Background & aims: There is controversy regarding the term biliary intraductal papillary neoplasms (IPN-B) and their pathology, which frequently are confused with hepatic mucinous cystic neoplasms (MCN). We aimed to summarize the clinicopathologic features of IPN-B and differentiate them from MCN.
Methods: From January 1998 to December 2007, there were 19 patients with intrahepatic IPN-B and 13 patients with MCN who underwent surgical treatment at Zhongshan Hospital. Multiple demographic and clinicopathologic parameters were reviewed retrospectively and compared between the groups.
Results: The mean ages of patients with IPN-B and MCN were 59.5 +/- 11.1 and 44.4 +/- 9.7 years, respectively (P = .0004); the male:female ratios also differed (11:8 vs 2:11; P = .028). Tumors were significantly smaller (6.0 vs 11.2 cm; P = .006) in patients with IPN-B than in those with MCN. More patients with IPN-B also had hepatolithiasis (47.4% vs 0%, P = .004); cholangiectasis and communication between the cyst and main bile duct were more frequent in patients with IPN-B than in those with MCN (P < .001). The IPN-B consisted of 4 subtypes--the gastric subtype was the least invasive. Malignant lesions were more common in patients with IPN-B than in those with MCN (78.9% vs 38.5%; P = .03). The overall 5-year survival rates of patients with IPN-B and MCN were 82% and 100%, respectively.
Conclusions: Intrahepatic IPN-B represents a distinct clinicopathologic entity that differs clinically, histologically, and radiologically from MCN. Curative resection has a favorable prognosis for patients with IPN-B, but further studies of its subtype are required.