COMPARISON OF CLINICAL PARAMETERS AND PATHOLOGICAL FEATURES OF INTESTINAL AND PANCREATOBILIARY HISTOLOGIC PHENOTYPES OF PERIAMPULLARY CARCINOMA

Abstract

Background: Identification of the exact origin in large sized tumors of periampullary region is very difficult grossly and microscopically. The purpose of the study was to compare the two histological phenotypes of periampullary carcinoma in terms of their preoperative clinical parameters and pathological features.

Methods: This was a prospective observational study done in patients diagnosed as periampullary carcinoma in specimen after pancreatoduodenectomy, between May 2018 and July 2019 at a Tertiary Teaching Hospital of Nepal. Relevant patient clinical characteristics, biochemical parameters including CEA and CA 19.9, immuno-histochemical markers (CK-20 and MUC-1) expression and histopathological details were recorded. Student t-test, ANOVA, median test, Kruskal Wallis test, binary logistic regression tests were used for analysis in SPSS version 20. P-value < 0.05 was considered significant.

Results: Thirty-nine patients with periampullary adenocarcinoma in Pancreatoduodenectomy specimen were included in the study with mean age of 58.6 years. Ampullary tumors (53.8%) were common in this study. Pancreatobiliary phenotype (61.5% versus 38.5%), was more common in head of pancreas and distal CBD tumors and was associated with significantly higher lymph node ratio (0.174 ± 0.173 versus 0.069±0.096), higher rates of lymphovascular invasion (66.7% versus 33.3%) and perineural invasion (75% versus 26.7%) on univariate analysis. On multivariate analysis, Perineural invasion was associated with Pancreatobiliary phenotype (Odds ratio of 10.46).

Conclusions: Pancreatobiliary phenotype of periampullary tumors was associated with poor prognostic pathologic features like high lymph node ratio, lymphovascular invasion and perineural invasion. Perineural invasion had the strongest association of all.