Laparoscopic or Robotically Assisted Colectomy with a Pfannenstiel Incision Reduces the Incisional Hernia Incidence.

Objectives: The present study examined the incidence of incisional hernia by comparing patients from whom a specimen was extracted either through a Pfannenstiel incision (PI) with an intracorporeal anastomosis or via a midline incision (MI) with an extracorporeal anastomosis. Methods: The records of 370 consecutive patients who underwent a laparoscopic or robotically-assisted colectomy were retrospectively analyzed. Regardless of the clinical symptoms, incisional hernia was objectively diagnosed based on abdominal computed tomography findings. The surgical outcomes and incisional hernia incidence were retrospectively compared between the groups. Propensity score matching (PSM) was used to balance background differences between the groups. Results: Eighty-seven and 283 patients were in the PI group and MI group, respectively. After PSM, 71 patients were selected from each group. The median observation time was 572 and 1110 days in the PI and MI group, respectively. The PI group had no incidence of incisional hernia whereas the MI group had a 14% incidence, demonstrating that the former had significantly fewer incisional hernias (p=0.0014). The median interval from surgery to incisional hernia development was 295 days. The PI with an intracorporeal anastomosis was not associated with an increased complication rate. Conclusions: The PI was preferable for intraoperative specimen extraction owing to the low, associated incidence of incisional hernia.

Genetic Testing of Japanese Patients with Serrated Polyposis Syndrome: A Multicentric Study.

Objectives: Serrated polyposis syndrome (SPS) is a rare condition associated with an increased risk of colorectal cancer. However, the genetic basis of SPS in Japanese patients remains unclear. The present study therefore aimed to address this omission by identifying candidate causative genes of SPS in Japanese patients. Methods: The present study performed next-generation sequencing using a multigene panel to identify the causative genes in SPS. Whenever a candidate gene was detected, whole exome sequencing of the tumor tissue was performed. Results: An analysis of 11 patients with SPS identified a germline pathogenic variant of BUB1 (c.1543G>T/p.Gly515Ter) in a 47-year-old, female patient with transverse colon cancer with more than 50 serrated polyps. She had no history of smoking. None of the canonical, causative genes in common colorectal cancer, such as APC, KRAS and TP53, were detected in her lesion. Most of the somatic variants detected in the cancer were transition substitutions (C>T). Conclusions: BUB1 was identified as a candidate causative gene in SPS in a non-smoker with the disease. These findings will hopefully contribute to understanding the genetic basis of SPS.

Real-world outcomes of FOLFOXIRI plus bevacizumab in patients with metastatic colorectal cancer: the JSCCR-TRIPON study.

BACKGROUND: FOLFOXIRI plus bevacizumab is a standard first-line chemotherapy for patients with metastatic colorectal cancer (mCRC). However, due to the severe toxicities, this regimen is not widely used. There is limited data on the real-world efficacy and safety. METHODS: We conducted a retrospective analysis of clinical data from mCRC patients who received FOLFOXIRI plus bevacizumab as first-line chemotherapy at 31 institutions. The initial dose was standardized according to the TRIBE regimen. Induction therapy was defined as a combination of oxaliplatin, irinotecan, and fluorouracil. RESULTS: Out of 104 patients who met the criteria, the median age was 58 years (range, 16-72). 81% of patients had an eastern cooperative oncology group performance status (PS) of 0. An initial dose reduction was observed in 63% of patients. The median number of preplanned induction therapy cycles was 12 (range, 4-12). The completion of scheduled induction therapy cycles was observed in 45% of patients, with treatment-related toxicities being the main reason for discontinuation (63%). The median progression-free survival and overall survival were 12.8 months (95% CI, 10.6-15.0) and 27.9 months (95% CI 21.6-34.2), respectively. The objective response rate and disease control rate were 63.7% and 98.9%, respectively. The R0 resection rate was 21.2%. The main grade 3 or higher toxicities were neutropenia (51%), febrile neutropenia (10%), and nausea/vomiting (5%). No treatment-related deaths were observed. CONCLUSION: In a real-world clinical setting, FOLFOXIRI plus bevacizumab demonstrated efficacy and safety comparable to previous clinical trials.

