Peritoneal lavage cytology in patients with curative resection for stage II and III colorectal cancer: A multi-institutional prospective study.

Aim: To clarify the usefulness of intraoperative lavage cytology in patients undergoing curative resection for pStage II-III colorectal cancer in a prospective multicenter study. Methods: Patients preoperatively diagnosed with stage II-III colorectal cancer between 2013 and 2017 from 20 hospitals were enrolled. Lavage cytology was performed twice during the surgery. The primary endpoint was the effect of lavage cytology on the 5-year relapse-free survival (RFS) in patients with pStage II-III colorectal cancer. The secondary endpoint was the effect of lavage cytology on the 5-year overall survival (OS) and peritoneal recurrence. Results: A total of 1378 patients were eligible for analysis. The number of patients with pStage II-III colorectal cancer was 670 and 708, respectively. Fifty-four patients (3.9%) had positive cytological results. In pStage II patients, the 5-year RFS rates with positive and negative cytology were 61.1% and 81.6%, respectively (p = 0.023). The 5-year OS rates were 67.1% and 91.7%, respectively (p = 0.0083). However, there was no difference in RFS or OS between pStage III patients with positive and negative cytology results. The peritoneal recurrence rates were 11.8% and 1.5% in pStage II patients with positive and negative cytology results, respectively (p = 0.032). These rates were 10.5% and 2.5% in patients with stage III disease, respectively (p = 0.022). Conclusion: Stage II colorectal cancer patients with negative cytology had better outcomes than those with positive cytology. Peritoneal lavage cytology is useful for predicting peritoneal recurrence after curative resection of stage II-III colorectal cancer.

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.

A proposed new Japanese classification of synchronous peritoneal metastases from colorectal cancer: A multi-institutional, prospective, observational study conducted by the Japanese Society for Cancer of the Colon and Rectum.

Aim: To establish a new Japanese classification of synchronous peritoneal metastases from colorectal cancer. Methods: This multi-institutional, prospective, observational study enrolled patients who underwent surgery for colorectal cancer with synchronous peritoneal metastases. Overall survival rates were compared according to the various models using objective indicators. Each model was evaluated by Akaike's information criterion (AIC). The region of peritoneal metastases was evaluated by the peritoneal cancer index (PCI). Results: Between October 2012 and December 2016, 150 patients were enrolled. The AIC of the present Japanese classification was 1020.7. P1 metastasis was defined as confined to two regions. The minimum AIC was obtained with the cutoff number of 10 or less for P2 metastasis and 11 or more for P3 metastasis. As for size, the best discrimination ability between P2 and P3 metastasis was obtained with a cutoff value of 3 cm. The AIC of the proposed classification was 1014.7. The classification was as follows: P0, no peritoneal metastases; P1, metastases localized to adjacent peritoneum (within two regions of PCI); P2, metastases to distant peritoneum, number ≤10 and size ≤3 cm; P3, metastases to distant peritoneum, number ≥11 or size >3 cm; P3a, metastases to distant peritoneum, number ≥11 and size ≤3 cm, or number ≤10 and size >3 cm; P3b, metastases to distant peritoneum, number ≥11 and size >3 cm. Conclusion: This objective classification could improve the ability to discriminate prognosis in patients with synchronous peritoneal metastases from colorectal cancer.

Comprehensive data of 4502 patients newly diagnosed with colorectal liver metastasis between 2015 and 2017, and prognostic data of 2427 patients newly diagnosed with colorectal liver metastasis in 2013 and 2014: Third report of a nationwide survey in Japan.

To improve treatment outcomes in patients with colorectal liver metastasis (CRLM), the Joint Committee for Nationwide Survey on CRLM was established by the Japanese Society for Cancer of the Colon and Rectum and the Japanese Society of Hepato-Biliary-Pancreatic Surgery. The aim of the study was to evaluate transition in the characteristics and treatment strategy in CRLM patients and analyze prognostic factors using large-scale data. The present study summarizes the data of patients newly diagnosed between 2015 and 2017 and presents prognostic data of patients newly diagnosed in 2013 and 2014. Survival curves were generated by the Kaplan-Meier method and compared by log-rank test. Multivariate analyses were carried out using Cox proportional hazard modeling. The data of 4502 patients newly diagnosed with CRLM between 2015 and 2017 and the prognostic data of 2427 patients diagnosed in 2013 and 2014 are included. Regarding the 2013 and 2014 prognostic data, the 5-year overall survival (OS) rates of patients who underwent hepatectomy alone was 59.8%. Multivariate analyses identified age at diagnosis of CRLM ≥70 years, concomitant extrahepatic metastasis at diagnosis of CRLM, tumor depth of primary lesion ≥subserosa/pericolic or perirectal tissue, mutant KRAS status, number of CRLM ≥5, maximum diameter of CRLM >5 cm, and surgical curability R1/R2 as independent predictors of OS. Analysis of the latest nationwide database of patients diagnosed with CRLM revealed changes in patients and oncological characteristics, a transition in treatment strategy, and different independent prognosticators to those reported previously.

