Teruhito Kishihara

Treatment strategy for rectal carcinoids: a clinicopathological analysis of 229 cases at a single cancer institution.

Background and Aim:  A treatment strategy for tumors with only venous invasion and characteristics of small rectal carcinoids with metastasis have not been clearly documented. The present study aims to determine the risk factors for lymph node metastasis and to elucidate characteristics of small tumors with metastasis.

Risk factors for bleeding after endoscopic submucosal dissection of colorectal neoplasms

AIM To investigate the risk factors for delayed bleeding following endoscopic submucosal dissection (ESD) treatment for colorectal neoplasms. METHODS We retrospectively reviewed the medical records of 317 consecutive patients with 325 lesions who underwent ESD for superficial colorectal neoplasms at our hospital from January 2009 to June 2013. Delayed post-ESD bleeding was defined as bleeding that resulted in overt hematochezia 6 h to 30 d after ESD and the observation of bleeding spots as confirmed by repeat colonoscopy or a required blood transfusion. We analyzed the relationship between risk factors for delayed bleeding following ESD and the following factors using univariate and multivariate analyses: age, gender, presence of comorbidities, use of antithrombotic drugs, use of intravenous heparin, resected specimen size, lesion size, lesion location, lesion morphology, lesion histology, the device used, procedure time, and the presence of significant bleeding during ESD. RESULTS Delayed post-ESD bleeding was found in 14 lesions from 14 patients (4.3% of all specimens, 4.4% patients). Patients with episodes of delayed post-ESD bleeding had a mean hemoglobin decrease of 2.35 g/dL. All episodes were treated successfully using endoscopic hemostatic clips. Emergency surgery was not required in any of the cases. Blood transfusion was needed in 1 patient (0.3%). Univariate analysis revealed that lesions located in the cecum (P = 0.012) and the presence of significant bleeding during ESD (P = 0.024) were significantly associated with delayed post-ESD bleeding. The risk of delayed bleeding was higher for larger lesion sizes, but this trend was not statistically significant. Multivariate analysis revealed that lesions located in the cecum (OR = 7.26, 95%CI: 1.99-26.55, P = 0.003) and the presence of significant bleeding during ESD (OR = 16.41, 95%CI: 2.60-103.68, P = 0.003) were independent risk factors for delayed post-ESD bleeding. CONCLUSION Location in the cecum and significant bleeding during ESD predispose patients to delayed post-procedural bleeding. Therefore, careful and additional management is recommended for these patients.

Successful Use of Endoscopic Argon Plasma Coagulation for Hemorrhagic Radiation Cystitis: A Case Report

Hemorrhagic radiation cystitis is an example of a typical radiotherapy-induced adverse event. However, the optimal treatment for hemorrhagic radiation cystitis is not known. There are limited data regarding the use of argon plasma coagulation for hemorrhagic radiation cystitis. Here, we present the use of argon plasma coagulation using a gastrointestinal endoscope to treat hemorrhagic radiation cystitis. The patient was a 75-year-old male patient with hemorrhagic radiation cystitis due to external beam irradiation for prostate adenocarcinoma. Six years after radiotherapy, the patient presented with macroscopic hematuria over the preceding 4 months, and laboratory investigations revealed a low hemoglobin level. The hematuria was not controlled with 2 days of bladder irrigation using normal saline. Thus, argon plasma coagulation using an upper gastrointestinal endoscope was considered for treatment of the hemorrhagic radiation cystitis. The cystoscopic examination revealed diffuse radiation cystitis with oozing telangiectasia and coagula. All of the bleeding sites and telangiectasia were coagulated using argon plasma coagulation. Following treatment, the patients clinical symptoms improved and did not recur. The hemoglobin level also recovered. No complications associated with the treatment were observed during the 6-month follow-up period. Thus, argon plasma coagulation using a gastrointestinal endoscope is a safe and effective treatment for hemorrhagic radiation cystitis.

RE‐EPITHELIALIZATION OF SQUAMOUS EPITHELIUM FOR A RADIATION‐INDUCED RECTAL ULCER WHILE GIVING AN ECABET SODIUM ENEMA

The present patient developed a severe rectal ulcer more than 1 month after having received external beam radiation therapy for prostate cancer. Surveillance endoscopy every 3 months demonstrated healing of this rectal ulcer using a novel therapy. He was given enemas with ecabet sodium, which provides physical protection and promotes healing by increasing prostaglandin E2, and this process induced squamous metaplasia that halted the progression of the ulcer of radiation proctitis as a late‐phase reaction. Intrapapillary capillary loops were visualized with magnified narrow band imaging at the healing ulcer site as seen via the esophagus and, moreover, demonstrated histologically.

Advantages of magnifying narrow-band imaging for diagnosing colorectal cancer coexisting with sessile serrated adenoma/polyp.

In the present study, we investigated the advantages of narrow‐band imaging (NBI) for efficient diagnosis of sessile serrated adenoma/polyp (SSA/P). The main objective of this study was to analyze the characteristic features of cancer coexisting with serrated lesion by carrying out NBI.

