Impact of Macroscopic Morphology, Multifocality, and Mucin Secretion on Survival Outcome of Intraductal Papillary Neoplasm of the Bile Duct

Background: Intraductal papillary neoplasms of the bile duct (IPNB) are relatively rare disease with favorable prognosis. The authors investigated clinicopathologic characteristics and prognostic factors of IPNB in viewpoint of macroscopic morphology and multiplicity. Methods: Data were collected from 84 patients who underwent surgery at Seoul National University Hospital with diagnosis of IPNB from 2000 to 2009. Results: Median follow-up was 41. 8 months and 75 (89. 3 %) had invasive cancer. Tumors were confined to the bile duct in 45 patients (53. 6 %) and 8 (9. 5 %) had lymph node metastasis. Curative resection was achieved in 70 patients (89. 3 %). Mucin secretion was identified in 23 (28. 0 %) and 43 (51. 2 %) had multiple tumors. Multiple IPNB had poor prognosis compared with single IPNB (5-year survival rate 50. 7 vs. 85. 9 %; P = 0. 011). Positive resection margin (P = 0. 046) and multiplicity (P = 0. 038) were independent prognostic factors of IPNB after multivariate analysis. Mucin secretion had no impact on survival outcome (P = 0. 595). The disease-free survival rate was significantly lower in multiple IPNB compared with single IPNB (5-year disease free survival rates 36. 1 vs. 74. 1 %; P = 0. 026). Conclusion: Multiplicity is a common feature of IPNB and has a negative impact on prognosis. Current WHO classification for IPNB needs consideration for macroscopic morphology and multiplicity considering its prognostic impact of IPNB.