Validation study of the JSHBPS nomogram for patients with colorectal liver metastases who underwent hepatic resection in the recent era - a nationwide survey in Japan.

BACKGROUND: The Japanese Society of Hepato-Biliary-Pancreatic Surgery (JSHBPS) nomogram was developed to predict disease-free survival in patients with colorectal liver metastases (CRLM) undergoing upfront hepatectomy. However, the utility of the nomogram in patients with resected CRLM remains unknown in the current situation in which treatment strategies are changing with advances in drugs. METHODS: Patients in the initial nomogram cohort (n = 727) and validation cohort (n = 2225) were divided into the upfront hepatectomy and preoperative chemotherapy groups. The nomogram was validated by measuring calibration and discrimination in the two cohorts. Calibration curves were plotted, and survival probabilities were compared. Finally, to quantify the discrimination power, we estimated the concordance index (C-index). RESULTS: In the upfront hepatectomy group, the C-index was 0.63, the suitable cutoff value of the Beppu score was 7, and adjuvant chemotherapy was significantly effective limited to high-risk patients (Beppu score ≥7). The C-index was 0.56 in the preoperative chemotherapy group. CONCLUSIONS: The JSHBPS nomogram remains beneficial for patients undergoing upfront hepatectomy in the recent era but is less effective for patients undergoing hepatectomy after chemotherapy. Patients with a Beppu score ≥7 showed high-risk recurrence, and adjuvant chemotherapy should be recommended for these patients.

Factors Affecting Positive Peritoneal Lavage Cytology in Patients with Stage II and III Colorectal Cancer with R0 Resection: A Multi-institutional, Prospective Study.

OBJECTIVES: This study aimed to explore the risk factors associated with cancer cell exfoliation in Stage II and III colorectal cancer (CRC). METHODS: This multicenter, prospective, observational study targeted 1,698 patients with cStage II and III CRC who underwent R0 resection between 2013 and 2017. Clinicopathological variables were analyzed for correlations with positive peritoneal lavage cytology (PLC). RESULTS: The positive PLC rate was 2.7% (46/1,694 cases) at laparotomy and 1.6% (25/1,590 cases) after tumor resection. Logistic regression analyses identified that undifferentiated histologies diagnosed by preoperative biopsy specimen, cT4, and pN+ were independent factors that affected the positive PLC at laparotomy. The positive PLC rate at laparotomy was 4.5% (33/736 cases) among the patients with undifferentiated histology and/or cT4. Logistic regression analyses revealed that the presence of ascites and undifferentiated histology by biopsy independently affected positive PLC after tumor resection. CONCLUSIONS: The undifferentiated histology and/or T4 indicated by preoperative diagnosis were identified as factors affecting PLC at laparotomy. Furthermore, ascites and preoperative histological type were identified as factors affecting positive PLC after tumor resection. As factors affecting positive PLC, these preoperative findings were found to be equivalent to pathological findings.

Impact of R0 resection for synchronous peritoneal metastasis from colorectal cancer: A propensity score-matched analysis of a multi-institutional database.

