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Juvenile polyposis syndrome (JPS) is an autosomal dominant, inherited disorder caused by pathogenic germline variants of mainly SMAD4 or BMPR1A genes. Some patients with JPS, especially with SMAD4 variants, also develop hereditary, hemorrhagic telangiectasia (HHT). HHT is also an autosomal dominant inherited disorder. Herein, we identified a novel germline pathogenic variant of the SMAD4 in a Japanese family with JPS and HHT. A six-base pair deletion in the SMAD4 gene (NM_005359.6:c.1495_1500delTGCATA) was identified in the patients. Two amino acids are deleted from SMAD4 protein (p.Cys499_Ile500del), which are located in MSH2 domain essential for the binding with SMAD3. This is a novel variant that has not been registered in any database surveyed. Amino acid structural analysis predicted significant changes in the secondary and three-dimensional structures in the vicinity of the two amino acids’ deletion. The variant is classified as ‘Likely Pathogenic’ according to the American College of Medical Genetics and Genomics guidelines.

Trastuzumab-induced cardiotoxicity interferes with continued treatment in approximately 10% of patients with ErbB2-positive breast cancer, but its mechanism has not been fully elucidated. In this study, we recruited trastuzumab-treated patients with ≥30% reduction in left ventricular ejection fraction (SP) and noncardiotoxic patients (NP). From each of these patients, we established three cases of induced pluripotent stem cell-derived cardiomyocytes (pt-iPSC-CMs). Reduced contraction and relaxation velocities following trastuzumab treatment were more evident in SP pt-iPSC-CMs than NP pt-iPSC-CMs, indicating the cardiotoxicity phenotype could be replicated. Differences in ATP production, reactive oxygen species, and autophagy activity were observed between the two groups. Analysis of transcripts revealed enhanced kallikrein5 expression and pro-inflammatory signaling pathways, such as interleukin-1β, in SP pt-iPSC-CMs after trastuzumab treatment. The kallilkrein5-protease-activated receptor 2 (PAR2)-MAPK signaling pathway was more activated in SP pt-iPSC-CMs, and treatment with a PAR2-antagonist suppressed interleukin-1β expression. Our data indicate enhanced pro-inflammatory responses through kallikrein5-PAR2 signaling and vulnerability to external stresses appear to be the cause of trastuzumab-induced cardiotoxicity in SP.

This study aimed to assess current trends in morbidity and mortality among patients with familial adenomatous polyposis (FAP). These data can be used for optimal surveillance and management of such patients.Data (November 2001 and April 2020) of genetically confirmed patients with FAP (n = 87) and their first-degree relatives with FAP phenotype (n = 20) were extracted from the Saitama Medical Center database. Standardized mortality ratio (SMR) and standardized incidence ratio (SIR) were estimated using indirect method.Overall, 46 men and 61 women were included; the median age at FAP diagnosis was 28.0 years for both. The SMR for all causes of death was 47.7 (95% confidence interval [CI] 19.1-98.2) in women and 26.5 (95% CI 9.73-57.8) in men. The SIR for colorectal cancer (CRC) was 860 (95% CI 518-1340) in women and 357 (95% CI 178-639) in men. The SMR for CRC was 455 (95% CI 93.7-1330) in women and 301 (95% CI 62.0-879) in men. Thirteen patients died during the observation period, and CRC was the leading cause of death (46%). Other causes of death included desmoid tumor (n = 2), small intestinal cancer (n = 2), ovarian cancer (n = 1), duodenal cancer (n = 1), and sepsis (n = 1).The mortality ratio, estimated using SMR, remained high. CRC was the leading cause of death, whereas almost half of the causes of deaths were extra-colonic tumors. Life-long management of extra-colonic diseases may improve the prognosis in these patients.

Supplementary Table 1 from RET/PTC Rearrangements Preferentially Occurred in Papillary Thyroid Cancer among Atomic Bomb Survivors Exposed to High Radiation Dose

