Preoperative and postoperative prognostic factors of patients with stage II/III lower rectal cancer without neoadjuvant therapy in the clinical trial (JCOG0212).

BACKGROUND: The JCOG0212 trial was a randomized controlled trial comparing mesorectal excision alone to mesorectal excision with lateral lymph node dissection for stage II/III lower rectal cancer patients without clinical lateral lymph node enlargement. This study aimed to identify clinicopathological prognostic factors for relapse-free survival and overall survival of lower rectal cancer in the trial. METHODS: Prospective data were selected from 663 patients with complete data. Uni and multivariable Cox regression model was applied to evaluate the preoperative and the combined preoperative and postoperative factors, respectively. Preoperative factors included age, sex, performance status, clinical T, clinical N and operative procedures. Postoperative factors included histological grade, pathological T, number of metastatic lymph nodes and number of dissected lymph nodes. No patient received neoadjuvant treatment. RESULTS: Regarding preoperative factors, multivariable analysis revealed that performance status 1 (vs. 0: HR 2.079, P = 0.0041) and cT4a (vs. cT2-3: HR 2.721, P = 0.0002) were independent risk factors for relapse-free survival, and those for overall survival were male (vs. female: HR 1.660, P = 0.0228) and cT4a (vs. cT2-3: HR 2.486, P = 0.0473). The only independent preoperative risk factor common for relapse-free survival and overall survival was cT4a. Taking preoperative and postoperative factors together, the number of metastatic lymph nodes was the only independent risk factor common for relapse-free survival and overall survival. CONCLUSIONS: Clinical stage II/III lower rectal cancer patients with cT4a should be a target of therapeutic development of neoadjuvant therapy. Postoperatively, intensive chemotherapy should be investigated for patients with more metastatic lymph nodes.

Application of targeted nanopore sequencing for the screening and determination of structural variants in patients with Lynch syndrome.

Lynch syndrome is a hereditary disease characterized by an increased risk of colorectal and other cancers. Germline variants in the mismatch repair (MMR) genes are responsible for this disease. Previously, we screened the MMR genes in colorectal cancer patients who fulfilled modified Amsterdam II criteria, and multiplex ligation-dependent probe amplification (MPLA) identified 11 structural variants (SVs) of MLH1 and MSH2 in 17 patients. In this study, we have tested the efficacy of long read-sequencing coupled with target enrichment for the determination of SVs and their breakpoints. DNA was captured by array probes designed to hybridize with target regions including four MMR genes and then sequenced using MinION, a nanopore sequencing platform. Approximately, 1000-fold coverage was obtained in the target regions compared with other regions. Application of this system to four test cases among the 17 patients correctly mapped the breakpoints. In addition, we newly found a deletion across an 84 kb region of MSH2 in a case without the pathogenic single nucleotide variants. These data suggest that long read-sequencing combined with hybridization-based enrichment is an efficient method to identify both SVs and their breakpoints. This strategy might replace MLPA for the screening of SVs in hereditary diseases.

Correction: Importance of gastric cancer for the diagnosis and surveillance of Japanese Lynch syndrome patients.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Importance of gastric cancer for the diagnosis and surveillance of Japanese Lynch syndrome patients.