AIM: To investigate the usefulness of resection for synchronous peritoneal metastasis from colorectal cancer. METHODS: The patients who underwent surgery for stage IV colorectal cancer at 16 hospitals between 1991 and 2007 were enrolled in this study. The overall survival rates of patients with synchronous peritoneal metastasis from colorectal cancer with and without R0 resection were compared using a propensity score-matched analysis. RESULTS: Among the 3965 patients with stage IV colorectal cancer, 1169 had synchronous peritoneal metastasis (28.5%). No patients received hyperthermic intraperitoneal chemotherapy (HIPEC) in this study. Among the 1169 patients, 783 had enough clinicopathologic information and went through further analysis. Out of 783 patients, 204 underwent R0 resection. A multivariate analysis revealed that severity of peritoneal metastasis according to the Japanese classification (P < .0001) and distant metastases (P < .0001) were independently associated with non-R0 resection. In a propensity score-matched analysis, 118 patients who underwent R0 resection were matched with 118 patients who did not undergo R0 resection. There was no significant difference in each parameter between patients with and without R0 resection. After matching, the overall survival in patients with R0 resection was better than that without R0 resection (median survival time: 28.8 months and 15.6 months, P < .0001). CONCLUSION: The overall survival of patients with R0 resection for synchronous peritoneal metastasis from colorectal cancer was better than that without R0 resection even without HIPEC.

Proposal of a novel H category-based classification of colorectal liver metastases based on a Japanese nationwide survey.

BACKGROUND: The conventional H category-based classification for colorectal liver metastases (CRLM) was created by equal weighting of tumor number and tumor size; however, our previous nomogram to predict postoperative disease-free survival demonstrated that CRLM ≥5 as a parameter provided 4.5 times greater impact compared with a largest CRLM size >5 cm. METHODS: A total of 3815 patients newly diagnosed with CRLM between 2005 and 2007, including 2220 resectable cases, were investigated. Six groups were created based on largest lesion size (≤ 5 vs >5 cm) and lesion number (1, 2-4, and ≥5). RESULTS: The novel (n) H1, nH2, and nH3 categories were defined as solitary lesions with a size ≤5 cm; lesions other than nH1 or nH3; and ≥5 lesions with any lesion size, respectively. In the resectable cohort, the 5-year cumulative overall survival rates were 64.0%, 53.5%, and 42.6% in the nH1, nH2, and nH3 groups, respectively (P < .001), and no significant differences were observed between the conventional H2 and H3 categories. In the overall cohort, the discrimination ability of the two classifications were comparable. CONCLUSION: The novel H category-based classification might be beneficial in predicting overall survival in patients with CRLM independent of their resectability.

Investigation of the Japanese Classification of Peritoneal Metastasis from Colorectal Cancer Referring to the Correlation with PCI.

OBJECTIVES: In Japan, there are three grades of peritoneal metastasis from colorectal cancer. The grade depends on the extent and number of lesions (P classification). The P classification is useful for its simplicity but lacks objectivity. On the other hand, the peritoneal cancer index (PCI) objectively indicates the peritoneal metastasis grade. However, the evaluation process is complicated clinically. In this study, we compared these two methods and investigated how to improve the P classification's objectivity by referring to PCI. METHODS: We investigated 150 cases of synchronous peritoneal metastasis from colorectal cancer. We inspected the correlation between the P classification and the PCI and pointed out the problems which prevented objective evaluation when using the P classification. We also estimated new criteria for extent and number in the P classification. RESULTS: We found the ideal definition for the best alignment between the P classification and the PCI was: ・P1 is metastases confined to one peritoneal region, ・P2 is 19 or fewer peritoneal metastases in two or more regions, and ・P3 is 20 or more metastases in two or more regions. This revision improved the P classification's objectivity and correlated with the PCI. CONCLUSIONS: Grading using the P classification was both imprecise and subjective. We propose a new standard value of extent and number in the P classification based on the PCI. This improvement would provide an objective, simple method of grading for peritoneal metastasis from colorectal cancer.

Long-term outcome of liver resection for colorectal metastases in the presence of extrahepatic disease: A multi-institutional Japanese study.

BACKGROUND/PURPOSE: The purpose of the present study was to assess long-term outcomes following liver resection for colorectal liver metastases (CRLM) with concurrent extrahepatic disease and to identify the preoperative prognostic factors for selection of operative candidates. METHODS: In this retrospective, multi-institutional study, 3820 patients diagnosed with CRLM during 2005-2007 were identified using nationwide survey data. Data of identified patients with concurrent extrahepatic lesions were analyzed to estimate the impact of liver resection on overall survival (OS) and to identify preoperative, prognostic indicators. RESULTS: Three- and 5-year OS rates after liver resection in 251 CRLM patients with extrahepatic disease (lung, n = 116; lymph node, n = 51; peritoneal, n = 37; multiple sites, n = 23) were 50.2% and 32.0%, respectively. Multivariate analysis revealed that a primary tumor in the right colon, lymph node metastasis from the primary tumor, serum carbohydrate antigen (CA) 19-9 level >37 UI/mL, the site of extrahepatic disease, and residual liver tumor after hepatectomy were associated with higher mortality. We proposed a preoperative risk scoring system based on these factors that adequately discriminated 5-year OS after liver resection in training and validation datasets. CONCLUSIONS: Performing R0 liver resection for colorectal liver metastases with treatable extrahepatic disease may prolong survival. Our proposed scoring system may help select appropriate candidates for liver resection.