Predictive modeling for the germline pathogenic variant of the APC gene in patients with adenomatous polyposis: proposing a new APC score.

BACKGROUND: The precise diagnosis and medical management of patients with suspected familial adenomatous polyposis should be based on genetic testing, which may not always be available. Therefore, establishing a new model for predicting the likelihood of a germline pathogenic variant (GPV) of APC based on its clinical manifestations could prove to be useful in clinical practice. METHODS: The presence of GPVs of APC gene was investigated in 162 patients with adenomatous polyposis (≥ 10 polyps) using a multigene panel or single-gene testing. To generate a predictive model for GPV of the APC gene, a logistic regression analysis was performed using the clinicopathological variables available at the time of the diagnosis of adenomatous polyposis. RESULTS: Ninety (55.6%) patients had GPV of the APC gene. According to a multivariate logistic regression analysis, age < 40 years, polyps ≥ 100, fundic gland polyposis, and a family history of colorectal polyposis were found to be independent predictors of the GPV of APC and were used to establish a formula for predicting the GPV of APC using the four predictors. The prediction model had an area under the curve of 0.91 (0.86-0.96) according to a receiver operating characteristic analysis. CONCLUSION: The model for predicting the GPV of APC will help patients with adenomatous polyposis and physicians make decisions about genetic testing.

Evaluation of two-stage hepatectomy using portal vein embolization for colorectal liver metastasis: a retrospective nationwide cohort survey in Japan.

INTRODUCTION: Two-stage hepatectomy (TSH) enables patients to undergo surgery for colorectal liver metastasis (CRLM) which one-stage hepatectomy cannot remove. Although the outcome of TSH has been reported, there is no original report from Japan. The aim of this retrospective study was to evaluate the outcome of TSH in Japanese patients with CRLM. METHODS: We conducted a retrospective cohort study using the nationwide database that included clinical information of 12,519 patients treated with CRLM between 2005 and 2017 in Japan. The primary outcome measure was overall survival. The second outcome measure was progression-free survival. Fisher's exact test, chi-squared test and Mann-Whitney U test were conducted to examine an intergroup difference. Univariate and multivariate analyses were performed using Cox regression model. Survival analysis was performed by Kaplan-Meier method and log-rank test. RESULTS: Of the database, 53 patients undergoing TSH using portal vein embolization (PVE) were identified and analyzed. Their morbidity and in-hospital mortality rate at the second hepatectomy were 26.4% and 0.0%. The mean observation period was 21.8 months. The estimated 1-, 3- and 5-year overall survival rate were 92.5%, 70.8% and 34.7%. Multivariate analyses showed that more than 10 liver nodules significantly increased the mortality risk by 4.2-fold (95%CI 1.224-14.99, P= 0.023). Survival analysis revealed that repeat hepatectomy for disease progression after TSH was superior to chemotherapy in overall survival (mean: 49.6 vs. 18.7, months, P= 0.004). CONCLUSION: In the Japanese cohort, TSH was confirmed to be a safety procedure with acceptable survival outcome. More than 10 liver nodules may be a predictor for unfavorable outcome of patients with CRLM undergoing TSH. Furthermore, repeat hepatectomy can be a salvage treatment for resectable intrahepatic recurrence after TSH.

Colorectal cancer and advanced adenoma characteristics according to causative mismatch repair gene variant in Japanese colorectal surveillance for Lynch syndrome.

BACKGROUND: The optimal interval of colonoscopy (CS) surveillance in cases with Lynch syndrome (LS), and stratification according to the causative mismatch repair gene mutation, has received much attention. To verify a feasible and effective CS surveillance strategy, we investigated the colorectal cancer (CRC) incidence at different intervals and the characteristics of precancerous colorectal lesions of LS cases. METHODS: This retrospective multicenter study was conducted in Japan. CRCs and advanced adenomas (AAs) in 316 LS cases with germline pathogenic variants (path_) were analyzed according to the data of 1,756 registered CS. RESULTS: The mean time interval for advanced CRCs (ACs) detected via CS surveillance was 28.7 months (95% confidence interval: 13.8-43.5). The rate of AC detection within (2.1%) and beyond 2 years (8.7%) differed significantly (p = 0.0003). AAs accounted for 43%, 46%, and 41% of lesions < 10 mm in size in the MLH1-, MSH2-, and MSH6-groups, respectively. The lifetime incidence of metachronous CRCs requiring intestinal resection for path_MLH1, path_MSH2, and path_MSH6 cases was 34%, 23%, and 14% in these cases, respectively. The cumulative CRC incidence showed a trend towards a 10-year delay for path_MSH6 cases as compared with that for path_MLH1 and path_MSH2 cases. CONCLUSIONS: In cases with path_MLH1, path_MSH2, and path_MSH6, maintaining an appropriate CS surveillance interval of within 2 years is advisable to detect of the colorectal lesion amenable to endoscopic treatment. path_MSH6 cases could be stratified with path_MLH1 and MSH2 cases in terms of risk of metachronous CRC and age of onset.