A major early event in papillary thyroid carcinogenesis is constitutive activation of the mitogen-activated protein kinase signaling pathway caused by alterations of a single gene, typically rearrangements of the RET and NTRK1 genes or point mutations in the BRAF and RAS genes. In childhood papillary thyroid cancer, regardless of history of radiation exposure, RET/PTC rearrangements are a major event. Conversely, in adult-onset papillary thyroid cancer among the general population, the most common molecular event is BRAFV600E point mutation, not RET/PTC rearrangements. To clarify which gene alteration, chromosome aberration, or point mutation preferentially occurs in radiation-associated adult-onset papillary thyroid cancer, we have performed molecular analyses on RET/PTC rearrangements and BRAFV600E mutation in 71 papillary thyroid cancer cases among atomic bomb survivors (including 21 cases not exposed to atomic bomb radiation), in relation to radiation dose as well as time elapsed since atomic bomb radiation exposure. RET/PTC rearrangements showed significantly increased frequency with increased radiation dose (Ptrend = 0.002). In contrast, BRAFV600E mutation was less frequent in cases exposed to higher radiation dose (Ptrend < 0.001). Papillary thyroid cancer subjects harboring RET/PTC rearrangements developed this cancer earlier than did cases with BRAFV600E mutation (P = 0.03). These findings were confirmed by multivariate logistic regression analysis. These results suggest that RET/PTC rearrangements play an important role in radiation-associated thyroid carcinogenesis. [Cancer Res 2008;68(17):7176–82]

Supplementary Figure Legend from RET/PTC Rearrangements Preferentially Occurred in Papillary Thyroid Cancer among Atomic Bomb Survivors Exposed to High Radiation Dose

Supplementary Table 2 from RET/PTC Rearrangements Preferentially Occurred in Papillary Thyroid Cancer among Atomic Bomb Survivors Exposed to High Radiation Dose

Supplementary Figure 1 from RET/PTC Rearrangements Preferentially Occurred in Papillary Thyroid Cancer among Atomic Bomb Survivors Exposed to High Radiation Dose

Background: In advanced or metastatic ovarian cancer patients, the therapeutic impact of molecular targeted agents and immunotherapy is limited, and current chemotherapeutic algorithm is still far from personalized medicine. We recently demonstrated that intraperitoneal carboplatin with dose-dense paclitaxel (ddTCip) therapy is a promising front-line chemotherapy even in the patients with residual peritoneal tumors, which led us to this theranostic study for biomarker discovery to realize the precision medicine (ID: UMIN000001713 on Feb 16 th , 2009). Methods: We first validated previously suggested markers (41 genes and 3 predictive models for the therapeutic efficacy and 31 polymorphisms for the toxicity), sought out more active effective biomarkers through genome-wide transcriptome and genotyping analyses, and then developed multiplex statistical prediction models for progression free-survival (PFS) and toxicity. Multiple regression analysis following forward stepwise method and Classification and Regression Trees (CART) algorithm were mainly employed to develop multiplex prediction models. Results: The association analyses with PFS in 76 patients followed by the validation study using data sets in 189 patients published in The Cancer Genome Atlas revealed that SPINK1 expression could be a possible predictive biomarker of ddTCip efficacy even when used alone, and multiple regression analyses provided a potent efficacy prediction model using expression data of 5 genes. SPINK1 appeared to be a critical resistant determinant of ddTCip therapy, which indicates the potential of SPINK1 also to be a novel therapeutic target. As for the toxicity prediction, ABCB1rs1045642 and ERCC1rs11615 polymorphisms appeared to closely associate with grade2-4 hematologic toxicity and peripheral neuropathy, respectively. We further successfully composed robust multiplex prediction models for the adverse events-CART models using a total of 4 genotype combinations and further powerful multiple regression models using 15 polymorphisms on 12 genes-. Conclusions: We newly proposed SPINK1 expression as a powerful predictive biomarker of the efficacy for ddTCip therapy and confirmed the predictive values of ABCB1 and/or ERCC1 polymorphisms for the toxicity. Multiplex prediction models composed herein were also found to work well for the prediction of therapeutic response. These may raise the potential to realize a precision medicine in the essential treatment for metastatic ovarian cancer patients.

Background: In advanced or metastatic ovarian cancer patients, the therapeutic impact of molecular targeted agents and immunotherapy is limited, and current chemotherapeutic algorithms are still far from personalized medicine. We recently demonstrated that intraperitoneal carboplatin with dose-dense paclitaxel (ddTCip) therapy is a promising front-line chemotherapy even in patients with residual peritoneal tumors, which led us to this theranostic study for biomarker discovery to realize precision medicine (ID: UMIN000001713 on Feb 16th, 2009). Methods: We first validated previously suggested markers (41 genes and 3 predictive models for therapeutic efficacy and 31 polymorphisms for toxicity), sought out more active effective biomarkers through genome-wide transcriptome and genotyping analyses, and then developed multiplex statistical prediction models for progression-free survival (PFS) and toxicity. Multiple regression analysis following the forward stepwise method and the classification and regression tree (CART) algorithm were mainly employed to develop multiplex prediction models. Results: The association analyses with PFS in 76 patients followed by the validation study using data sets in 189 patients published in The Cancer Genome Atlas revealed that SPINK1 expression could be a possible predictive biomarker of ddTCip efficacy even when used alone, and multiple regression analyses provided a potent efficacy prediction model using expression data of 5 genes. SPINK1 appeared to be a critical resistant determinant of ddTCip therapy, which indicates the potential of SPINK1 as a novel therapeutic target. For toxicity prediction, ABCB1 rs1045642 and ERCC1 rs11615 polymorphisms appeared to be closely associated with grade 2-4 hematologic toxicity and peripheral neuropathy, respectively. We further successfully composed robust multiplex prediction models for adverse events - CART models using a total of 4 genotype combinations and further powerful multiple regression models using 15 polymorphisms on 12 genes-. Conclusions: We newly proposed SPINK1 expression as a powerful predictive biomarker of the efficacy of ddTCip therapy and confirmed the predictive values of ABCB1 and/or ERCC1 polymorphisms for toxicity. The multiplex prediction models composed herein were also found to work well for the prediction of therapeutic response. These findings may raise the potential to realize precision medicine in the essential treatment for metastatic ovarian cancer patients.

