RT Journal Article SR Electronic T1 Incidental Gallbladder Cancer on Cholecystectomy: Strategy for Re-resection of Presumed Benign Diseases from a Retrospective Multicenter Study by the Yokohama Clinical Oncology Group JF In Vivo JO In Vivo FD International Institute of Anticancer Research SP 1217 OP 1225 DO 10.21873/invivo.12372 VO 35 IS 2 A1 RYUSEI MATSUYAMA A1 KENICHI MATSUO A1 RYUTARO MORI A1 MITSUTAKA SUGITA A1 NAOTAKA YAMAGUCHI A1 TORU KUBOTA A1 KUNIO KAMEDA A1 YASUHISA MOCHIZUKI A1 RYO TAKAGAWA A1 TOSHIAKI KADOKURA A1 GORO MATSUDA A1 NORIYUKI KAMIYA A1 ITARU ENDO YR 2021 UL http://iv.iiarjournals.org/content/35/2/1217.abstract AB Background/Aim: Current expert consensus recommends re-resection for incidental gallbladder cancer (IGBC) of pT1b-3. This study examined whether this consensus was reasonably applicable to patients with IGBC in one Japanese region. Patients and Methods: This was a multicenter, retrospective analysis of cholecystectomies for presumed benign diseases between January 2000 and December 2009. Results: IGBC was diagnosed in 70 (1.0%) out of 6,775 patients undergoing cholecystectomy. Five-year disease-specific cumulative survival was 100% in 19 patients with pT1a, 80.0% in five with pT1b, 49.5% in 33 with pT2, and 23.1% in 13 with pT3. Re-resection was not performed for the 24 patients with pT1a/1b disease, whereas 24 out of 46 patients with pT2/3 underwent re-resection. Regardless of re-resection, independent factors associated with a poor prognosis on multivariate analysis were grade 2 or poorer disease and bile spillage at prior cholecystectomy. In the 24 patients with pT2/3 re-resection, 11 patients without either of these two factors had significantly better 5-year disease-specific cumulative survival than the 13 patients with one or two independent factors associated with a poor prognosis (72.7% vs. 30.8%, p=0.009). Conclusion: This Japanese regional study suggests that indication of re-resection for IGBC should not be determined by pT-factor alone and that much more attention should be paid to pathological and intraoperative findings at prior cholecystectomy.