Genomic landscape of comprehensive genomic profiling in patients with malignant solid tumors in Japan.

BACKGROUND: Comprehensive genomic profiling (CGP) can aid the discovery of clinically useful, candidate antitumor agents; however, the variant annotations sometimes differ among the various types of CGP tests as well as the public database. The aim of this study is to clarify the genomic landscape of evaluating detected variants in patients with a malignant solid tumor. METHODS: The present, cross-sectional study used data from 57,084 patients with a malignant solid tumor who underwent CGP at the Center for Cancer Genomics and Advanced Therapeutics (C-CAT) between June 1, 2019 and August 18, 2023. The pathogenicity of the variants was annotated using public databases. RESULTS: As a result of re-annotation of the detected variants, 20.1% were pathogenic and 1.4% were benign. The mean number of pathogenic variants was 4.30 (95% confidence interval: 4.27-4.32) per patient. Of the entire cohort, 5.7% had no pathogenic variant. The co-occurrence of the genes depended on the tumor type. Germline findings were detected in 6.2%, 8.8%, and 15.8% of the patients using a tumor/normal panel, tumor-only panel, and liquid panel, respectively, with the most common gene being BRCA2 followed by TP53 and BRCA1. CONCLUSIONS: The detected variants should be re-annotated because several benign variants or variants of unknown significance were included in the CGP, and the genomic landscape derived from these results will help researchers and physicians interpret the results of CGP tests. The method of extracting presumptive, germline, pathogenic variants from patients using a tumor-only panel or circulating tumor DNA panel requires improvement.

Recurrence of rectal cancer on the pelvic sidewall after lateral lymph node dissection.

PURPOSE: Although lateral lymph node dissection has been performed to prevent lateral pelvic recurrence in locally advanced lower rectal cancer, the incidence of lateral pelvic recurrence after this procedure has not been investigated. Therefore, this study aimed to investigate the long-term outcomes of patients who underwent lateral pelvic lymph node dissection, with a particular focus on recurrence patterns. METHODS: This was a retrospective study conducted at a single high-volume cancer center in Japan. A total of 493 consecutive patients with stage II-III rectal cancer who underwent lateral lymph node dissection between January 2005 and August 2022 were included. The primary outcome measures included patterns of recurrence, overall survival, and relapse-free survival. Patterns of recurrence were categorized as lateral or central pelvic. RESULTS: Among patients who underwent lateral lymph node dissection, 18.1% had pathologically positive lateral lymph node metastasis. Lateral pelvic recurrence occurred in 5.5% of patients after surgery. Multivariate analysis identified age > 75 years, lateral lymph node metastasis, and adjuvant chemotherapy as independent risk factors for lateral pelvic recurrence. Evaluation of the recurrence rate by dissection area revealed approximately 1% of recurrences in each area after dissection. CONCLUSION: We demonstrated the prognostic outcome and limitations of lateral lymph node dissection for patients with advanced lower rectal cancer, focusing on the incidence of recurrence in the lateral area after the dissection. Our study emphasizes the clinical importance of lateral lymph node dissection, which is an essential technique that surgeons should acquire.

Marital status after colorectal surgery in familial adenomatous polyposis: a nationwide multicenter study in Japan.