The prevalence of Lynch syndrome (LS)-associated DNA mismatch repair (MMR)-deficient bladder cancer (BC) has scarcely been investigated. Immunohistochemistry for four MMR proteins (MLH1, MSH2, MSH6, and PMS2) was performed in formalin-fixed paraffin-embedded (FFPE) sections prepared from the resected specimens of 618 consecutive newly diagnosed BC cases. Genetic/epigenetic analyses were performed in patients displaying the loss of any MMR proteins in the tumor. Of the 618 patients, 9 (1.5%) showed the loss of MMR protein expression via immunohistochemistry; specifically, 3, 3, 2, and 1 patients displayed the loss of MLH1/PMS2, PMS2, MSH6, and MSH2/MSH6, respectively. All nine patients were male with a median age of 68 years (63–79 years). One had been previously diagnosed as having LS with an MSH2 variant. Genetic testing demonstrated the presence of a pathogenic PMS2 variant (n = 1), a variant of uncertain significance in MSH2 (n = 1), and no pathogenic germline variants of the MMR genes (n = 1). One patient with MSH6-deficient BC did not complete the genetic testing because of severe degradation of DNA extracted from the FFPE specimen, but the patient was strongly suspected to have LS because of their history of colon cancer and MSH6-deficient upper urinary tract cancer. There remained a possibility that the remaining four patients who refused genetic testing had LS. The prevalence of LS-associated MMR-deficient BC was estimated to be 0.6–1.1% among unselected BC cases.

Familial adenomatous polyposis (FAP), an autosomal dominant disorder characterized by multiple colonic polyps, is caused by a germline pathogenic variant of the APC gene. However, this variant is not detected in up to 30% of patients with the adenomatous polyposis phenotype. We performed next-generation sequencing (NGS) to identify the causative genes in FAP patients with 10 or more polyps. For patients in whom the APC germline variant was not able to be identified, we screened for APC mosaicism using high-coverage NGS of APC with DNA from leucocytes and/or frozen tissue. The pathogenic APC germline variant was found in 93.3%, 71.6%, and 17.1% of patients with profuse-type polyposis, sparse-type polyposis, and oligo-polyposis, respectively. The APC germline variant detection rate in patients with FAP-related diseases was 69.7% for fundic gland polyposis, 79.7% for duodenal adenoma, 94.7% for desmoid tumor, and 71.4% for thyroid cancer, with increasing numbers of extracolonic lesions associated with an increasing APC germline variant detection rate. A mosaic test detected nine patients with APC mosaicism. A comparison of APC-associated polyposis with APC mosaicism showed that patients with APC mosaicism had a low frequency of duodenal adenoma and a family history of colonic polyposis. We determined the detection rate of the APC germline variant by phenotype and identified APC mosaicism. Genetic testing of FAP patients is important because it can help with surgical decision-making, monitoring, and genetic counseling. Furthermore, genetic testing by NGS proved to be an effective method of detecting APC germline variants.