Cancer emerging from the recurrence of sessile serrated adenoma/polyp resected endoscopically 5 years ago

Since the serrated neoplastic pathway has been regarded as an important pathway of colorectal carcinogenesis, few reports have been published on clinical cases of cancer derived from sessile serrated adenoma/polyp, especially on recurrence after resected sessile serrated adenoma/polyp. An elderly woman underwent endoscopic mucosal resection of a flat elevated lesion, 30 mm in diameter, in the ascending colon; the histopathological diagnosis at that time was a hyperplastic polyp, now known as sessile serrated adenoma/polyp. Five years later, cancer due to the malignant transformation of the sessile serrated adenoma/polyp was detected at the same site. The endoscopic diagnosis was a deep invasive carcinoma with a remnant sessile serrated adenoma/polyp component. The carcinoma was surgically removed, and the pathological diagnosis was an adenocarcinoma with sessile serrated adenoma/polyp, which invaded the muscularis propria. The surgically removed lesion did not have a B-RAF mutation in either the sessile serrated adenoma/polyp or the carcinoma; moreover, the initial endoscopically resected lesion also did not have a B-RAF mutation. Immunohistochemistry confirmed negative MLH1 protein expression in only the cancer cells. Lynch syndrome was not detected on genomic examination. The lesion was considered to be a cancer derived from sessile serrated adenoma/polyp recurrence after endoscopic resection, because both the surgically and endoscopically resected lesions were detected at the same location and had similar pathological characteristics, with a serrated structure and low-grade atypia. Furthermore, both lesions had a rare diagnosis of a sessile serrated adenoma/polyp without B-RAF mutation. This report highlights the need for the follow-up colonoscopy after endoscopic resection and rethinking our resection procedures to improve treatment.

Advantages of magnifying narrow‐band imaging (NBI) for diagnosing the colorectal cancer coexisting with sessile serrated adenoma/polyp (SSA/P)

In the present study, we investigated the advantages of narrow‐band imaging (NBI) for efficient diagnosis of sessile serrated adenoma/polyp (SSA/P). The main objective of this study was to analyze the characteristic features of cancer coexisting with serrated lesion by carrying out NBI.

Endoscopic criteria to evaluate tumor response of rectal cancer to neoadjuvant chemoradiotherapy using magnifying chromoendoscopy

BACKGROUND AND AIMS Precise endoscopic assessment of complete response to neoadjuvant chemoradiotherapy before surgery is important for optimizing surgical and non-surgical treatment. We prospectively evaluated the accuracy of the newly proposed endoscopic criteria to identify complete response, using magnifying chromoendoscopy. METHODS New endoscopic criteria were created to define endoscopic complete response, near complete response and incomplete response, using magnifying chromoendoscopy. The criteria contained notable endoscopic findings, including shape of the scar, state of the ulcer, finding of white moss, presence of residual protruded nodules, regenerated pits of the scar, presence of neoplastic pit patterns, and extension of rectal wall. Seventy-nine patients with rectal cancer who received neoadjuvant chemoradiotherapy were prospectively evaluated 1-3 days before resection. Diagnostic accuracy to identify pathological complete response and interobserver agreement among a supervising colonoscopist and two trainees were investigated. RESULTS Pathological complete response was obtained in 17 patients (21.5%). The diagnostic accuracy of endoscopic complete response was 85%, with a sensitivity of 47%, specificity of 97%, positive predictive value of 80% and negative predictive value of 77%. The kappa-value for interobserver agreement across 3 doctors was 0.57 (standard error, 0.74; 95% confidence interval, 0.39-0.76). CONCLUSION The newly proposed endoscopic criteria using magnifying chromoendoscopy achieved excellent diagnostic accuracy to determine good responders to neoadjuvant chemoradiotherapy in rectal cancer, with fair interobserver agreement. The criteria could be clinically useful to select patients for non-surgical management.

Endoscopic Diagnosis of Anal Canal Cancer

肛門管癌は，体表に近いにもかかわらず進行癌で発見されるものが多い．その理由は，羞恥心から来院が遅れること，確定診断が遅れることなどが主な原因と考えられる．頻度はそれほど高くはないが，過去3年間に当院で経験した直腸癌380例中肛門管癌は12例(3.2%）で，進行癌が8例，早期癌4例であった．内視鏡診断は，肛門部を注意して観察することで早期診断可能であるが，反転観察が重要である．通常の観察では肛門管は接線方向の観察になり病変部の正面視は不可能である．反転しスコープ軸を回転させることで肛門管の観察は可能となる．さらに，色素撒布と拡大観察を加える腫瘍ピットを観察することで腺癌の診断が可能となる．さらに，NBIを用いた拡大観察を行うことで扁平上皮癌の診断が可能である．すなわち，食道のdysplasiaや癌でみられるものと同様の血管パターンが観察されることから診断可能である．