Surgical Outcomes of the Mass‐Forming plus Periductal Infiltrating Types of Intrahepatic Cholangiocarcinoma: A Comparative Study with the Typical Mass‐Forming Type of Intrahepatic Cholangiocarcinoma

BACKGROUND: The purpose of this study was to clarify the clinicopathologic characteristics and surgical outcomes of patients with the mass-forming (MF) plus periductal infiltrating (PI) type of intrahepatic cholangiocellular carcinoma (ICC). METHODS: Between January 1, 1998, and December 31, 2004, a total of 94 patients with ICC underwent macroscopic curative resection, and the macroscopic type of the tumors was assessed prospectively. Among the 74 patients with the MF type (n = 46) and the MF plus PI type (n = 28) of ICC, multivariate analysis was conducted to identify the potential prognostic factors. The clinicopathologic data of the two groups were compared. RESULTS: The results revealed two independent prognostic factors: presence/absence of intrahepatic metastasis and the macroscopic type of the tumor. ICCs categorized macroscopically as the MF plus PI type were significantly associated with jaundice (p < 0.001), bile duct invasion (p < 0.001), portal vein invasion (p = 0.025), lymph node involvement (p = 0.017), and positive surgical margin (p = 0.038). CONCLUSION: Identification of the macroscopic type of the tumor is useful for predicting survival after hepatectomy in patients with ICC. The MF plus PI type of ICC appears to have a more unfavorable prognosis, even after radical surgery, than the MF type of ICC.