Background The prevalence and molecular characteristics of deficient mismatch repair prostate cancer in the Japanese population have scarcely been investigated. Methods Immunohistochemistry for mismatch repair proteins (MLH1, MSH2, MSH6 and PMS2) was performed in formalin-fixed paraffin-embedded sections prepared from resected primary prostate cancers in patients who underwent prostatectomy at our institution between January 2001 and May 2016. Genetic and/or epigenetic alterations of mismatch repair genes were investigated in patients with any loss of mismatch repair protein expression in the tumour. Results Of the 337 patients, four (1.2%) showed loss of mismatch repair protein expression on immunohistochemistry. All four patients showed loss of both MSH2 and MSH6 protein expression. Genetic testing was performed in two of the four patients, demonstrating no pathogenic germline alterations were present. In each of these two patients, at least one somatic alteration inactivating MSH2 without MSH2 hypermethylation was identified, leading to the diagnosis of supposed ‘Lynch-like syndrome’. Patients with deficient mismatch repair prostate cancer were at a significantly higher stage (pT2pN0 vs. pT3-4pN0/pTanypN1, P = 0.02) and had a greater Gleason score ( Conclusions The prevalence of deficient mismatch repair prostate cancer in the Japanese hospital-based prostatectomized population was extremely low. To improve screening efficacy for deficient mismatch repair prostate cancer, screening candidates can be limited to patients with locally advanced, node-positive and/or Gleason score of 8 or greater prostate cancer. Universal tumour screening for Lynch syndrome seems ineffective in patients with prostate cancer.

We investigated the prevalence and characteristics of defective mismatch repair (dMMR) in colorectal cancer (CRC) patients who would potentially benefit from anti-programmed cell death protein 1 (PD-1) immunotherapy. Medical records were obtained and reviewed for 1147 patients who underwent surgical resection of stage I–IV CRC, in whom universal screening for Lynch syndrome using immunohistochemistry for MMR proteins had been undertaken. The molecular characteristics of dMMR CRCs were also investigated. Defective MMR accounted for 5.2% of stage I–IV CRC patients, including 12 (1.0% of all CRC patients) who had stage IV disease or recurrence after curative resection (n = 6 each). These 12 patients included patients with LS (n = 3) and Lynch-like syndrome (n = 1). Defective MMR tumors were predominantly located in the right-sided colon (P

Collagen type XVII α1 (COL17A1) encodes a hemidesmosomal protein at the epidermal-dermal junction and its variants are implicated in blistering skin diseases. Recent experiments in rodents revealed that Col17a1 has critical roles in stem cells of epidermal origin and in melanoma carcinogenesis. In the present study, it was investigated whether germline variants in COL17A1 are associated with skin cancer and other cancer types using indexed consecutive autopsy cases from the Japanese Geriatric Single Nucleotide Polymorphism database (n=2,343; mean age, 80 years). The database included 12 patients with skin cancer. A total of 53 COL17A1 missense variants on an exome chip were analyzed. One variant, p.Ser1029Ala (rs118166857), which had a minor allele frequency of 1.0%, exhibited a nominal positive sign of association with skin cancer [Fisher's exact P=0.002, odds ratio (OR)=16.93, 95% CI: 4.44-64.64]. This variant was detected in 2/2 patients with mucosal malignant melanoma (mMM) and 1/3 patients with extramammary Paget's disease, and in none of the patients with non-melanoma cancer, e.g., squamous cell and basal cell carcinoma. Other cancer types were searched in the database and the p.Ser1029Ala variant was indicated to be nominally associated with breast cancer (P=0.006, OR=4.17, 95% CI: 1.72-10.11). In the two mMM cases, targeted exome sequencing of 55 cancer-predisposing genes (including tumor protein 53, BRCA1/2 and mismatch repair genes) detected no apparent pathogenic variants, but revealed variants of unknown significance in axin 2, DNA directed polymerase ζ catalytic subunit and contactin 6. Since COL17A1 provides a niche for melanocyte stem cells, it was hypothesized that the p.Ser1029Ala variant in the COL17A1 ectodomain may affect the microenvironment, e.g., the cell competition. This is a working hypothesis generated from human autopsy cases and warrants further epidemiological and molecular biological validation.

We previously demonstrated that expression of a Krüppel-like zinc finger transcription factor, GLIS1, dramatically increases under hypoxic conditions via a transcriptional mechanism induced by HIF-2α cooperating with AP-1 members. In this study, we focused on the functional roles of GLIS1 in breast cancer. To uncover its biological function, the effects of altered levels of GLIS1 in breast cancer cell lines on cellular growth, wound-healing and invasion capacities were assessed. Knockdown of GLIS1 using siRNA in BT-474 cells resulted in significant growth stimulation under normoxia, while attenuation was found in the cell invasion assay under hypoxic conditions. In MDA-MB-231 cells expressing exogenous 3xFLAG-tagged GLIS1, GLIS1 attenuated cell proliferation and enhanced cell mobility and invasion capacities under normoxia. In addition, breast cancer cells expressing GLIS1 acquired resistance to irradiation. Whole transcriptome analysis clearly demonstrated that downstream signals of GLIS1 are related to various cellular functions. Among the genes with increased expression, we focused on WNT5A. Knockdown of WNT5A indicated that enhancement of acquired cell motility in the MDA-MB-231 cells expressing GLIS1 was mediated, at least in part, by WNT5A. In an analysis of publicly available data, patients with estrogen receptor-negative breast cancer showing high levels of GLIS1 expression showed much worse prognosis than those with low levels. In summary, hypoxia-induced GLIS1 plays significant roles in breast cancer cells via regulation of gene expression related to cell migration and invasion capacities, resulting in poorer prognosis in patients with advanced breast cancer.

