加藤 直也

Although some studies have compared the treatment outcomes between modified endoscopic mucosal resection (m-EMR) and endoscopic submucosal dissection (ESD) for rectal neuroendocrine tumors (NETs), the results are based on the experience of experts from a single high-volume center. This multicenter study aimed to compare the outcomes between m-EMR and ESD for rectal NETs, with emphasis on the operator's level. Data of patients with rectal NETs treated using m-EMR or ESD at seven institutions that included general hospitals in Japan were retrospectively reviewed. Patients treated using m-EMR and those treated using ESD were matched for age, sex, lesion size, lesion location, and operator level through propensity score matching. The treatment outcomes were compared between the two groups. In total 304 patients (m-EMR = 178, ESD = 126) were included, with 218 in the matched groups (m-EMR = 109, ESD = 109). The R0 resection rate was not significantly different between the two groups (90.0% vs. 82.3%, P = .221). However, the procedural time was significantly shorter for the m-EMR group than that for the ESD group (6 vs. 26 min, P < .001). No significant difference in adverse events was observed between the two groups (postprocedure bleeding rate: 5.5% vs. 2.8%, P = .335; perforation rate: 0.9% vs. 0.9%, P = 1.00). Subgroup analysis revealed that the R0 resection rate for the trainees was significantly higher in the m-EMR group than in the ESD group (87.9% vs. 64.5%, P = .017). m-EMR is the preferred technique for the treatment of rectal NETs and should be considered, particularly for the trainees.

BACKGROUND: Pit pattern diagnosis using crystal violet staining for colorectal tumors is useful for qualitative and depth diagnosis. However, due to its reported carcinogenic potential, the use of crystal violet has been restricted. This study was aimed at investigating the efficacy of texture and color enhancement imaging (TXI) magnification in pit pattern diagnosis. METHODS: This study enrolled consecutive patients with consent obtained and with colonic tumors indicated for magnifying endoscopy in which all modalities' images (magnified observation with crystal violet staining (CV), magnified white light observation with indigo carmine (IC-WLI), and magnified TXI observation with indigo carmine (IC-TXI)) were evaluable between July 2020 and January 2023. The visibility of the pit pattern using a 5-point Likert scale and its diagnostic accuracy were compared (IC-TXI vs. IC-WLI, reference: CV, by three experts). RESULTS: A total of 145 colorectal tumors from 145 patients were included. Visibility scores for the pit pattern were significantly higher with IC-TXI compared to IC-WLI (all three experts, p < 0.0001). The pit pattern match rate (Type II/III/IV/V) of IC-TXI compared to CV was also superior to IC-WLI (72.9% vs. 59.7%; p = 0.02). CONCLUSIONS: IC-TXI provided reasonably good and higher visibility and diagnostic accuracy than IC-WLI for pit pattern diagnosis of colorectal tumors compared to CV, suggesting it as an alternative to CV.