Natural history of branch duct XXXX of the pancreas: a multicenter study in Japan.

@entity1 @entity4929 @entity1124 @entity189 @entity652
OBJECTIVE: The aim of this study was to evaluate the long-term follow-up results of @entity1 with branch duct @entity4929 (BD-IPMNs) without mural nodules (MNs) at 10 representative institutions in Japan. METHODS: We analyzed 349 follow-up BD-IPMN @entity1 who had no MNs on endoscopic ultrasonography at initial diagnosis. RESULTS: Observation periods ranged from 1 to 16.3 years (median, 3.7 years). Sixty-two (17.8%) @entity1 exhibited disease progression during follow-up. Twenty-two underwent surgery, leading to a pathological diagnosis of @entity189 in 9 and @entity652 in 13. Although the remaining 287 (82.2%) showed no changes, 7 underwent surgery because of symptoms (n = 2), choice (n = 2), or development of @entity1124 (n = 3); all of them were diagnosed pathologically as @entity652 . Of the 29 @entity1 undergoing surgery, all 9 with @entity189 exhibited signs of progression, such as increased main pancreatic duct diameter and/or appearance of MNs. @entity1124 and additional BD-IPMNs developed in 7 (2.0%) and 13 (3.7%), respectively. Overall, 320 (91.7%) @entity1 were followed without surgery. CONCLUSIONS: Most BD-IPMN @entity1 who had no MNs on endoscopic ultrasonography could be managed without surgery. However, careful attention should be paid to disease progression and the development of @entity1124 during follow-up.