Background We evaluated the efficacy of intraperitoneal (IP) carboplatin in combination with dose-dense paclitaxel (ddTCip) for suboptimal residual ovarian cancer. Methods This was a phase 2 study to evaluate ddTCip. Patients with stage II–IV ovarian carcinoma, who underwent primary cytoreductive surgery and had radiologically evaluable disease after surgery, were eligible to participate in this study. IP carboplatin (AUC = 6) was administered on day 1, and intravenous paclitaxel (80 mg/m2) was administered on days 1, 8 and 15. The primary endpoint was response rate. Secondary endpoints included progression-free survival (PFS), overall survival (OS) and safety. Interval- debulking surgery followed by the same regimen was allowed when indicated. Results A total of 117 patients were considered eligible for this study prior to surgery and temporarily registered. Of the 117 patients, 76 patients met the inclusion criteria and were enrolled in this study. Fifty-nine (83.1%) patients had objective clinical responses. Median PFS and OS were 18.3 and 55.5 months, respectively. Sixty-four (84.2%) patients had grade 3/4 neutropenia, 43 (56.5%) patients had anaemia and 17 (22.4%) patients had thrombocytopenia. Port-related adverse events occurred in nine (11.8%) patients. Conclusions Front-line chemotherapy with ddTCip therapy appears safe and effective, even for patients with suboptimal residual ovarian cancer. Trial registration UMIN Clinical Trials Registry (ID: UMIN000001713) on February 16th, 2009.

BackgroundThe prevalence of Lynch syndrome and the use of universal tumor screening to identify Lynch syndrome among unselected patients with upper urinary tract urothelial carcinoma, which is associated with Lynch syndrome, have not been closely investigated yet.MethodsA total of 166 tumors from 164 upper urinary tract urothelial carcinoma patients were tested for microsatellite instability and expression of mismatch repair proteins (MLH1, MHS2, MSH6 and PMS2) by immunohistochemistry. Genetic testing was performed for patients suspected of having Lynch syndrome. Clinicopathological factors, including familial and personal cancer history associated with mismatch repair deficiency, were evaluated.ResultsThe frequency of high-level microsatellite instability and loss of at least one mismatch repair protein was 2.4% (4/164); the microsatellite instability and immunohistochemistry results showed complete concordance. Of these four patients, three were genetically proven to have Lynch syndrome, while the remaining one was highly suggestive for Lynch syndrome based on their personal cancer history. Univariate analysis showed that ageConclusionsThe prevalence of Lynch syndrome among unselected upper urinary tract urothelial carcinoma patients was at least 1.8% in our study population. The screening efficacies of the microsatellite instability test and immunohistochemistry appear equivalent. Universal tumor screening may be a valid approach; however, selective screening methods that consider factors associated with mismatch repair loss/high-level microsatellite instability tumors require further investigation.

Approximately 30% patients with stage III colon cancer (CC) develop local recurrence and/or distant metastasis, even if postoperative adjuvant chemotherapy with oxaliplatin plus 5-fluorouracil and leucovorin (5-FU/LV) has been completed. In the present study, molecular analysis was performed to identify molecular markers of tumor recurrence in patients with stage III CC receiving oxaliplatin-based adjuvant chemotherapy. The FACOS study was conducted as a phase II study to evaluate the safety and efficacy of oxaliplatin-based treatment for stage III CC patients. Of the 132 CC patients enrolled in the present study, gene expression analysis using a microarray was conducted in 51 patients. Of these 51 patients, 6 developed recurrence within 5 years. The topmost 5% genes that showed differential expressions between cases that developed/did not develop recurrence were selected, and a set of predictive molecular markers for recurrence was identified. Of the 34,694 genes in the microarray, 1,734 genes were extracted as topmost 5% genes showing differential expressions between cases with and without recurrence. Among these, 10 genes, includingADH1A, ADH1C, CA12, CHP2, HMGCS2, SNAR-A1, TPI1, MS4A12, PLA2G10 and PTPRO, were identified as markers that could clearly divide patients with and without recurrence. Although several prediction models of tumor recurrence have been reported for CC, the set of 10 genes that the present study identified may be useful to predict the risk of recurrence in stage III CC patients receiving oxaliplatin-based adjuvant chemotherapy. Based on these results, high-risk patients with CC should be carefully observed to detect tumor recurrence during the follow-up period.

