Colorectal cancer anatomic distribution patterns remain the same after sessile serrated adenoma/polyp considered cancer precursor: a 9-year comparison study from community-based endoscopy centers

Emerging and under-recognised patterns of colorectal carcinoma morphologies: a comprehensive review

While the overwhelming majority of colorectal carcinomas (CRC) are diagnosed as adenocarcinoma not otherwise specified, there are numerous under-recognised morphologic patterns of CRC. These patterns are recognised by the WHO, appear in reporting manuals for the American Joint Committee of Cancer, and/or are listed on synoptic reports, while many other variants have either fallen out of favour or are emerging as future bona fide patterns. Herein, we discuss 13 variants: serrated adenocarcinoma, micropapillary adenocarcinoma, medullary carcinoma, neuroendocrine carcinoma, mucinous adenocarcinoma, signet-ring cell carcinoma, adenosquamous carcinoma, adenoma-like adenocarcinoma, lymphoglandular complex-like CRC, carcinoma with sarcomatoid components, cribriform-comedo-type adenocarcinoma, undifferentiated carcinoma and low-grade tubuloglandular adenocarcinoma. The purpose of this review is to scrutinise these variants by assessing their clinical characteristics, morphologic cues, as well as pitfalls, and address their prognostic significance. Our analysis aims to bring clarity and updated understanding to these variants, offering valuable insights for pathologists. This contributes to more nuanced CRC diagnosis and treatment strategies, highlighting the importance of recognising a broad spectrum of morphologic patterns in CRC.

Three pathologic criteria for reproducible diagnosis of colonic sessile serrated lesion versus hyperplastic polyp

Colonic SSLs are thought to predispose to ∼30% of colonic adenocarcinomas. This increased risk, compared to benign HPs, makes their distinction vitally important. However, no gold standard exists to differentiate them, and wide observer variability is reported. To better distinguish these polyps, we investigated 94 serrated polyps (53 SSLs and 41 HPs) using an easy-to-apply pathologic scoring system that combines, for the first time, three established distinguishing features: polyp morphology, location, and size. As an additional novel approach, polyp size was assessed by serrated biopsy number compared to endoscopic size. RNA expression profiling served as an additional biomarker. The considerable morphologic overlap across serrated polyps was quantitated for the first time. Interobserver variability was assessed by 8 expert gastrointestinal pathologists. By ROC analysis, polyp size by biopsy number performed best, followed by polyp location and morphology (areas under the curves [AUCs] = 85.9%, 81.2%, and 65.9%, respectively). Optimal discrimination combined all 3 features (AUC = 92.9%). For polyp size, the biopsy number proved superior to endoscopic size (AUC = 85.9% versus 55.2%, P = .001). Interobserver variability analysis yielded the highest reported Fleiss and Kappa statistics (0.879) and percent agreement (96.8%), showing great promise toward improved diagnosis. The proposed 3-criteria pathologic system, combining size by biopsy number, location, and morphology, yields an improved, easy-to-use, and highly reproducible diagnostic approach for differentiating SSLs and HPs.

Peroral-cholangioscopy to plan surgery for protruding biliary lesions: report of four cases

Intraductal biliary lesions can involve the main hepatic confluence. Assessment of the extension of pedunculated biliary lesions during per-oral cholangioscopy (POCS) can optimize and personalize the surgical strategy. Four consecutive cases of pedunculated biliary lesions were analysed. Cholangioscopy was performed with a disposable single-operator cholangioscope. POSC was successfully performed in four patients (three female, mean age 50 years), showing involvement of the main biliary confluence in three of four pedunculated biliary lesions; direct biopsy sampling was diagnostic in two of three cases (in one patient, biopsy were not performed due to the smooth appearance of the intrabiliary lesion). No adverse events occurred after POCS. Surgery required excision of the main hepatic confluence in two of three cases (one patient was not resectable). POCS can diagnose intrabiliary extension of protruding biliary lesions, providing important information to plan the surgical intervention.

Acceptability of endoscopic submucosal dissection for sessile serrated lesions: comparison with non-sessile serrated lesions

Background and study aims  Sessile serrated lesions (SSL) are major precursor lesions of serrated pathway cancers, and appropriate treatment may prevent interval colorectal cancer. Studies have reported the outcomes of endoscopic mucosal resection (EMR) for SSL; however, there are insufficient reports on endoscopic submucosal dissection (ESD). We examined the characteristics and outcomes of SSL and compared them to those of non-SSL in ESD. Patients and methods  We reviewed 370 consecutive cases in 322 patients who underwent colorectal ESD between January 2016 and March 2020 at our hospital. There were 267 0-IIa lesions that were stratified into 41 SSL and 226 non-SSL (intramucosal cancer, adenoma) cases. We used propensity matching to adjust for the variances in the factors affecting treatment between the SSL and non-SSL groups. Results  In the baseline cases, young women and proximal colon tumor location were significantly more common in the SSL group. There were no statistically significant differences between the SSL and non-SSL groups in terms of en bloc resection rate (97.6 % vs. 99.6 %; P  = 0.28), R0 resection rate (92.7 % vs. 93.4 %; P  = 0.74), perforation (0 % vs. 0.9 %; P  > 0.99), and postoperative bleeding (2.4 % vs. 1.8 %; P  = 0.56). Thirty-eight pairs were matched using propensity score, and the median dissection speed (12 vs. 7.7 cm ² /h; P  = 0.0095) was significantly faster in the SSL than in the non-SSL group. Conclusions  ESD for SSL was safely performed, and SSL was smoother to remove than non-SSL. ESD might be an acceptable endoscopic treatment option for SSL.

Surgical and postoperative evaluations of rectal adenomas excised with a rigid proctoscope

PURPOSE

This study presents the surgical and postoperative results achieved with a rigid proctoscope using the transanal endoscopic technique to excise rectal adenomas. The results are compared to the results obtained with other currently employed transanal techniques.

METHODS

We investigated the medical records of patients who underwent transanal endoscopic operations from April 2000 to June 2018 at two tertiary referral centers for colorectal cancer.

RESULTS

This study included 99 patients. The mean age was 65.3 ± 13.3 years. The average size of the adenomas was 4.6 ± 2.3 cm, and their average distance to the anal border was 5.6 ± 3.3 cm. The average operative time was 65.3 ± 41.7 min. In 48.5% of the operations, the specimen was fragmented, and in 59.6% of the cases, the microscopic margins were free. The rates of postoperative complications and relapse were 5% and 19%, respectively. The mean follow-up was 80 ± 61.5 months.

CONCLUSIONS

The described proctoscope proved to be a viable technique with results similar to other techniques, with the advantage that it allowed greater accessibility for surgeons. Therefore, its use could be implemented and become widespread in surgical practice.