Protocol for a single-arm confirmatory trial of adjuvant chemoradiation for patients with high-risk rectal submucosal invasive cancer after local resection: Japan Clinical Oncology Group Study JCOG1612 (RESCUE study)

IntroductionIntestinal resection with lymph node dissection is the current standard treatment for high-risk lower rectal submucosal invasive cancer after local resection; however, surgery affects patients’ quality of life due to stoma placement or impaired anal sphincter function. A recent study demonstrated that adjuvant chemoradiation yields promising results.Methods and analysisThis study aims to confirm the non-inferiority of adjuvant chemoradiation, consisting of capecitabine and concurrent radiotherapy (45 Gy in 25 fractions), measured by 5-year relapse-free survival (RFS), over standard surgery in patients with high-risk lower rectal submucosal invasive cancer after local resection. The primary endpoint is 5 year RFS. The secondary endpoints are 10 years RFS, 5-year and 10-year overall survival, 5-year and 10-year local RFS, 5-year and 10-year proportion of anus-preservation without stoma, Wexner score, low anterior resection syndrome score, adverse events and serious adverse events. During the 5-year trial period, 210 patients will be accrued from 65 Japanese institutions.Ethics and disseminationThe National Cancer Center Hospital East Certified Review Board approved this study protocol in October 2018. The study is conducted in accordance with the precepts established in the Declaration of Helsinki and Clinical Trials Act. Written informed consent will be obtained from all eligible patients prior to registration. The primary results of this study will be published in an English article. In addition, the main results will be published on the websites of Japan Clinical Oncology Group (www.jcog.jp) and jRCT (https://jrct.niph.go.jp/). As to data curation, it has not been prepared yet.Trial registration numberjRCT1031180076

Optical evaluation: the crux for effective management of colorectal neoplasia

Advances in minimally invasive tissue resection techniques now allow for the majority of early colorectal neoplasia to be managed endoscopically. To optimize their respective risk–benefit profiles, and, therefore, appropriately select between endoscopic mucosal resection, endoscopic submucosal dissection, and surgery, the endoscopist must accurately predict the risk of submucosal invasive cancer and estimate depth of invasion. Herein, we discuss the evidence and our approach for optical evaluation of large (⩾ 20 mm) colorectal laterally spreading lesions.

Validity of conventional endoscopy using “non-extension sign” for optical diagnosis of colorectal deep submucosal invasive cancer

Background and study aims The non-extension sign relates to a localized increase in thickness and rigidity due to deep submucosal invasive (SM-d: depth of 1000 μm or more) cancer. The present study aimed to evaluate the efficacy of the non-extension sign in assessing the optical diagnosis of colorectal SM-d cancer. Patients and methods We retrospectively analyzed 309 patients with 315 early colorectal cancers that had been endoscopically or surgically resected. The non-extension sign was judged from chromoendoscopy (CE) using conventional white-light imaging with indigo carmine, and is taken to be positive when any one of the findings of rigidity of a circular arc, trapezoid elevation, or converging mucosal folds are seen. We assessed comparing the accuracy of CE, magnifying chromoendoscopy (M-CE), and magnifying narrow-band imaging (M-NBI) for the optical diagnosis of colorectal SM-d cancer. Results Sensitivity, specificity, and accuracy for the diagnosis of SM-d cancer were 66.0 %, 95.8 %, and 86.3 % for CE; 80 %, 90.7 %, and 87.3 % for M-CE; and 65.0 %, 94.4 %, and 85.1 % for M-NBI, respectively. The specificity of CE was significantly higher than that of M-CE (P = 0.034). The sensitivity of M-CE was significantly higher than that of CE (P = 0.026). In a comparison of positive and negative groups for the non-extension sign in SM-d cancer, SM invasion was significantly deeper in the positive group than in the negative group (3012.5 μm vs 2002.4 μm, respectively; P < 0.0001) and the rate of lymphovascular invasion was significantly higher in the positive group than in the negative group (63.6 % vs 41.2 %, respectively; P = 0.032). Conclusions The non-extension sign offers high diagnostic specificity for SM-d cancer, and surgery should be considered in patients with a positive non-extension sign.

Safe Transanal Tumor Resection Using a Harmonic Scalpel

We performed a safe and simple transanal tumor resection involving total layer resection using a harmonic scalpel as a resecting device. Here we report the results of our experience with this technique between 2005 and 2011. This study involved 32 patients who underwent transanal tumor resection using a harmonic scalpel. The subjects comprised 18 men and 14 women ranging in age from 34 to 87 years (mean: 64.5 years). The tumors measured 8 to 70 mm (mean: 31 mm) in diameter. The operation took 7 to 86 minutes (mean: 29 minutes), and the amount of bleeding was 0 to 165 mL (mean: 16.2 mL). There was no intraoperative blood loss that necessitated hemostatic procedures. Histopathologically, the lesions included hyperplastic polyp in 1 case, adenoma in 9, carcinoma in situ in 7, submucosal invasive cancer in 6, muscularis propria cancer in 4, carcinoid in 1, malignant lymphoma in 1, gastrointestinal stromal tumor in 1, mucosal prolapsed syndrome in 1, and mucosa-associated lymphoid tissue lymphoma in 1. With our technique, en bloc resection was achieved in all patients, and the use of a harmonic scalpel enabled us to complete the operation within 30 minutes, on average, without intraoperative bleeding.