunohistochemical analysis revealed that expression of Rab11‑FIP4 was significantly increased in human CRC tissues and correlated with poor prognosis of patients with CRC. Overexpression of Rab11‑FIP4 in the CRC cell line significantly promoted cell proliferation, migration and invasion in vitro and tumor metastasis in vivo. Furthermore, the results of a co‑immunoprecipitation assay and western blot analysis demonstrated that Rab11‑FIP4 interacted with Rab11 and insulin‑like growth factor 1 receptor, and increased the phosphorylation of extracellular signal‑regulated kinase 1/2 and AKT serine/threonine kinase. In addition, hypoxia contributed to the upregulation of Rab11‑FIP4 expression via hypoxia‑inducible factor‑1α activation of the Rab11‑FIP4 promoter. In conclusion, the results of the present study suggest that Rab11‑FIP4 may act as an oncogene in CRC, and may be a potential therapeutic target for the treatment of patients with CRC. [ABSTRACT FROM AUTHOR]

Distant metastasis has become the predominant model of treatment failures in patients with locoregionally advanced nasopharyngeal carcinoma. Effort should therefore be made to stratify locoregionally advanced nasopharyngeal carcinoma patients into different groups based on the risk of metastasis to improve prognosis and tailor individualized treatments. This study aims to assess the value of primary gross tumor volume and the maximum standardized uptake value for predicting distant metastasis--free survival of patients with locoregionally advanced nasopharyngeal carcinoma. A total of 294 locoregionally advanced nasopharyngeal carcinoma patients who were identified from prospectively maintained database and underwent fluor-18-fluorodeoxyglucose positron emission tomography/computed tomography imaging before treatment were included. The maximum standardized uptake value was recorded for the primary tumor (SUVmax-P) and neck lymph nodes (SUVmax-N). Computed tomography-derived primary gross tumor volume was measured using the summation-of- area technique. At 5 years, the distant metastasis--free survival rate was 83.7%. The cut-off of the SUVmax-P, SUVmax-N, and primary gross tumor volume for distant metastasis--free survival was 8.95, 5.75, and 31.3 mL, respectively, by receiver operating characteristic curve. In univariate analysis, only SUVmax-N (hazard ratio: 7.01; 95% confidence interval: 1.70-- 28.87; p < 0.01) and clinical stage (hazard ratio: 3.03; 95% confidence interval: 1.67--5.47; p = 0.007) were confirmed as independent predictors of distant metastasis--free survival. A prognostic model was derived by SUVmax-N and clinical stage: low risk (SUVmax-N < 5.75 regardless of clinical stage), medium risk (stage III and SUVmax-N ≥ 5.75), and high risk (stage IV and SUVmax-N ≥ 5.75). Multivariate analysis revealed that SUVmax-N and the prognostic model remained independent prognostic factors for distant metastasis--free survival (p = 0.023 and p < 0.001, respectively), but the clinical stage became insignificant (p = 0.133). Furthermore, the adjusted hazard ratios for the prognostic model were higher than SUVmax-N (hazard ratio = 6.27 vs 5.21, respectively). In summary, compared with SUVmax-P, SUVmax-N may be a better predictor of distant metastasis--free survival for patients with locoregionally advanced nasopharyngeal carcinoma. Combining SUVmax-N with clinical stage gives a more precise picture in predicting distant metastasis. [ABSTRACT FROM AUTHOR]

By transferring the judgment of convex functions of several variables into the judgment of convex functions of one variable, the authors discuss the convexity of some convex functions of several variables.