Artificial Intelligence Allows Leaving-In-Situ Colorectal Polyps.

BACKGROUND & AIMS: Artificial Intelligence (AI) could support cost-saving strategies for colonoscopy because of its accuracy in the optical diagnosis of colorectal polyps. However, AI must meet predefined criteria to be implemented in clinical settings. METHODS: An approved computer-aided diagnosis (CADx) module for differentiating between adenoma and nonadenoma in unmagnified white-light colonoscopy was used in a consecutive series of colonoscopies. For each polyp, CADx output and subsequent endoscopist diagnosis with advanced imaging were matched against the histology gold standard. The primary outcome was the negative predictive value (NPV) of CADx for adenomatous histology for ≤5-mm rectosigmoid lesions. We also calculated the NPV for AI-assisted endoscopist predictions, and agreement between CADx and histology-based postpolypectomy surveillance intervals according to European and American guidelines. RESULTS: Overall, 544 polyps were removed in 162 patients, of which 295 (54.2%) were ≤5-mm rectosigmoid histologically verified lesions. CADx diagnosis was feasible in 291 of 295 (98.6%), and the NPV for ≤5-mm rectosigmoid lesions was 97.6% (95% CI, 94.1%-99.1%). There were 242 of 295 (82%) lesions that were amenable for a leave-in-situ strategy. Based on CADx output, 212 of 544 (39%) would be amenable to a resect-and-discard strategy, resulting in a 95.6% (95% CI, 90.8%-98.0%) and 95.9% (95% CI, 89.8%-98.4%) agreement between CADx- and histology-based surveillance intervals according to European and American guidelines, respectively. A similar NPV (97.6%; 95% CI, 94.8%-99.1%) for ≤5-mm rectosigmoids was achieved by AI-assisted endoscopists assessing polyps with electronic chromoendoscopy, with a CADx-concordant diagnosis in 97.2% of cases. CONCLUSIONS: In this study, CADx without advanced imaging exceeded the benchmarks required for optical diagnosis of colorectal polyps. CADx could help implement cost-saving strategies in colonoscopy by reducing the burden of polypectomy and/or pathology. CLINICALTRIALS: gov registration number: NCT04884581.

A rare case of metachronous neuroendocrine tumor after a colorectal adenocarcinoma: qualitative critical review of synchronous and metachronous gastrointestinal NET.

Gastrointestinal neuroendocrine tumor (NET) associated with a metachronous intestinal adenocarcinoma is rare. We report the case of a 71-year-old man with an ileal NET. Patient has previously undergone a left colectomy for sigmoid cancer. We report a complete review both of the metachronous and synchronous NET. A comprehensive systematic literature search in PubMed, EMBASE, and MEDLINE identified a total of 35 relevant studies. This study includes an analysis of review articles, case reports, case series, retrospective studies and population-based studies. In the English literature to date, there are 21 case reports (19 synchronous cases and 2 metachronous cases), 3 case series and 3 review articles, and less than 10 retrospective studies or population-based studies. A total of 31 patients in 24 articles were included in the study: 28 patients with a synchronous gastrointestinal NET and colorectal adenocarcinoma and 3 patients with metachronous gastrointestinal NET and colorectal adenocarcinoma. The incidence of synchronous cancer (particularly for colorectal and gastric cancer) with a gastrointestinal NET ranges from 10 to 50%, while for the metachronous ones it is still unclear. This is the third metachronous case report and the first descriptive case of gastrointestinal NET diagnosed 2 years after a colorectal adenocarcinoma. An endoscopic follow-up program for gastrointestinal NET patients and/or for first-degree relatives of NET patients appears recommendable.

A very unusual cause of dysphagia: mantle cell lymphoma.

Dysphagia is an alarm symptom requiring a prompt investigation. Different benign and malignant diseases may present such a symptom. We describe a case of a 79-year-old patient who complained of fluctuating dysphagia episodes following solid food ingestion in the previous 5 months with mild weight loss. No other gastrointestinal symptoms were present. The patient was referred by the General Practitioner for a videofluoroscopic swallow examination which revealed nodularity of mucosa surface in the oropharynx, esophagus, fundus, and gastric body. Upper endoscopy confirmed the feature, also showing a normal mucosa of the antrum and duodenum. The histological examination revealed a mantle cell lymphoma (MCL). A stage III, MCL involving the esophagus and proximal stomach was eventually diagnosed. Esophageal MCL localization is extremely rare, and this is the first report showing a clinical onset with dysphagia.

Gastric metastases from gynaecologic tumors: case reports and review of the literature.

The stomach is an infrequent localization of tumor metastases, and metastases originating from primary gynaecological cancers are particularly rare. We described the case of three females with ovarian, uterine, and breast metastases in the stomach, and we performed a systematic review of the literature of cases diagnosed at endoscopy. Overall, data of 18 patients with gastric metastases originating from the ovary, 11 from the uterus, and 159 from breast cancer were analyzed. Therefore, gastric metastasis mainly occurs from breast cancer, whilst both ovarian and uterine metastases are distinctly less frequent, but not impossible.