Lynch syndrome (LS) is an autosomal dominantly inherited disease predisposed to not only colorectal cancer but also other LS-related tumors. Although the clinical and genetic characteristics of LS in Western countries have been well characterized, the information of Japanese LS is limited. As a collaborative study of Japanese Society for Cancer of the Colon and Rectum (JSCCR), we registered colorectal cancer (CRC) patients who fulfilled the modified Amsterdam II criteria including gastric cancer as an LS-related tumor. Among 4030 CRC patients initially registered in this project, 85 patients (2.1%) fulfilled the modified criteria. An additional 26 patients who met the same criteria were enrolled in the analysis. We analyzed three major responsible genes, MLH1, MSH2, and MSH6 by direct sequencing, and further performed multiplex ligation-dependent probe amplification for MLH1 and MSH2. Consequently, we identified pathogenic variants in 64 of the 111 patients comprising of 34 patients in MLH1, 28 in MSH2, and 2 in MSH6. It is of note that large structural alterations were found in 17 patients. Among the 64 patients, 11 patients would not have been enrolled in the analysis if gastric cancer were not included in the modified criteria. In addition, 10 of the 64 variant carriers (15.6%) had medical history of gastric cancer. Furthermore, the standardized incidence ratio of gastric cancer in the LS patients to the Japanese population is estimated to be as high as 20.2. These data underscore the importance of gastric cancer in the diagnosis and healthcare of Japanese LS patients.

Japanese genome-wide association study identifies a significant colorectal cancer susceptibility locus at chromosome 10p14.

Genome-wide association studies are a powerful tool for searching for disease susceptibility loci. Several studies identifying single nucleotide polymorphisms (SNP) connected intimately to the onset of colorectal cancer (CRC) have been published, but there are few reports of genome-wide association studies in Japan. To identify genetic variants that modify the risk of CRC oncogenesis, especially in the Japanese population, we performed a multi-stage genome-wide association study using a large number of samples: 1846 CRC cases and 2675 controls. We identified 4 SNP (rs7912831, rs4749812, rs7898455 and rs10905453) in chromosome region 10p14 associated with CRC; however, there are no coding or non-coding genes within this region of fairly extensive linkage disequilibrium (a 500-kb block) on 10p14. Our study revealed that the 10p14 locus is significantly correlated with susceptibility to CRC in the Japanese population, in accordance with the results of multiple studies in other races.

Mesorectal Excision With or Without Lateral Lymph Node Dissection for Clinical Stage II/III Lower Rectal Cancer (JCOG0212): A Multicenter, Randomized Controlled, Noninferiority Trial.

OBJECTIVE: The aim of the study was to confirm the noninferiority of mesorectal excision (ME) alone to ME with lateral lymph node dissection (LLND) in terms of efficacy. BACKGROUND: Lateral pelvic lymph node metastasis is occasionally found in clinical stage II or III lower rectal cancer, and ME with LLND is the standard procedure in Japan. ME alone, however, is the international standard surgical procedure for rectal cancer. METHODS: Eligibility criteria included histologically proven rectal cancer at clinical stage II/III; main lesion located in the rectum, with the lower margin below the peritoneal reflection; no lateral pelvic lymph node enlargement; Peformance Status of 0 or 1; and age 20 to 75 years. Patients were intraoperatively allocated to undergo ME with LLND or ME alone in a randomized manner. The primary endpoint was relapse-free survival, with a noninferiority margin for the hazard ratio of 1.34. Secondary endpoints included overall survival and local-recurrence-free survival. Analysis was by intention to treat. RESULTS: In total, 701 patients were randomized to the ME with LLND (n = 351) and ME alone (n = 350) groups. The 5-year relapse-free survival in the ME with LLND and ME alone groups were 73.4% and 73.3%, respectively (hazard ratio: 1.07, 90.9% confidence interval 0.84-1.36), with a 1-sided P value for noninferiority of 0.0547. The 5-year overall survival, and 5-year local-recurrence-free survival in the ME with LLND and ME alone groups were 92.6% and 90.2%, and 87.7% and 82.4%, respectively. The numbers of patients with local recurrence were 26 (7.4%) and 44 (12.6%) in the ME with LLND and ME alone groups, respectively (P = 0.024). CONCLUSIONS: The noninferiority of ME alone to ME with LLND was not confirmed in the intent-to-treat analysis. ME with LLND had a lower local recurrence, especially in the lateral pelvis, compared to ME alone.

Prognostic Impact of Intra-abdominal/Pelvic Inflammation After Radical Surgery for Locally Recurrent Rectal Cancer.