BACKGROUND: Patients with familial adenomatous polyposis (FAP) experience psychological and social challenges concerning future events such as marriage and childbirth alongside the medical risks of colorectal cancer (CRC) and FAP-related disease. We retrospectively investigated the rate of marriage and childbirth postoperatively in Japanese patients with FAP. METHODS: We included 161 patients who had colorectal surgery and reported marital status from a national survey of 35 Japanese institutions. Participants were classified according to marital status: married before colectomy (80 patients), married after colectomy (13 patients), and unmarried (68 patients). RESULTS: The marriage rate for all 161 patients (57.8%, standardized ratio 0.95, 95% confidence interval [CI] 0.76-1.14) was comparable to that in the general Japanese population (57.1%). The marriage rate among the 81 patients who were unmarried before colectomy was low (16.0%); however, the standardized marital ratio (0.75, 95% CI 0.34-1.15) was not significantly lower than that of the general population. In multivariable logistic regression, younger age (born after 1980, odds ratio [OR] 0.12, p < 0.001) and genetic testing (OR 4.06, p = 0.001) were associated with postoperative marriage. Seventy-one percent of patients with FAP who married after colectomy became pregnant and achieved delivery. CONCLUSIONS: The marriage rate of patients with FAP was comparable to that of the general population whereas the rate after colectomy was low among patients with FAP. However, in patients with FAP, colorectal surgery itself may not lead to negative consequences in terms of fecundity.

Modified neoadjuvant rectal score as a novel prognostic model for rectal cancer patients who underwent chemoradiotherapy.

BACKGROUND: The neoadjuvant rectal score (NAR score) has recently been proposed as a better prognostic model than the conventional TNM classification for rectal cancer patients that have undergone neoadjuvant chemoradiotherapy. We recently developed an apoptosis-detection technique for assessing the viability of residual tumors in resected specimens after chemoradiotherapy. This study aimed to establish an improved prognostic classification by combining the NAR score and the assessment of the apoptosis of residual cancer cells. METHODS: We retrospectively enrolled 319 rectal cancer patients who underwent chemoradiotherapy followed by radical surgery. The recurrence-free survival and overall survival of the four models were compared: TNM stage, NAR score, modified TNM stage by re-staging according to cancer cell viability, and modified NAR score also by re-staging. RESULTS: Downstaging of the ypT stage was observed in 15.5% of cases, whereas only 4.5% showed downstaging of ypN stage. C-index was highest for the modified NAR score (0.715), followed by the modified TNM, TNM, and NAR score. Similarly, Akaike's information criterion was smallest in the modified NAR score (926.2), followed by modified TNM, TNM, and NAR score, suggesting that the modified NAR score was the best among these four models. The overall survival results were similar: C-index was the highest (0.767) and Akaike's information criterion was the smallest (383.9) for the modified NAR score among the four models tested. CONCLUSION: We established a novel prognostic model, for rectal cancer patients that have undergone neoadjuvant chemoradiotherapy, using a combination of apoptosis-detecting immunohistochemistry and neoadjuvant rectal scores.

Clinicopathological characteristics of Lynch-like syndrome.

BACKGROUND: Lynch-like syndrome (LLS) has recently been proposed as a third type of microsatellite instability (MSI) tumor after Lynch syndrome (LS) and sporadic MSI colorectal cancer (CRC) without either a germline variant of mismatch repair (MMR) genes or hypermethylation of the MLH1 gene. The present study aimed to clarify and compare the clinicopathological characteristics of LLS with those of the other MSI CRC subtypes. METHODS: In total, 2634 consecutive patients with CRC who underwent surgical resection and subsequently received universal tumor screening (UTS), including MSI analysis were enrolled between January 2008 and November 2019. Genetic testing was performed in patients suspected of having Lynch syndrome. RESULTS: UTS of the cohort found 146 patients with MSI CRC (5.5%). Of these, excluding sporadic MSI CRC, 30 (1.1%) had a diagnosis of LS, and 19 (0.7%) had no germline pathogenic variants of the MMR gene. The CRC type in the latter group was identified as LLS. LLS occurred significantly more often in young patients, was left-sided, involved a KRAS variant and BRAF wild-type, and had a higher concordance rate with the Revised Bethesda Guidelines than sporadic MSI CRC. No significant differences were observed in terms of the clinicopathological factors between LLS and LS-associated MSI CRC; however, LLS had a lower frequency of LS-related neoplasms compared with LS. CONCLUSIONS: Distinguishing clinically between LS and LLS was challenging, but the incidence of neoplasms was higher in LS than in LLS, suggesting the need for different screening and surveillance methods for the two subtypes.