Trio-next generation sequencing is useful to identify undiagnosed inherited diseases. We have attended a patient with trigenic ADH5/ALDH2/ADGRV1 pathogenic variants, which caused two distinct diseases, myelodysplastic syndrome and Usher syndrome. Whole genome sequencing of peripheral blood from the patient and his parents were applied to identify disease-causing genes. Sanger sequencing was performed to validate the identified ADH5/ALDH2/ADGRV1 variants. Our results identified disease-associated variants in ADGRV1 (disease inheritance autosomal recessive) and in ADH5 (disease inheritance also autosomal recessive) and a variant in ALDH2 (disease inheritance autosomal dominant). Although the variants identified in ADH5 and ALDH2 have been reported, their co-existence in association with disease-causing variation in a third gene has not. They broaden the spectrum of ADGRV1 in Usher syndrome. Findings on next generation sequencing guided rapid and accurate diagnosis, resulting in patient-tailored therapeutic intervention., Highlights • Trigenic ADH5 / ALDH2 / ADGRV1 ​variants in myelodysplastic syndrome with Usher syndrome were identified. • Two novel pathogenic frameshift variants in ​ADGRV1 ​in compound heterozygous state with Usher syndrome type II were described. • Findings on next generation sequencing guided rapid and accurate diagnosis, resulting in patient-tailored therapy., ADH5/ALDH/ADGRV1 variants, Myelodysplastic syndrome, Trigenic mutations, Trio-next generation sequencing, Usher syndrome.

Endometrial cancer(EC)is often the sentinel cancer in women with Lynch syndrome(LS), but the actual incidence of EC as the sentinel cancer in patients with LS is not well-known in Japan. We investigated the history of malignancies and incidence of sentinel cancers in patients with LS-associated EC and their relatives. We examined 8 patients with LS-associated EC between 2005 and 2019. Five of them(63%)had suffered from a cancer other than EC, while 5(63%)had developed a cancer after EC. Seven patients(88%)had EC as the sentinel cancer, while 1(13%)developed colorectal cancer before EC. Among first-degree relatives(15 men and 23 women), 15(40%)had a history of cancer, of whom 7 were women (30%). Five women(22%)had EC, all sentinel. Among second-degree relatives(40 men, 44 women, 14 unknown), 16 (16%)had cancer. Four women(9%)had a history of cancer, of whom 2(5%)had EC, all sentinel. Although we only investigated a few LS cases, the importance of EC as the sentinel cancer was highlighted in Japanese women with LS.

The proband was a 49-year-old woman who had undergone total colectomy, ileorectostomy, and bilateral ovariectomy for the treatment of cecal(T3N0)and sigmoid colon(T4a, N2b, M1c2[Ova], Stage Ⅳc)cancers. Pathological findings revealed 6 adenomas and 2 adenocarcinoma-in-adenomas in the right colon, other than advanced colon cancers. She had a family history of colorectal cancer meeting the Amsterdam Criteria I, but none of her relatives had definite polyposis. Considering the possibility of Lynch syndrome, the microsatellite-instability test and immunohistochemistry(IHC)examination of the mismatch repair protein were performed, leading to the results of microsatellite stable and proficient mismatch repair protein expression. Therefore, we performed the multigene panel test containing 26 genes using the next-generation sequencing technology. In the APC(5q22.2)gene, a pathogenic variant(exon 12 c.994CT/p.Arg332*)was identified, leading to a diagnosis of attenuated familial adenomatous polyposis(AFAP). After disclosure of the results to the proband, the single-site variant analysis was performed on her 3 daughters. In her second and third daughters, the same variant was confirmed, and laparoscopic total colectomy was performed 23 and 35 months after the disclosure of the genetic analysis results, respectively. Currently, we are conducting periodical surveillance for the residual rectum.

