[Histological factors predicting loco-regional lymph node metastasis in early invasive colorectal adenocarcinoma pT1]

Abstract

Introduction: Endoscopic resection is the common treatment in pT1 colorectal adenocarcinoma whenever possible. The presence of adverse histological factors requires subsequent lymph node evaluation.

Materials and methods: We selected 29 colorectal pT1 adenocarcinoma including endoscopic polypectomies and the corresponding surgical specimens. All histologic parameters associated with N+ were evaluated by 2 pathologists, including: tumor differentiation grade, depth of invasion in the submucosa, angiolymphatic invasion (ALI), perineural invasion, chronic inflammation, tumor budding, poorly differentiated cluster, pre-existing adenoma, tumor border, and endoscopic resection margin. Univariate and multivariate logistic regression analysis were performed to assess the individual capacity of each variable to predict N+.

Results: In the univariate analysis, rectal tumor localization, ALI and poorly differentiated cluster was significantly associated with N+. Among the significant parameters, ALI had the highest area under the ROC curve (0.875). Multivariate analysis showed no independent variables associated with N+.

Conclusions: We confirm that ALI and the presence of poorly differentiated cluster are frequently associated with N+ in early colorectal cancer. Consequently, these parameters should be routinely evaluated by pathologists.

Keywords: Adenocarcinoma pT1; Colorectal cancer; Cáncer colorrectal; Grupos de tumor pobremente diferenciados; Poorly differentiated clusters; pT1 adenocarcinomas.