Impact of adherence to board-certified surgeon systems and clinical practice guidelines on colon cancer surgical outcomes in Japan: A questionnaire survey of the National Clinical Database.

AIM: To investigate the effectiveness of the institutional medical structure and of the implemented clinical practice guidelines for improving colon cancer surgical outcomes. METHODS: We conducted a web-based questionnaire survey among departments registered at the National Clinical Database in Japan from October 2014 to January 2015 to assess the association between quality indicators (QIs), including structure and process indicators (clinical practice guideline adherence), and the risk-adjusted odds ratio for operative mortality (AOR) after right hemicolectomy for colorectal cancer during the study period. RESULTS: Among the 2064 departments registering at least one colorectal surgery during the study period, we obtained responses from 814 departments (39.4%). Our analysis on data from 22 816 patients with right hemicolectomy demonstrated that three structural QIs (certification of training hospitals by the Japanese Society of Gastroenterological Surgery and the presences of board-certified gastroenterological and colorectal surgeons) were associated with significantly lower AOR (P < .001, P = .02, and P = .05, respectively). The "performed at the doctor's discretion" answer was associated with poorer short-term outcomes in six process QIs than other answers. CONCLUSION: The board certification system for gastroenterological and colorectal surgeons and the adherence to the clinical guidelines improve the operative mortality after right hemicolectomy. It is desired to clarify the most suitable QIs to reduce the operative mortality after colorectal surgery.

Prognostic Impact of the Length of the Distal Resection Margin in Rectosigmoid Cancer: An Analysis of the JSCCR Database between 1995 and 2004.

OBJECTIVES: The necessary and sufficient length of the distal resection margin (l-DRM) for rectosigmoid cancer remains controversial. This study evaluated the validity of the 3-cm l-DRM rule for rectosigmoid cancer in the Japanese classification of colorectal cancer. METHODS: We retrospectively reviewed 1,443 patients with cT3 and cT4 rectosigmoid cancer who underwent R0 resection in Japanese institutions between 1995 and 2004. We identified the optimal cutoff point of the l-DRM affecting overall survival (OS) rate using a multivariate Cox regression analysis model. Using this cutoff point, the patients were divided into two groups after balancing the potential confounding factors of the l-DRM using propensity score matching, and the OS rates of the two groups were compared. RESULTS: A multivariate Cox regression analysis model revealed that the l-DRM of 4 cm was the best cutoff point with the greatest impact on OS rate (hazard ratio [HR], 1.37; 95% confidence interval [CI], 1.00-1.84; P = 0.0452) and with the lowest Akaike information criterion value. In the matched cohort study, the OS rate of patients who had l-DRM of 4 cm or more was significantly higher than that of patients who had l-DRM < 4 cm (n = 402; 5-year OS rates, 87.6% vs. 80.3%, respectively; HR, 1.60; 95% CI, 1.09-2.31; P = 0.0136). CONCLUSIONS: For cT3 and cT4 rectosigmoid cancer, l-DRM of 4 cm may be an appropriate landmark for a curative intent surgery, and we were unable to definitively confirm the validity of the Japanese 3-cm l-DRM rule.

Comprehensive data of 3525 patients newly diagnosed with colorectal liver metastasis between 2013 and 2014: 2nd report of a nationwide survey in Japan.