Incidence and molecular characteristics of deficient mismatch repair conditions across nine different tumors and identification of germline variants involved in Lynch-like syndrome.

BACKGROUND: Based on molecular characteristics, deficient DNA mismatch repair (dMMR) solid tumors are largely divided into three categories: somatically MLH1-hypermethylated tumors, Lynch syndrome (LS)-associated tumors, and Lynch-like syndrome (LLS)-associated tumors. The incidence of each of these conditions and the corresponding pathogenic genes related to LLS remain elusive. METHODS: We identified dMMR tumors in 3609 tumors from 9 different solid organs, including colorectal cancer, gastric cancer, small-bowel cancer, endometrial cancer, ovarian cancer, upper urinary tract cancer, urinary bladder cancer, prostate cancer, and sebaceous tumor, and comprehensively summarized the characterization of dMMR tumors. Characterization of dMMR tumors were performed as loss of at least one of MMR proteins (MLH1, MSH2, MSH6, and PMS2), by immunohistochemistry, followed by MLH1 promotor methylation analysis and genetic testing for MMR genes where appropriate. Somatic variant analysis of MMR genes and whole exome sequencing (WES) were performed in patients with LLS. RESULTS: In total, the incidence of dMMR tumors was 5.9% (24/3609). The incidence of dMMR tumors and the proportion of the three categorized dMMR tumors varied considerably with different tumor types. One to three likely pathogenic/pathogenic somatic MMR gene variants were detected in 15 out of the 16 available LLS tumors. One patient each from 12 patients who gave consent to WES demonstrated non-MMR germline variants affect function (POLQ or BRCA1). CONCLUSIONS: Our data regarding the LS to LLS ratio would be useful for genetic counseling in patients who are suspected to have LS, though the genetic backgrounds for the pathogenesis of LLS need further investigation.

Hazard function analysis of prognosis after recurrent colorectal cancer.

BACKGROUND AND OBJECTIVES: Mean survival time (MST) is used as the indicator of prognosis in patients with a colorectal cancer (CRC) recurrence. The present study aimed to visualize the changes in death risk after a CRC recurrence using hazard function analysis (HFA) to provide an alternative prognostic indicator to MST. METHODS: The medical records of 725 consecutive patients with a recurrence following R0 radical surgery for CRC were retrospectively reviewed. RESULTS: The five-year, post-recurrence survival rate was 37.8%, and the MST was 3.5 years while the risk of death peaked at 2.9 years post-recurrence. Seven variables were found to predict short-term survival, including the number of metastatic organs ≥ 2, non-surgical treatment for the recurrence, and a short interval before recurrence. In patients with a recurrence in one organ, the MST was four years, the peak time of death predicted by HFA was 2.9 years, and the five-year survival rate was 45.8%. In patients with a surgical resection of the recurrence, the MST was 8 years, the peak time of death was 3.3 years, and the five-year survival rate was 62%. CONCLUSIONS: The present study established a novel method of assessing changes in mortality risk over time using HFA in patients with a CRC recurrence.

Risk of metachronous colorectal cancer after surgical resection of index rectal cancer in Lynch syndrome: a multicenter retrospective study in Japan.

PURPOSE: This study evaluated the risk of metachronous colorectal cancer (CRC) after resection of index (first) rectal cancer in patients with Lynch syndrome (LS). METHODS: Clinicopathological data of patients with genetically proven LS were retrospectively analyzed in this multicenter Japanese study. The cumulative incidence of metachronous CRC and the overall survival were compared between patients with index rectal cancer (rectal group) and those with index colon cancer (colon group). RESULTS: The median age at index CRC surgery was lower in the rectal group than in the colon group (37 vs. 46 years old, P = 0.01). The cumulative 5-, 10-, and 20-year incidences of metachronous CRC were 3.5%, 13.9%, and 21.1%, respectively, in the rectal cancer group and 14.9%, 22.0%, and 57.9%, respectively, in the colon cancer group (P = 0.02). The overall survival curves were not significantly different between two groups (P = 0.23). CONCLUSION: This is the first report from an East Asian country to report the risk of metachronous CRC after resection of index rectal cancer in patients with LS. Despite this study having several limitations, we cannot recommend extended resection, such as total proctocolectomy, for index rectal cancer as a standard surgical treatment in patients with LS.