The proband was a 77-year-old man who had been admitted to a local hospital for fecal occult blood. He was diagnosed with descending colon carcinoma, T4a, N1, M0, Stage Ⅲb, and rectal adenoma. He had undergone surgeries for rectal cancer at 52 years of age and cecum colon cancer at 57 years of age. Regarding his family history, 5 first-degree and 3 second- degree relatives had a history of gastrointestinal and gynecological cancers, thus meeting 2 of the 5 criteria of the revised Bethesda guidelines. The microsatellite-instability(MSI)test performed using preoperative biopsy tissues demonstrated high-frequency MSI(MSI-H). Hartmann's procedure was performed for MSI-H colon cancer under a strong suspicion of Lynch syndrome. Pathological findings were consistent with descending colon carcinoma, tub2, pT3, pN0, M0, pStage Ⅱa. He was then referred to our hospital. We performed the immunohistochemistry(IHC)analysis of the mismatch repair protein using surgical specimens. The IHC analysis revealed defective expression of the MSH2/MSH6 protein. We found a pathogenic variant in the mismatch repair gene, MSH2(c.1510+2TG), through genetic testing and finally diagnosed the patient with Lynch syndrome. After disclosure of the results to the proband, 7 relatives underwent genetic testing for the MSH2 variant. Four relatives had the same variant and were also diagnosed with Lynch syndrome. They subsequently underwent surveillance for Lynch syndrome-associated cancers. In 2 variant carriers with a history of early colorectal cancer, an early colon cancer was identified and successfully resected endoscopically. Surveillance for Lynch syndrome-associated cancer is ongoing for the proband and variant carriers.

Background The attention on mismatch repair-deficient (dMMR) gastric cancer has increased in this era of anti-PD-1 blockade therapy; however, the prevalence and molecular genetics of patients with dMMR gastric cancer have not been completely investigated. Methods Immunohistochemistry of MMR proteins (MLH1, MSH2, MSH6 and PMS2) was performed on formalin-fixed paraffin-embedded sections prepared from resected primary gastric cancers of 513 consecutive patients. Genetic and/or epigenetic alterations of the MMR genes were also investigated. Results Loss of expression of one or more MMR proteins was observed in 58 patients (11.3%); 54 patients showed loss of MLH1/PMS2, 3 patients showed loss of MLH1/PMS2/MSH6 and 1 patient showed loss of PMS2 alone. Among these 58 patients, 55 showed hypermethylation of the promoter region of MLH1. Genetic testing revealed that the remaining three patients had Lynch syndrome (n = 1) or Lynch-like syndrome (n = 2). A total of 15 patients (25.9% of all patients with dMMR gastric cancer and 2.9% of all patients with gastric cancer), including 11 patients with stage I–III dMMR gastric cancer who had recurrence and 4 patients with stage IV dMMR gastric cancer, are potential candidates for the use of anti-PD-1 blockades. Conclusions This is the first study to investigate the frequency and molecular genetic mechanisms of dMMR gastric cancer comprehensively, focusing on the benefit of using PD-1 blockades. Our observations will be beneficial in the clinical practice of metastatic gastric cancer.

Background: The Japan Multi-institutional Collaborative Cohort (J-MICC) study was launched in 2005 to examine gene–environment interactions in lifestyle-related diseases, including cancers, among the Japanese. This report describes the study design and baseline profile of the study participants. Methods: The participants of the J-MICC Study were individuals aged 35 to 69 years enrolled from respondents to study announcements in specified regions, inhabitants attending health checkup examinations provided by local governments, visitors at health checkup centers, and first-visit patients at a cancer hospital in Japan. At the time of the baseline survey, from 2005 to 2014, we obtained comprehensive information regarding demographics, education, alcohol consumption, smoking, sleeping, exercise, food intake frequency, medication and supplement use, personal and family disease history, psychological stress, and female reproductive history and collected peripheral blood samples. Results: The baseline survey included 92,610 adults (mean age: 55.2 [standard deviation, 9.4] years, 44.1% men) from 14 study regions in 12 prefectures. The participation rate was 33.5%, with participation ranging from 19.7% to 69.8% in different study regions. The largest number of participants was in the age groups of 65–69 years for men and 60–64 years for women. There were differences in body mass index, educational attainment, alcohol consumption, smoking, and sleep duration between men and women. Conclusions: The J-MICC Study collected lifestyle and clinical data and biospecimens from over 90,000 participants. This cohort is expected to be a valuable resource for the national and international scientific community in providing evidence to support longer healthy lives.

BACKGROUND/AIM Identifying patients with DNA mismatch repair-deficient (dMMR) colorectal cancer (CRC) is vital to improve treatment and identify patients with Lynch syndrome (LS). We developed a prediction model for dMMR CRC using clinicopathologic features. PATIENTS AND METHODS We reviewed the medical records of 1,147 patients who underwent resection of stage I-IV CRC in whom universal screening for LS using immunohistochemistry for MMR proteins had performed. Univariate and multivariate logistic regression analyses were used to build a prediction model of dMMR CRC. RESULTS The prevalence of dMMR CRC was 5.2%. Age (≥75 years), tumor location (right-sided colon), main histologic features (poor differentiation), maximum tumor size (≥65 mm), and stage (I/II) were independent significant variables related to dMMR. We created a formula for predicting the likelihood of dMMR, and the probability ranged from 0.2% to 83%. CONCLUSION dMMR CRC can be identified efficiently using clinicopathologic features obtained in daily clinical practice.