BACKGROUND: The influence of postoperative infectious complications, such as anastomotic leakage, on survival has been reported for various cancers, including colorectal cancer. However, it remains unclear whether intra-abdominal/pelvic inflammation after radical surgery for locally recurrent rectal cancer is relevant to its prognosis. OBJECTIVE: The purpose of this study was to evaluate factors associated with survival after radical surgery for locally recurrent rectal cancer. DESIGN: The prospectively collected data of patients were retrospectively evaluated. SETTINGS: This study was conducted at a single-institution tertiary care cancer center. PATIENTS: Between 1983 and 2012, patients who underwent radical surgery for locally recurrent rectal cancer with curative intent at the National Cancer Center Hospital were reviewed. MAIN OUTCOME MEASURES: Factors associated with overall and relapse-free survival were evaluated. RESULTS: During the study period, a total of 180 patients were eligible for analyses. Median blood loss and operation time for locally recurrent rectal cancer were 2022 mL and 634 minutes. Five-year overall and 3-year relapse-free survival rates were 38.6% and 26.7%. Age (p = 0.002), initial tumor stage (p = 0.03), pain associated with locally recurrent rectal cancer (p = 0.03), CEA level (p = 0.004), resection margin (p < 0.001), intra-abdominal/pelvic inflammation (p < 0.001), and surgery period (p = 0.045) were independent prognostic factors associated with overall survival, whereas CEA level (p = 0.01), resection margin (p = 0.002), and intra-abdominal/pelvic inflammation (p = 0.001) were associated with relapse-free survival. Intra-abdominal/pelvic inflammation was observed in 45 patients (25.0%). A large amount of perioperative blood loss was the only factor associated with the occurrence of intra-abdominal/pelvic inflammation (p = 0.007). LIMITATIONS: This study was limited by its retrospective nature and heterogeneous population. CONCLUSIONS: Intra-abdominal/pelvic inflammation after radical surgery for locally recurrent rectal cancer is associated with poor prognosis. See Video Abstract at http://journals.lww.com/dcrjournal/Pages/videogallery.aspx.

Postoperative Chemoradiotherapy After Local Resection for High-Risk T1 to T2 Low Rectal Cancer: Results of a Single-Arm, Multi-Institutional, Phase II Clinical Trial.

BACKGROUND: After treatment with local excision for TNM stage I low rectal cancer, the risk of local recurrence is not only high for T2 lesions but also for T1 lesions with features of massive invasion to the submucosal layer and/or lymphovascular invasion. OBJECTIVE: The purpose of this study was to determine the efficacy of chemoradiotherapy combined with local excision in the treatment of T1 to T2 low rectal cancer. DESIGN: We conducted a prospective, single-arm, phase II trial. SETTINGS: This was a multicenter study. PATIENTS: From April 2003 to October 2010, 57 patients were treated with local excision after additional external beam irradiation (45 Gy) plus continuous 5-week intravenous injection of 5-fluorouracil (250 mg/m per day) at 10 domestic hospitals. Fifty-three patients had clinical T1N0 lesions, and 4 had T2N0 lesions in the low rectum, located below the peritoneal reflection. MAIN OUTCOMES MEASURES: The primary end point was disease-free survival at 5 years. RESULTS: The completion rate for full-dose chemoradiotherapy was 86% (49/57). Serious, nontransient treatment-related complications were not reported. With a median follow-up of 7.3 years after local excision, the 5-year disease-free survival rate was 94% for the 53 patients with T1 lesions and 75% for the 4 patients with T2 lesions. There were 2 local recurrences during the entire observation period. Anal function after local excision and chemoradiation were kept at almost the same levels as observed before treatment. LIMITATIONS: The study was limited by the small number of registered T2 rectal cancers, retrospective evaluations of quality of life, and the exclusion of poorly differentiated adenocarcinoma (a high-risk feature of T1 lesions). CONCLUSIONS: The addition of chemoradiotherapy to local excision of T1 rectal adenocarcinomas with poor prognostic features including deep submucosal invasion and lymphovascular invasion could improve on less favorable historic oncologic outcomes of local excision alone in this high-risk group for lymph node metastasis. See Video Abstract at http://links.lww.com/DCR/A421.

