Neural or Neural-Related Colorectal Lesion Incidence Varies by Site, and Multifocal Cases Are Often Syndromic: Insights From a Series of 593 Patients.

Abstract

Colorectal lesions with neural differentiation encompass various entities, often presenting with overlapping histologic or immunohistochemical profiles. Most research has focused on single entities, lacking a comprehensive comparative analysis of these lesions. To characterize and compare colorectal lesions with neural differentiation. This study retrospectively examined cases of neural or neural-related colorectal lesions diagnosed between 2004 and 2020 across 2 institutions, analyzing clinical, histologic, and endoscopic features. The cohort included 634 lesions from 593 patients (269 males and 324 females; mean age, 57 years; range, 13-85 years). Most patients were asymptomatic (83%, 490 of 593) and had solitary lesions (92%, 545 of 593), predominantly polypoid or nodular (96%, 610 of 634). Common types included benign fibroblastic polyp/perineurioma (n = 231 of 634, 36%), mucosal Schwann cell hamartoma (n = 203, 32%), and ganglioneuroma (n = 146, 23%), mostly centered in the mucosa (99%, P < .001) of the left colon (n = 318, P < .001). In contrast, granular cell tumors (n = 31, 5%) often involved the submucosa (n = 26, 84%; P < .001) of the cecum and ascending colon (n = 23, 74%; P < .001). Rare lesions like schwannoma (n = 13 of 634, 2%) and neurofibroma (n = 5 of 634, 1%) were found in various sites. A subset of patients (n = 48, 8%) had synchronous and/or metachronous lesions. Of these, 23 (48%) had genetic evidence of a syndromic manifestation (P < .001), with multiple ganglioneuromas in Cowden syndrome (n = 16) being the most common scenario. This is the largest comparative study of neural colorectal lesions, highlighting lesion types' association with colon segments and histologic layers. Multifocal presentations, though rare, are usually linked to genetic syndromes.