Is the Primary Tumor Site of Ampullary Carcinoma Distinct in the Setting of Morphology Subtype?

Abstract

Introduction/Objective Ampullary cancer (AC) are rare and represents only 6% of the malignant periampullary tumors. Two main histologic subtypes of AC are pancreatobiliary (Pb-AC), and intestinal (In-AC). The data on the influencing role of several characteristics associated with AC subtypes on long term outcome is still emerging. Our study aimed to analyze the two subtypes Pb-AC and In-AC regarding their primary tumor site, median overall survival, and associated precursor lesion. Methods/Case Report Using the cBioPortal platform and systematic bioinformatical analysis of the Cancer Genome Atlas Baylor College of Medicine Cell Reports, 2016, 133 AC patients were included and analyzed based on their morphology subtype. Of which 62 patients had the intestinal subtype, and 71 had the pancreaticobiliary morphological subtype. Results (if a Case Study enter NA) The role of primary tumor site was statistically significant (p-value = 0.01) among subtypes Pb-AC and In-AC (See Figure). Remarkably, the primary tumor site most associated with the pancreaticobiliary subtype was the distal bile duct, and the intestinal subtype was intra-ampullary. Additionally, the precursor lesion identification (absent vs present) was statistically significant among the subtypes (p-value = 0.01). Further, the median overall survival in ampullary carcinoma varied among the morphology of the two subtypes: In-AC (75.56 months, (95% CI: 57.04-NA)) and Pb-AC (27.04 months, (95% CI: 18.29-NA)). Conclusion The findings in this study highlight the complex multifactorial role of the two morphological subtypes in AC. Further studies are essential for understanding the underlying tumor site specific molecular signatures leading to subtyping and their impact on prognosis.