Characteristics and Clinical Outcomes of Duodenal Neoplasia in Japanese Patients With Familial Adenomatous Polyposis.

BACKGROUND: After colorectal cancer and desmoid tumors, duodenal adenocarcinoma is the next leading cause of death in familial adenomatous polyposis (FAP) patients, but it has not been thoroughly investigated. PATIENTS AND METHODS: To investigate the clinical course of duodenal neoplasia, including adenoma and cancer, we investigated 77 Japanese FAP patients treated at the National Cancer Center Hospital, Tokyo, Japan. We evaluated the clinicopathologic features, Spigelman severity score, and management of duodenal neoplasms. Data were acquired from a prospectively enrolled database. RESULTS: Fifty-one (66%) of the 77 FAP patients had duodenal neoplasia during this observational period, and 47 of 51 patients had extra-ampulla duodenal neoplasia; 42 (58%) had duodenal neoplasms (extra-ampulla), 4 had duodenal adenomas with high-grade dysplasia (HGD), and 1 had invasive carcinoma. Among the 45 patients (extra-ampulla) with duodenal adenoma with HGD or low-grade dysplasia, 8 (18%) patients were treated using endoscopic resection (ER). During the short observation period, ER was performed only in HGD cases. None of the patients died from duodenal neoplasia. In total, during the surveillance period, duodenal HGD was detected in 5 (63%) of 8 patients graded as Spigelman stage IV; HGD was not detected in stage 0 (n=33), I (n=0), II (n=12), or III (n=20) patients. CONCLUSIONS: Short-interval endoscopic surveillance and appropriate ER may help prevent duodenal invasive carcinoma. In addition, there was little development of invasive carcinoma during the follow-up. The Spigelman classification is beneficial for the risk assessment of duodenal neoplasia in Japanese FAP patients.

Is There Any Reason to Still Consider Lateral Lymph Node Dissection in Rectal Cancer? Rationale and Technique.

Nodal dissemination in locally advanced rectal cancer occurs mainly in two directions: upward and lateral. Lateral node involvement has been demonstrated; however, lateral lymph node dissection (LLND) is not routinely performed in Western countries and the focus is more on neoadjuvant treatment regimens. The main reasons for this are the high morbidity associated with the operation and the uncertain oncological benefit. There is, however, recent evidence that in selected cases, neoadjuvant treatment combined with total mesorectal excision only might not be sufficient. In this article, the historical developments in the East and the West, the current evidence regarding lateral nodal disease, and the surgical steps in the LLND are discussed.

Comparison of clinical features between suspected familial colorectal cancer type X and Lynch syndrome in Japanese patients with colorectal cancer: a cross-sectional study conducted by the Japanese Society for Cancer of the Colon and Rectum.