Risk of gastric adenoma and adenocarcinoma in patients with familial adenomatous polyposis in Japan: a nationwide multicenter study.

BACKGROUND: Patients with familial adenomatous polyposis (FAP) have an increased risk of developing gastric neoplasms. However, the clinical course of FAP with these gastric lesions has not yet been fully clarified. The present study aimed to clarify the changes in the incidence risk of developing gastric adenoma or gastric cancer during the lifespan of patients with FAP. METHODS: Four hundred forty-three patients with data regarding gastric adenoma and gastric cancer retrospectively registered in a nationwide Japanese multicenter study were enrolled. The cumulative incidences and hazard rates (HRs) of gastric neoplasms were evaluated. RESULTS: The cumulative incidence rates in 50-year-old patients with FAP were 22.8% for gastric adenoma and 7.6% for gastric cancer, respectively. No significant association was found between gastric neoplasms and the colonic phenotype. The peak age for the HR of gastric adenoma was 65 years, with the highest HR (0.043). Regarding the incidence of gastric cancer, the HR increased moderately up to the age of 40 years, but the increase accelerated from the age of 50 years (HR = 0.0067). CONCLUSION: Careful surveillance of the upper gastrointestinal tract in elderly patients with FAP, such as shortening the interval of follow-up according to age, may be helpful for early diagnosis of gastric cancer.

Clinical features and distribution of the APC variant in duodenal and ampullary polyps in patients with familial adenomatous polyposis: a multicenter retrospective cohort study in Japan.

BACKGROUND: Management of duodenal or ampullary adenomas in patients with familial adenomatous polyposis (FAP) is a major challenge for clinicians. Insufficient data are available to evaluate the clinical manifestations and distribution of adenomatous polyposis coli (APC) variants in these patients. METHODS: We enrolled 451 patients with data regarding duodenal or ampullary polyps from 632 patients with FAP retrospectively registered in a nationwide Japanese multicenter study. Clinicopathological features and distribution of APC variants were compared between patients with and without duodenal or ampullary polyps. RESULTS: Duodenal and ampullary polyps were found in 59% and 18% of patients with FAP, respectively. The incidence of duodenal cancer was 4.7% in patients with duodenal polyps, and that of ampullary cancer was 18% in patients with ampullary polyps. Duodenal polyps were significantly associated with the presence of ampullary polyps and jejunal/ileal polyps. Duodenal polyps progressed in 35% of patients with a median follow-up of 776 days, mostly in those with early Spigelman stage lesions. Ampullary polyps progressed in 50% of patients with a follow-up of 1484 days. However, only one patient developed a malignancy. The proportion of patients with duodenal polyps was significantly higher among those with intermediate- or profuse-type APC variants than attenuated-type APC variants. The presence of duodenal polyps was significantly associated with ampullary and jejunal/ileal polyps in patients with intermediate- or profuse-type APC variants. CONCLUSIONS: Periodic endoscopic surveillance of the papilla of Vater and small intestine should be planned for patients with FAP with duodenal polyps.

Usefulness of genotyping APC gene for individualizing management of patients with familial adenomatous polyposis.

