Prognostic value of cell proliferation (Ki-67 antigen) and nuclear DNA content in clinically resectable, distal bile duct carcinoma

Background: The aim of this study was to investigate the prognostic value o f cell proliferation (Ki-67 antigen) and DNA content in patients resected f or distal bile duct carcinoma (DBDC). Methods: Formalin-fixed tumor specimens of 35 patients with resected DBDC a nd a long-term clinical follow-up were analyzed. MIB-1 antibody was used fo r Ki-67 antigen detection to determine the proportion of proliferating cell s. DNA content was measured using flow cytometry. Results: A significant correlation was found between a low MIB-1 index (<20 %) and survival (P <.05). Of the 35 tumor specimens, 34 specimens were eval uable by flow cytometry: 22 carcinomas were diploid (65%), and 12 were aneu ploid (35%). The median DNA index of aneuploid tumors was 1.36 (range, 1.09 to 1.76). No correlation of DNA-ploidy with survival time was found. Conclusion: In contrast to DNA-ploidy pattern, Ki-67 antigen expression sho wed prognostic significance in resectable DBDC. A Ki-67 positive ratio of g reater than or equal to 20% was associated with decreased survival time.