OBJECTIVE: The characteristics of familial colorectal cancer type X are poorly defined. Here we aimed to clarify the differences in clinical features between suspected familial colorectal cancer type X and Lynch syndrome in Japanese patients. METHODS: We performed germline mutation analyses of mismatch repair genes in 125 patients. Patients who met the Amsterdam Criteria I but lacked mismatch repair gene mutations were diagnosed with suspected familial colorectal cancer type X. RESULTS: We identified 69 patients with Lynch syndrome and 25 with suspected familial colorectal cancer type X. The frequencies of gastric and extracolonic Lynch syndrome-associated cancers were lower with suspected familial colorectal cancer type X than with Lynch syndrome. The number of organs with Lynch syndrome-associated cancer was significantly lower with suspected familial colorectal cancer type X than with Lynch syndrome. The cumulative incidence of extracolonic Lynch syndrome-associated cancer was significantly lower with suspected familial colorectal cancer type X than with Lynch syndrome. We estimated that the median cancer risk in 60-year-old patients with Lynch syndrome was 89, 36 and 24% for colorectal, endometrial and gastric cancers, respectively. Analyses of family members, including probands, revealed that the median age at diagnosis of extracolonic Lynch syndrome-associated cancer was significantly older with suspected familial colorectal cancer type X than with Lynch syndrome. The frequency of extracolonic Lynch syndrome-associated cancer was significantly lower with suspected familial colorectal cancer type X than with Lynch syndrome. CONCLUSION: A significant difference in extracolonic Lynch syndrome-associated cancer was evident between suspected familial colorectal cancer type X and Lynch syndrome.

Relationship between smoking and multiple colorectal cancers in patients with Japanese Lynch syndrome: a cross-sectional study conducted by the Japanese Society for Cancer of the Colon and Rectum.

The positive correlation between smoking and cancer risk is well estimated in sporadic colorectal cancer, whereas little is known with regard to Lynch syndrome-associated colorectal cancer. A total of 118 familial colorectal cancer patients from the Hereditary Nonpolyposis Colorectal Cancer Registry and Genetic Testing Project of the Japanese Society for Cancer of the Colon and Rectum, were assessed to determine whether smoking alters the incidence of multiple colorectal cancers. In male patients with Lynch syndrome (n = 29), the incidence of multiple colorectal cancers in patients who had ever smoked (smoking duration: median of 19 years) was higher than that in those who never smoked (58.8% vs. 10.0%, P = 0.02). The cumulative risk for metachronous colorectal cancer was significantly higher in male Lynch syndrome patients who had previously smoked than in those who had never smoked (P = 0.03). Our data suggest that long-term cigarette smoking might be a strong risk factor for the development of multiple colorectal cancers in male Lynch syndrome patients.

A phase I trial of preoperative S-1 in combination with oxaliplatin and pelvic radiation for lower rectal cancer with T4 and lateral pelvic lymph node metastasis.

BACKGROUND: The purpose of this phase I study of the dose escalation of oxaliplatin in combination with oral S-1 and pelvic radiation preoperatively for poor-risk lower rectal cancer was to determine the dose-limiting toxicity (DLT) and recommended dose of oxaliplatin. METHODS: Patients with cT4 and lateral pelvic lymph node metastasis, and without distant metastasis (cM0), were treated with weekly oxaliplatin, oral S-1 40 mg/m(2) twice daily for 5 days a week, and radiation. A total of 5 weekly doses of oxaliplatin were planned. RT was administered to a total dose of 50.4 Gy in 28 fractions. RESULTS: We enrolled 11 patients between December 2009 and January 2012. DLTs were observed at dose level 1 (50 mg/m(2)) in two patients, one of whom experienced grade 3 aspartate aminotransferase elevation and a grade 3 alanine aminotransferase increase, and the other developed grade 4 hypokalemia and a grade 3 alanine aminotransferase increase. Five patients at dose level 2 (60 mg/m(2)) showed no DLTs. The hematological toxicities in all patients were mild and reversible. One patient showed distant metastasis after chemoradiation. Ten of the 11 patients achieved R0 resection by mesorectal resection and lateral lymph node dissection; three of the 10 underwent combined resection of the other organs. CONCLUSION: This phase I trial of preoperative S-1 in combination with oxaliplatin and radiation for lower rectal cancer with T4 and lateral pelvic lymph node metastasis revealed that the recommended dose of oxaliplatin was 60 mg/m(2) weekly.

Short-term surgical outcomes from a randomized controlled trial to evaluate laparoscopic and open D3 dissection for stage II/III colon cancer: Japan Clinical Oncology Group Study JCOG 0404.

