Intraductal tubulopapillary neoplasms of the bile ducts : Clinicopathologic, immunohistochemical, and molecular analysis of 20 cases

摘要: Intraductal tubulopapillary neoplasm is a well-established entity in the pancreas. A similar, if not identical, tumor occurs also biliary tract. We conducted multicenter study of 20 such lesions, focusing on their clinicopathologic characteristics and molecular profile. Biliary intraductal neoplasms were seen patients 60s (mean 62 years). The tumors intrahepatic 70%, extrahepatic 10%, perihilar 20%; mean size was 6.9 cm. Histologically, all showed, addition to typical tubular pattern, solid areas (70%) or abortive papillae (50%). Necrosis common (85%), predominantly focal (40%), with 'comedocarcinoma-like pattern' 40%. Immunohistochemically, these characterized by expression MUC1 (80%) MUC6 (30%) absence MUC2 MUC5AC. Associated invasive carcinomas present 16 (80%), mainly conventional adenocarcinoma alterations observed included CDKN2A/p16 (intraductal components 44%, 33%) TP53 17%, 9%). Mutations KRAS 6%, 0%), PIK3CA loss SMAD4/DPC4 7%, 0%) rare. No alterations/mutations identified IDH1/2, BRAF, GNAS, EGFR, HER2, β-catenin. Follow-up information available for 17 (85%) follow-up 44 months. Overall combined survival rates showed favorable prognosis: 1 year 100%, 3 years 90%, 5 90%. In conclusion, despite relatively high incidence carcinoma suggests that have an indolent behavior. Molecular analyses highlight low prevalence oncogenic signaling pathways neoplasm. Further studies using whole-exome sequencing are required discover yet unknown changes understand carcinogenesis neoplasms.