BackgroundThe prevalence and molecular characteristics of defective DNA mismatch repair endometrial cancers in the Japanese population have been underexplored. Data supporting clinical management of patients with Lynch-like syndrome and germline variant of uncertain significance of mismatch repair genes are still lacking.MethodsImmunohistochemistry of mismatch repair proteins (MLH1, MSH2, MSH6 and PMS2) was performed on formalin-fixed paraffin-embedded sections prepared from resected primary endometrial cancers in 395 women with a median age of 59 years. Genetic and/or epigenetic alterations of the mismatch repair genes were also investigated.ResultsLoss of expression of one or more mismatch repair proteins was observed in 68 patients (17.2%). A total of 17 out of 68 patients (25%, 4.3% of all cases) were identified as candidates for genetic testing for Lynch syndrome after excluding 51 patients with MLH1 hypermethylated cancer. Fourteen of these 17 patients subjected to genetic testing were found to have Lynch syndrome (n = 5), germline variant of uncertain significance (n = 2) or Lynch-like syndrome (n = 7). Compared with patients with Lynch syndrome, those with germline variant of uncertain significance and Lynch-like syndrome tended to demonstrate an older age at the time of endometrial cancer diagnosis (P = 0.07), less fulfillment of the revised Bethesda guidelines (P = 0.09) and lower prevalence of Lynch syndrome-associated tumors in their first-degree relatives (P = 0.01).ConclusionsThis study provides useful information for management in patients with DNA mismatch repair endometrial cancer. Specifically, cancer surveillance as recommended in patients with Lynch syndrome might not be necessary in patients with germline variant of uncertain significance and Lynch-like syndrome and their relatives.

A 48-year-old Japanese female with left hypochondralgia presented at our hospital. Esophagogastroduodenoscopy (EGD) revealed gastric cancers and carpeting fundic gland polyposis (FGPs) without Helicobacter pylori infection. Computed tomography showed multiple liver metastases. Total colonoscopy revealed a colonic tubular adenoma but not polyposis. She was diagnosed as having advanced gastric cancer with liver metastasis and received chemotherapy. Her mother had died from gastric cancer, and her elderly brother and niece had FGPs as revealed by EGD. Thus, the pedigree was diagnosed as gastric adenocarcinoma and proximal polyposis of the stomach (GAPPS). Germline mutation analysis exhibited a point mutation in exon1B of the APC gene (c.-191T > C). Adenocarcinoma showed a gastric mucinous phenotype and was positive for a somatic mutation of p53, suggesting that p53 mutation may play a role in FGPs carcinogenesis. This is the first family with GAPPS in Asia in whom germline mutation of APC exon 1B has been detected.

Background Muir-Torre syndrome (MTS) is currently considered as a clinical variant of Lynch syndrome (LS). The clinical significance of the screening of patients with MTS-associated cutaneous tumors for the identification of LS has not yet been established. In addition, the prevalence and molecular characteristics of mismatch repair (MMR) protein deficiency in such tumors has scarcely been investigated in the Japanese population. Methods Immunohistochemistry (IHC) for MMR proteins (MLH1, MSH2, MSH6 and PMS2) was performed in formalin-fixed paraffin-embedded sections prepared from 16 sebaceous neoplasms (SNs) resected from 13 patients and 32 keratoacanthomas (KAs) resected from 31 patients at our institution between January 2005 and March 2014. Tumors showing MMR protein loss were further subjected to genetic analysis for detecting the presence of germline and/or somatic alterations of the MMR genes to identify the precise molecular mechanisms underlying the protein loss. Results Among the 16 SNs resected from 13 patients, eight SNs resected from five patients (38.5%) showed loss of expression of MMR proteins (MLH1/PMS2 loss, one patient; MSH2/MSH6 loss, four patients). Genetic analyses showed a pathogenic germline MSH2 mutation in one patient, somatic hypermethylation of the MLH1 promoter region in one patient, and somatic alterations of MSH2 without detectable germline mutations of MSH2 in three patients. None of the KAs examined in the study showed any loss of MMR protein expression. Conclusions The efficacy of routine screening of cutaneous neoplasms known to be associated with MTS by IHC for MMR proteins to identify LS may be fairly limited. MMR protein loss as determined by IHC in SNs is not always diagnostic of LS, and appears, in most cases, to be a result of somatic inactivation of the MMR genes.