OBJECTIVE: A randomized controlled trial to confirm the non-inferiority of laparoscopic surgery to open surgery in terms of overall survival was conducted, and short-term surgical outcomes are demonstrated. BACKGROUND: The efficacy and safety outcome of laparoscopic surgery for clinical stages II/III colon cancer undergoing Japanese D3 dissection are still unclear. METHODS: Eligibility criteria included colon cancer; tumor located in the cecum, ascending, sigmoid, or rectosigmoid colon; T3 or T4 without involvement of other organs; N0-2; and M0. Patients were randomized preoperatively and underwent tumor resection with D3 dissection. Safety analyses were conducted by per-protocol set. RESULTS: A total of 1057 patients were randomized between October 2004 and March 2009. By per-protocol set, 524 patients who underwent open surgery and 533 patients who underwent laparoscopic surgery were analyzed. D3 dissection was performed in 521 (99.4%) patients in the open surgery arm and 529 (99.2%) patients in the laparoscopic surgery arm. Conversion to open surgery was needed for 29 (5.4%) patients. Patients assigned to laparoscopic surgery had less blood loss (P < 0.001), although laparoscopic surgery lasted 52 minutes longer (P < 0.001). Laparoscopic surgery was associated with a shorter time to pass first flatus, decreased use of analgesics after 5 postoperative days, and a shorter hospital stay. Morbidity [14.3% (76/533) vs 22.3% (117/524), P < 0.001] was lower in the laparoscopic surgery arm. CONCLUSIONS: Short-term surgical safety and clinical benefits of laparoscopic D3 dissection were demonstrated. The primary endpoint will be reported after the primary analysis, planned for 2014.

A randomized controlled trial of the conventional technique versus the no-touch isolation technique for primary tumor resection in patients with colorectal cancer: Japan Clinical Oncology Group Study JCOG1006.

A randomized controlled trial is currently being conducted in Japan to demonstrate the superiority of the no-touch isolation technique over the conventional technique for patients with potentially curative colon and rectosigmoid cancer. The conventional technique procedure gives first priority to mobilization of the tumor-bearing segment of the colon, which is followed by central vascular ligation and ligation of other vasculature. Conversely, the no-touch isolation technique gives first priority to central vascular ligation, which is followed by mobilization of the tumor-bearing segment of the colon. A total of 850 patients will be enrolled in this trial. The primary endpoint is disease-free survival. Secondary endpoints are overall survival, relapse-free survival, liver metastasis-free survival, mode of recurrence, surgical morbidity, adverse events due to postoperative chemotherapy, serious adverse events and short-term clinical outcomes.

Quality control by photo documentation for evaluation of laparoscopic and open colectomy with D3 resection for stage II/III colorectal cancer: Japan Clinical Oncology Group Study JCOG 0404.

OBJECTIVE: The quality of surgery with D3 resection in randomized controlled clinical trial [Japan Clinical Oncology Group study (JCOG0404)] was assessed by evaluation of the photo documentation of both open and laparoscopic surgeries. METHODS: A multi-institutional randomized-controlled trial (JCOG0404) was conducted to evaluate open and laparoscopic D3 resection (complete mesocolic excision + ligation and dissection at the root of the main vessels) for Stage II/III colon cancer (UMIN-CTR number C000000105). A total of 1057 (open, 528; laparoscopic, 529) eligible patients were enrolled. For quality control, it was ensured that the surgeries were performed by accredited surgeons, and a central committee reviewed each surgery on the basis of the submitted photographs of the resected field, specimen and skin incision. RESULTS: For right-sided tumors, the rate of D3 resection was 98.5% (131/133) in the open arm and 100% (136/136) in the laparoscopic arm, and for left-sided tumors, they were 97.9% (322/329) and 98.2% (320/326), respectively. Sufficient length of the resected longitudinal margin was ensured in all cases. The skin incisions made in all the cases were <8 cm as defined in the protocol in laparoscopic arm. CONCLUSIONS: Completion of high quality surgery with D3 resection was confirmed in JCOG0404 by central peer review of photographs of the surgical procedures in addition to operator regulations. This study suggests that the central review of the photo documentation is one of the important tools to assure a quality control of surgical technique in the Phase III randomized-controlled study.

