[Resection of an Advanced Rectal Gastrointestinal Stromal Tumor Following Neoadjuvant Chemotherapy].

A 66-year-old man was referred to our hospital after being diagnosed with a pelvic tumor. A subsequent transperineal biopsy revealed spindle cells with CD34·c-kit(+). An enhanced computed tomography scan showed a giant rectal-derived tumor in the pelvis. The tumor was pressing on the urinary bladder and the prostate, and appeared to invade the posterior wall ofthese organs. The patient was diagnosed with rectal GIST, and neoadjuvant therapy with 400mg/day imatinib was initiated. Three months later, the tumor reduction rate was at 33.6%, and surgery was performed. The operative method applied was pelvic exenteration and ileal conduit, for local R0 resection. The patient has remained recurrence free for 2.5 years since the surgery.