BACKGROUND: To collect large-scale data for further research to improve treatment outcomes in patients with colorectal liver metastasis (CRLM), the Joint Committee for Nationwide Survey on CRLM was established by the Japanese Society for Cancer of the Colon and Rectum and the Japanese society of Hepato-Biliary-Pancreatic Surgery. The joint committee was initiated to collect data since 2014 and has already reported data including the prognostic data of 3820 patients newly diagnosed with CRLM between 2005 and 2007. METHODS: The data of patients newly diagnosed with CRLM after 2013 are continuously being registered prospectively, and herein, we report the data of the patients newly diagnosed with CRLM in 2013 and 2014. RESULTS: The data of 3839 patients newly diagnosed with CRLM in 2013 and 2014 were registered from 156 departments (75%) of 152 institutions among 209 departments (from 201 institutions) that agreed to participate in this database system at its initiation. Finally, 3525 patients were enrolled in this study after a quality management process conducted by the joint committee. We report the comprehensive data obtained from 3525 patients, including clinicopathological findings, treatment strategies, and implementation status of chemotherapy. CONCLUSION: The joint committee will provide these raw data while updating prognostic data to researchers who will conduct meaningful studies that meet the aim of the joint committee.

S-1 and Oxaliplatin Versus Tegafur-uracil and Leucovorin as Postoperative Adjuvant Chemotherapy in Patients With High-risk Stage III Colon Cancer (ACTS-CC 02): A Randomized, Open-label, Multicenter, Phase III Superiority Trial.

BACKGROUND: The efficacy of S-1 plus oxaliplatin (SOX) as postoperative adjuvant chemotherapy for colon cancer has not been established. This randomized phase III study was designed to verify the superiority of SOX over tegafur-uracil and leucovorin (UFT/LV) in patients with high-risk stage III colon cancer (any T, N2, or positive nodes around the origin of the feeding arteries). PATIENTS AND METHODS: Patients who underwent curative resection for pathologically confirmed high-risk stage III colon cancer were randomly assigned to receive either UFT/LV (300 mg/m2 of UFT and 75 mg/day of LV on days 1-28, every 35 days, 5 cycles) or SOX (100 mg/m2 of oxaliplatin on day 1 and 80 mg/m2 of S-1 on days 1-14, every 21 days, 8 cycles). The primary endpoint was disease-free survival (DFS). RESULTS: A total of 478 patients in the UFT/LV group and 477 patients in the SOX group were included in the primary analysis. The 3-year DFS was 60.6% (95% confidence interval [CI], 56.0%-64.9%) in the UFT/LV group and 62.7% (95% CI, 58.1%-66.9%) in the SOX group. The stratified hazard ratio for DFS was 0.90 (95% CI, 0.74-1.09; stratified log-rank test, P = .2780). In the N2b subgroup, the 3-year DFS was 46.0% (95% CI, 37.5%-54.0%) in the UFT/LV group and 54.7% (95% CI, 45.7%-62.7%) in the SOX group (hazard ratio, 0.76; 95% CI, 0.55-1.05). CONCLUSION: As postoperative adjuvant chemotherapy, SOX was not superior to UFT/LV in terms of DFS in patients with high-risk stage III colon cancer.

Japanese Society for Cancer of the Colon and Rectum (JSCCR) guidelines 2019 for the treatment of colorectal cancer.

The number of deaths from colorectal cancer in Japan continues to increase. Colorectal cancer deaths exceeded 50,000 in 2016. In the 2019 edition, revision of all aspects of treatments was performed, with corrections and additions made based on knowledge acquired since the 2016 version (drug therapy) and the 2014 version (other treatments). The Japanese Society for Cancer of the Colon and Rectum guidelines 2019 for the treatment of colorectal cancer (JSCCR guidelines 2019) have been prepared to show standard treatment strategies for colorectal cancer, to eliminate disparities among institutions in terms of treatment, to eliminate unnecessary treatment and insufficient treatment and to deepen mutual understanding between healthcare professionals and patients by making these guidelines available to the general public. These guidelines have been prepared by consensuses reached by the JSCCR Guideline Committee, based on a careful review of the evidence retrieved by literature searches and in view of the medical health insurance system and actual clinical practice settings in Japan. Therefore, these guidelines can be used as a tool for treating colorectal cancer in actual clinical practice settings. More specifically, they can be used as a guide to obtaining informed consent from patients and choosing the method of treatment for each patient. Controversial issues were selected as clinical questions, and recommendations were made. Each recommendation is accompanied by a classification of the evidence and a classification of recommendation categories based on the consensus reached by the Guideline Committee members. Here, we present the English version of the JSCCR guidelines 2019.

