A new staging system for mass-forming intrahepatic cholangiocarcinoma - Analysis of preoperative and postoperative variables

BACKGROUND. The objective of this study was to analyze the clinicopathologi c variables and the postoperative outcome in patients with mass-forming int rahepatic cholangiocarcinoma (ICC) to identify important factors for predic ting postresection prognosis. Although it has been reported that mass-formi ng ICC has a different etiology and biologic features compared with hepatoc ellular carcinoma (HCC), patients with ICC have been dealt with clinicopath ologically in the same 2 manner as patients with HCC. METHODS. Sixty patients who underwent hepatectomy for mass-forming ICC with curative intent between 1981 and 1999 were studied. Fourteen preoperative clinical and diagnostic parameters and 12 postoperative surgicopathologic p arameters were analyzed. RESULTS. The rate of operative mortality in this patient cohort was 5%, and the overall 1-year, 3-year, and 5-year survival rates were 68%, 35%, and 2 9%, respectively, with a median survival of 19.6 months. A multivariate ana lysis revealed that independent negative prognostic factors were 1) hepatic regional lymph node metastasis, 2) multiple tumor presentation, 3) symptom atic tumor, and 4) the presence of vascular invasion. Using these factors, a new staging system was devised: Stage I disease was defined as a solitary tumor without vascular invasion, Stage II disease was defined as a solitar y tumor with vascular invasion, Stage IIIA disease was defined as multiple tumors with or without vascular invasion, Stage IIIB disease was defined as any tumor with regional lymph node metastasis, and Stage IV disease was de fined as any tumor with distant metastases. The Kaplan-Meier estimated 3-ye ar survival rate and the median survival for each subgroup were 74% for pat ients with Stage I disease (median survival is the time when the cumulative survival rate of some patients' group declined to 50%; thus, the median su rvival could not be calculated in patients with Stage I disease because sur vival was 74% at the latest follow-up), 48% and 26.2 months for patients wi th Stage II disease, 18% and 16.8 months for patients with Stage IIIA disea se, and 7% and 11.2 months for patients with Stage IIIB disease, respective ly (P < 0.0001). None of the patients met the criteria for Stage IV disease . CONCLUSIONS. The current results support the use of a new staging system fo r patients with ICC that is simple and predicts well the differences in sur vival after patients undergo hepatic resection.