Early detection of metachronous bile duct cancer in Lynch syndrome: report of a case.

Lynch syndrome is an autosomal dominant disease associated with a high incidence of colorectal, endometrial, stomach, ovarian, pancreatic, ureter and renal pelvis, bile duct and brain tumors. The syndrome can also include sebaceous gland adenomas and keratoacanthomas, and carcinoma of the small bowel. The lifetime risk for bile duct cancer in patients with Lynch syndrome is approximately 2 %. The present report describes a case of Lynch syndrome with metachronous bile duct cancer diagnosed at an early stage. The patient was a 73-year-old Japanese male who underwent a successful left lobectomy of the liver, and there was no sign of recurrence for 2 years postoperative. However, this patient harbored a germline mutation in MLH1, which prompted diagnostic examinations for noncolorectal tumors when a periodic surveillance blood examination showed abnormal values of hepatobiliary enzymes. Although most patients with bile duct cancer are diagnosed at an advanced stage, the bile duct cancer was diagnosed at an early stage in the present patient due to the observation of the gene mutation and the preceding liver tumor. This case illustrates the importance of continuous surveillance for extracolonic tumors, including bile duct cancer, in patients with Lynch syndrome.

The rs6983267 SNP is associated with MYC transcription efficiency, which promotes progression and worsens prognosis of colorectal cancer.

BACKGROUND: The oncogenic single nucleotide polymorphism rs6983267, located on 8q24.21, may affect copy number aberrations and/or expression profiles in colorectal cancer (CRC). We investigated the role of this single nucleotide polymorphism in the clinical outcome of CRC. METHODS: Array comparative genomic hybridization (aCGH) and oligomicroarrays were performed on cancer cells from 157 primary CRC tissues. Expression profiles were analyzed by means of extraction expression module (EEM) analyses. Mutations in TP53, KRAS, and BRAF and microsatellite instability were also examined in 107 of the 157 cases. RESULTS: aCGH analysis revealed two clusters; more frequent genomic copy number alteration (CNA) was observed in the 89 cases in cluster B than in the 18 cases in cluster A. The average CNA was higher in samples containing the major allele (GT/TT) of rs6983267 than in those containing the minor allele (GG). Additionally, MYC expression was the highest in samples containing the GG allele (n = 18), followed by the GT and TT alleles (n = 41 and 48, respectively). EEM analysis revealed dominant up-regulation of MYC in samples containing the minor allele. Moreover, the presence of the minor allele in a MYC-positive, CNA-negative context predicted a poorer prognosis than the presence of the major allele in a MYC-negative, CNA-positive context in CRC. CONCLUSIONS: The presence of the minor allele of rs6983267 at 8q24.21 worsened the prognosis of CRC through up-regulation of MYC transcription. Furthermore, progression of CRC may require global CNA in the presence of the major allele and with lack of MYC transcription.

Postoperative morbidity and mortality after mesorectal excision with and without lateral lymph node dissection for clinical stage II or stage III lower rectal cancer (JCOG0212): results from a multicentre, randomised controlled, non-inferiority trial.