Survival Benefit of and Indications for Adjuvant Chemotherapy for Resected Colorectal Liver Metastases-a Japanese Nationwide Survey.

BACKGROUND: The survival benefit of and indications for adjuvant chemotherapy (AC) for colorectal liver metastases (CRLM) remain unclear. METHODS: Patients who were diagnosed with liver-limited CRLM between 2005 and 2007 and subsequently underwent R0 resection without preoperative chemotherapy were identified in a Japanese nationwide survey. This overall cohort was divided into synchronous and metachronous CRLM cohorts. In each of the three cohorts, the patients that were given AC were matched with those treated with surgery alone via 1:1 propensity score (PS) matching. Recurrence-free survival (RFS) and overall survival (OS) after the initial hepatectomy were compared. RESULTS: The median follow-up period was 79.4 months and the overall, synchronous, and metachronous cohorts included 1145, 498, and 647 patients, respectively. After the PS matching, the patients' demographics were well balanced. AC was effective in terms of both RFS and OS in the overall cohort (RFS hazard ratio [HR] 0.784, p = 0.045; OS HR 0.716, p = 0.028) and synchronous cohort (RFS HR 0.677, p = 0.027; OS HR 0.642, p = 0.036), whereas AC was not effective in the metachronous cohort (RFS HR 0.875, p = 0.378; OS HR 0.881, p = 0.496). However, in the metachronous cohort, AC was effective in terms of OS in the subgroup that exhibited disease-free intervals of ≤ 1 year after primary tumor resection (RFS HR 0.667, p = 0.068; OS HR 0.572, p = 0.042). CONCLUSION: Adjuvant chemotherapy has a survival benefit for patients with resected CRLM. Synchronous CRLM is a favorable indication for AC, whereas in metachronous CRLM, the use of AC should be individualized according to each patient's risk factors.

Factors affecting R0 resection of colorectal cancer with synchronous peritoneal metastases: a multicenter prospective observational study by the Japanese Society for Cancer of the Colon and Rectum.

BACKGROUND: In Japan, R0 resection has been recommended for colorectal cancer patients with peritoneal metastases confined to the adjacent peritoneum and those with a few metastases to the distant peritoneum. R0 resection for M1c disease has drawn attention in Western countries and is currently considered an acceptable therapeutic option in the US National Comprehensive Cancer Network guidelines. However, clinical factors that affect the choice of R0 resection are unknown. METHODS: This multicenter, prospective, observational study was conducted by the Japanese Society for Cancer of the Colon and Rectum. Colorectal cancer patients with synchronous peritoneal metastases were enrolled at 28 institutions in Japan from October 2012 to December 2016. To determine factors affecting R0 resection and R1 resection with intended R0 resection, stepwise logistic regression analyses were performed on clinical factors including age, sex, performance status (PS), body mass index, peritoneal cancer index (PCI) score, presence of ascites, presence of distant metastases, and primary tumor site. RESULTS: R0/R1 resection was performed in 36 (31/5; 25%) of 146 patients. No distant metastases [odds ratio (OR) 52.9; 95% confidence interval (CI) 13.3-210.1; p < 0.0001], low PCI score (1-6) (OR 20.0; 95% CI 4.8-83.4; p < 0.0001), and high PS (0) (OR 2.40; 95% CI 0.66-8.68; p = 0.18) were independent factors affecting R0/R1 resection. PCI score and PS were also independent factors affecting R0/R1 resection in M1c patients without non-peritoneal distant metastases (n = 59). CONCLUSION: Distant metastases, PCI score, and PS are three factors which affect R0 resection for M1c disease.

[A Case of Intussusception Due to Sigmoid Colon Cancer].

A 78-year-old man was referred to our hospital with diarrhea, melena, and weight loss. During a digital rectal examination, a protuberant mass located 7-8 cm above the anal verge was palpable. Computed tomography(CT)scans of his chest, abdomen, and pelvis revealed an intestinal obstruction with a target sign in the lower rectum, indicating intussusception due to a sigmoid colon mass. A gastrografin enema examination revealed a typical filling defect with a crab claw sign in the rectum. However, the enema did not reduce the intussusception. The surgical findings showed that the sigmoid colon had slipped inside the rectum, consistent with the diagnostic imaging findings. A radical sigmoidectomy(D2)with diverting colostomy was performed to address the unprepared colon with accompanying edema. Pathology of the resected specimen revealed a type 2 tumor measuring 5 cm in size and comprising moderately differentiated adenocarcinoma(pT3pN0M0, pStage Ⅱ). The patient's postoperative course was uneventful, and his stoma was closed 2 months later. Intussusception occurs less frequently in adults than in children. In a case of bowel-within-bowel configuration, in which layers of the bowel are duplicated to form concentric rings, the target-like sign on CT images may be a useful diagnostic marker of colorectal intussusception.

