Incidence and risk factor of deep venous thrombosis in patients undergoing craniotomy for brain tumors: A Japanese single-center, retrospective study.

•This study first examined post-operative DVT in Japanese brain tumor patients.•DVT occurred in 21.3% after brain tumor resection with mechanical prophylaxis.•About 77% of DVT cases needed no anticoagulant medication.•Infection was an independent risk factor for post-operative DVT.•D-dimer levels during adjuvant therapy were significantly increased in DVT cases.