Purpose: The feasibility of defining early cholangiocarcinoma has not been adequately evaluated. The surgical outcomes of patients who had undergone pancreatoduodenectomy (PD) for pathological T1 (pT1) distal cholangiocarcinoma (DCC) were evaluated to determine whether it is possible to define early DCC.
Methods: The clinicopathological data of 18 patients with pT1 DCC who had undergone PD were reviewed retrospectively. Depth of fibromuscular (fm) layer invasion was divided into two categories: fm1 and fm2 (without adventitia fascia invasion and with adventitia fascia invasion). Comparative analyses were performed according to the depth of invasion.
Results: Disease-specific survival rates of patients with five mucosal tumors and 13 fm-invasive tumors were 80 and 61.9 % at 5 years and 80 and 41.2 % at 10 years, respectively. There was no significant difference in disease-specific survival rates between the two groups (P = 0.244). Disease-specific survival rates of patients with 7 fm1-invasive tumors and 6 fm2-invasive tumors were 85.7 and 40 % at 5 years and 85.7 and 0 % at 10 years. A significant difference in disease-specific survival rates was observed between mucosal tumors and fm2-invasive tumors (P = 0.043), and disease-specific survival rates of mucosal tumors and fm1-invasive tumors were similar (P = 0.968).
Conclusions: Defining early DCC as carcinoma confined to the fm of the bile duct might be inappropriate; early DCC should be limited to the mucosal carcinoma.
Keywords: Distal cholangiocarcinoma; Early cancer.