For cases of inoperable bile duct
carcinoma, we perform intraluminal irradiation using an 192iridium wire following
endoprostheses implantation. However, the effectiveness of this procedure is uncertain, and may lead to decreased patient quality of life in some cases. Therefore, we obtained samples of bile duct
carcinoma either by percutaneous transhepatic cholangioscope (PTCS) or by surgery, and studied whether expression levels of Ki-67 and p53 in these tissues could predict the effectiveness of
radiotherapy (RT). Immunohistochemistry was used to determine the expression of p53 and Ki-67 in 40 resected and 18 biopsy specimens. All biopsy specimens were stage IVA according to UICC classification. Labeling indices were calculated as percentage of positively stained
tumor cell nuclei of total
tumor cells counted. Samples were divided into two groups according to labeling index (LI). In the resected specimens, Ki-67 LI was significantly higher in cases positive for lymphatic invasion than in negative cases (p<0.05), or advanced-stage cases (p<0.05). Also, mean Ki-67 LI was higher in
tumors from cases with
lymph node metastasis than without. In the biopsy specimens, a significant correlation between Ki-67 LI and the term of
stent patency (p<0.05) was observed. However, there were no significant correlations between clinicopathological factors or
stent patency and p53 immunoreactivity. Assessment of mean
Ki-67 antigen expression, as measured by MIB-1 staining, in samples of hilar bile duct
carcinoma appeared to be an important
indicator of clinical behavior. Biopsy specimens obtained by PTCS may be very useful in predicting the effectiveness of RT and assist in the selection of appropriate
therapies.