BACKGROUND: Mesorectal excision is the international standard surgical procedure for lower rectal cancer. However, lateral pelvic lymph node metastasis occasionally occurs in patients with clinical stage II or stage III rectal cancer, and therefore mesorectal excision with lateral lymph node dissection is the standard procedure in Japan. We did a randomised controlled trial to confirm that the results of mesorectal excision alone are not inferior to those of mesorectal excision with lateral lymph node dissection. METHODS: This study was undertaken at 33 major hospitals in Japan. Eligibility criteria included histologically proven rectal cancer of clinical stage II or stage III, with the main lesion located in the rectum with the lower margin below the peritoneal reflection, and no lateral pelvic lymph node enlargement. After surgeons had confirmed macroscopic R0 resection by mesorectal excision, patients were intraoperatively randomised to mesorectal excision alone or with lateral lymph node dissection. The groups were balanced by a minimisation method according to clinical N staging (N0 or N1, 2), sex, and institution. Allocated procedure was not masked to investigators or patients. This study is now in the follow-up stage. The primary endpoint is relapse-free survival and will be reported after the primary analysis planned for 2015. Here, we compare operation time, blood loss, postoperative morbidity (grade 3 or 4), and hospital mortality between the two groups. Analysis was by intention-to-treat. This trial is registered with ClinicalTrials.gov, number NCT00190541. FINDINGS: 351 patients were randomly assigned to mesoretcal excision with lateral lymph node dissection and 350 to mesorectal excision alone, between June 11, 2003, and Aug 6, 2010. One patient in the mesorectal excision alone group underwent lateral lymph node dissection, but was analysed in their assigned group. Operation time was significantly longer in the mesorectal excision with lateral lymph node dissection group (median 360 min, IQR 296-429) than in the mesorectal excision alone group (254 min, 210-307, p<0·0001). Blood loss was significantly higher in the mesorectal excision with lateral lymph node dissection group (576 mL, IQR 352-900) than in the mesorectal excision alone group (337 mL, 170-566; p<0·0001). 26 (7%) patients in the mesorectal excision with lateral lymph node dissection group had lateral pelvic lymph node metastasis. Grade 3-4 postoperative complications occurred in 76 (22%) patients in the mesorectal excision with lateral lymph node dissection group and 56 (16%) patients in the mesorectal excision alone group. The most common grade 3 or 4 postoperative complication was anastomotic leakage (18 [6%] patients in the mesorectal excision with lateral lymph node dissection group vs 13 [5%] in the mesorectal excision alone group; p=0·46). One patient in the mesorectal excision with lateral lymph node dissection group died of anastomotic leakage followed by sepsis. INTERPRETATION: Mesorectal excision with lateral lymph node dissection required a significantly longer operation time and resulted in significantly greater blood loss than mesorectal excision alone. The primary analysis will help to show whether or not mesorectal excision alone is non-inferior to mesorectal excision with lateral lymph node dissection. FUNDING: National Cancer Center, Ministry of Health, Labour and Welfare of Japan.

Increased risk for CRC in diabetic patients with the nonrisk allele of SNPs at 8q24.

BACKGROUND: Colorectal cancer (CRC) oncogenesis was considered to be determined by interactions between genetic and environmental factors. Specific interacting factors that influence CRC morbidity have yet to be fully investigated. METHODS: A multi-institutional collaborative study with 1511 CRC patients and 2098 control subjects was used to compare the odds ratios for the occurrence of polymorphisms at 11 known single nucleotide polymorphisms (SNPs). TaqMan PCR and questionnaires were used to evaluate the effects of environmental exposures. RESULTS: Variants of rs6983267 on 8q24 were the most significant markers of risk for CRC (odds ratio 1.16, 95% confidence interval 1.06-1.27, P = 0.0015). Non-insulin-dependent diabetes mellitus (DM), a higher body mass index at age 20, and meat consumption were environmental risk factors, whereas a tuna-rich diet and vitamin intake were protective factors. The cohort of rs6983267 SNP major (T) allele at 8q24 and DM had a 1.66-fold higher risk ratio than the cohort of major allele patients without DM. CONCLUSIONS: We confirmed that interactions between the genetic background and environmental factors are associated with increased risk for CRC. There is a robust risk of the minor G allele at the 8q24 rs6983267 SNP; however, a major T allele SNP could more clearly reveal a correlation with CRC specifically when DM is present.