BACKGROUND: Colorectal polyp burden is crucial for the management of patients with familial adenomatous polyposis (FAP). However, accurate evaluation of polyp burden is difficult to standardize. This study aimed to examine the possible utility of genotype-oriented management of colorectal neoplasms in patients with FAP. METHODS: Clinicopathological data from genetically proven patients with FAP was analyzed using the database of a nationwide retrospective Japanese multicenter study. The cumulative incidence of CRC was evaluated between different genotype groups. Genotype-1 were defined as germline variants on attenuated FAP-associated regions (codons 1-177, alternative splice site of exon 10 (codon 312), 1581-2843) and Genotype-2 as the other variants. Weibull and Joinpoint analyses were performed to determine the annual percentage changes in CRC risk. RESULTS: Overall, 69 men and 102 women were included. Forty-eight patients underwent colorectal resection for the first CRC, and five patients underwent resection for first cancer in the remnant anorectal segment after prophylactic surgery. The 70-year cumulative incidence of CRC in all patients was 59.3%. Patients with Genotype-1 (n = 23) demonstrated a lower risk of CRC stages II-IV than those with Genotype-2 (n = 148, P = 0.04). The risk of stage II-IV CRC was estimated to increase markedly at the age of 49 years in the Genotype-1 patients and 34 years in the Genotype-2 patients, respectively. CONCLUSIONS: Different interventional strategies based on genotypes may be proposed for the clinical management of patients with FAP. This policy needs to be validated in further prospective studies focusing on long-term endoscopic intervention and optimal age at prophylactic (procto)colectomy.

Risk of metachronous colorectal cancer after colectomy for first colon cancer in Lynch syndrome: multicenter retrospective study in Japan.

BACKGROUND: We evaluated the risk of metachronous colorectal cancer (mCRC) and explored the optimal extent of colectomy in patients with Lynch syndrome (LS) and first colon cancer (fCC) in Japan, where the extent of colectomy for colon cancer (CC) is shorter than that in Western countries. METHODS: The clinicopathologic and survival data of patients with LS who developed CC were collected from a nationwide database and analyzed retrospectively. The cumulative incidence of mCRC after actual segmental colectomy was compared with that of mCRC when more extensive colectomy was assumed. RESULTS: There were 142 eligible patients (65 female). The median age at fCC surgery was 46.5 (range: 14-80) years. The cumulative incidence of 5-, 10-, and 20-year mCRC rate was 13.4%, 20.8%, and 53.6%, respectively. The incidence was higher in the left-sided group (splenic flexure to rectosigmoid colon, n = 54) than in the right-sided group (cecum to transvers colon, n = 88) (66.3% vs. 45.3% in 20 years, P < 0.01). Assuming that all patients would have undergone hemicolectomy or total colectomy, the estimated mCRC risk was 41.5% and 9.4% (P < 0.01, vs. actual procedures), respectively. The 20-year overall survival rate of all the patients was 83.3% without difference by fCC sidedness (P = 0.38). CONCLUSIONS: To reduce the incidence of mCRC, patients with genetically diagnosed LS and fCC, preferentially located in the left-sided colon, may need to undergo more extended colectomy than that usually performed in Japan. However, such extended colectomy should be counterbalanced with favorable overall survival and actual risk of mCRC development.

PTPN11 variant may be a prognostic indicator of IDH-wildtype glioblastoma in a comprehensive genomic profiling cohort.

PURPOSE: Glioblastoma (GBM) is the most common type of primary malignant brain tumor and has a poor prognosis. Identifying novel targets and stratification strategies is urgently needed to improve patient survival. The present study aimed to identify clinically relevant genomic alterations in IDH-wildtype GBM using data from comprehensive genomic profiling (CGP) assays performed nationwide in Japan. METHODS: The CGP assay results of 392 IDH-wildtype GBM cases performed between October 2019 and February 2023 obtained from the Center for Cancer Genomics and Advanced Therapeutics were retrospectively analyzed. RESULTS: The median patient age was 52.5 years, and 207 patients (53%) were male. In the 286 patients for whom survival information was available, a protein-tyrosine phosphatase non-receptor type 11 (PTPN11) variant detected in 20 patients (6.8%) was extracted as the gene associated with significantly shorter overall survival (p = 0.002). Multivariate analysis demonstrated that the PTPN11 variant and poor performance status were independent prognostic indicators. In contrast, no prognostic impact was observed in the cohort in The Cancer Genome Atlas data. The discrepancy in the prognostic impact of the PTPN11 variant from these two pools might have resulted from differences in the biases affecting the survival of patients who underwent a CGP assay, including left-truncation and right-censored bias. However, survival simulation done to adjust for these biases showed that the prognostic impact of the PTPN11 variant was also significant. CONCLUSIONS: The PTPN11 variant was a negative prognostic indicator of IDH-wildtype GBM in the patient cohort with the CGP assay.