Watanabe Y, Matsuyama Y, Izumi N, et al. - Researchers here examined how surgical margin width affects patients undergoing R0 resection for intrahepatic cholangiocarcinoma, using the database of a Japanese nationwide survey. They assessed data of 635 patients with intrahepatic cholangiocarcinoma who were treated by an R0 resection from 2000 to 2007 and divided them into quartiles of the surgical margin width as follows: marginal (< 1 mm), narrow (1–4 mm), intermediate (5–9 mm), and wide groups (≥ 10 mm). Outcomes suggest only a limited effect of surgical margin width on the prognosis of intrahepatic cholangiocarcinoma except in cases without lymph node metastasis, where a wide surgical margin is linked with favorable outcomes. Especially the mass-forming type intrahepatic cholangiocarcinoma apparently exhibited this survival benefit of a wide surgical margin.