A randomised-controlled trial of 1-year adjuvant chemotherapy with oral tegafur-uracil versus surgery alone in stage II colon cancer: SACURA trial.

BACKGROUND: Efficacy of adjuvant chemotherapy in patients with stage II colon cancer is still controversial. The SACURA trial is a randomised-controlled study evaluating the superiority of 1-year adjuvant treatment with oral tegafur-uracil (UFT) to surgery alone for stage II colon cancer. METHODS: Patients were randomly assigned to the surgery-alone group or UFT group (UFT at 500-600 mg/day for 5 days, followed by 2-day rest, for 1 year). The primary end-point was disease-free survival (DFS). Target sample size was 2000, determined with one-sided alpha of 0.05, power of 0.9 and assumed hazard ratio (HR) 0.729. RESULTS: A total of 1982 patients (997 in the surgery-alone group and 985 in the UFT group) were analysed. Median follow-up was 69.5 months, median age was 66 years and for stage IIA/IIB/IIC, the distribution was 84%/13%/3%. The 5-year DFS rate was 78.4% in the surgery-alone group and 80.2% in the UFT group. The HR for DFS was 0.91 (95% confidence interval [CI], 0.75-1.10; p = 0.31); superiority of UFT was not demonstrated. Approximately 9% of patients experienced second cancers, which consist 40.7% of the DFS events. The 5-year relapse-free and overall survival rates of the surgery-alone and UFT group were 84.6% and 87.2% (HR, 0.82; 95% CI, 0.65-1.04) and 94.3% and 94.5% (HR, 0.93; 95% CI, 0.66-1.31), respectively. Subgroup analysis failed to disclose superiority in prognosis of adding UFT to the patients with risk factors for recurrence. CONCLUSIONS: Superiority of 1-year adjuvant UFT over surgery alone was not demonstrated in stage II colon cancer. Patients with risk factors for recurrence did not benefit from UFT. TRIAL REGISTRATION: ClinicalTrials. Gov. #NCT00392899.

Planned Safety Analysis of the ACTS-CC 02 Trial: A Randomized Phase III Trial of S-1 With Oxaliplatin Versus Tegafur and Uracil With Leucovorin as Adjuvant Chemotherapy for High-Risk Stage III Colon Cancer.

BACKGROUND: This trial was designed to verify the superiority of 6 months of postoperative adjuvant chemotherapy with SOX (S-1 with oxaliplatin) with UFT (tegafur and uracil) with LV (leucovorin) in terms of disease-free survival in patients with high-risk stage III colon cancer. We report the results of a planned safety analysis. PATIENTS AND METHODS: Patients who underwent curative resection for high-risk stage III colon cancer (any T, N2, or positive nodes around the origin of the feeding arteries) were randomly assigned to receive either UFT/LV (300-600 mg/d UFT with 75 mg/d LV on days 1-28, every 35 days, for 5 cycles) or SOX (100 mg/m2 of oxaliplatin on day 1 with 80-120 mg/d S-1 on days 1-14, every 21 days, for 8 cycles). Treatment status and safety were evaluated. RESULTS: A total of 966 patients were enrolled, and 932 patients were included in safety analyses. The planned 6-month protocol treatment was received by 76.9% of the patients in the UFT/LV group and 65.8% of those in the SOX group. The overall incidence of any Grade adverse events (AEs) were 91.3% in the UFT/LV group and 98.7% in the SOX group, and those of Grade ≥ 3 AEs were 16.1% and 36.1%, respectively. As for Grade ≥ 3 AEs, leukopenia, neutropenia, thrombocytopenia, and sensory neuropathy were more common in the SOX group. The incidence of Grade ≥ 3 sensory peripheral neuropathy was 4.6% in the SOX group. CONCLUSION: The completion rate of adjuvant SOX and its incidence of AEs were acceptable in patients with colon cancer.