[A Case of Lower Rectal GIST with Anorectal Preservation by Laparoscopic Low Anterior Resection after Imatinib Mesylate Neoadjuvant Therapy].

A 60-year-old man was diagnosed with a rectal gastrointestinal stromal tumor(GIST). Endoscopy revealed a submucosal tumor in the lower rectum near the dentate line. CT and MRI findings showed that the tumor was compressing the prostate and seminal vesicles. To shrink the tumor whilst preserving the anus, 400 mg/day of imatinib mesylate (IM)was administered as preoperative drug therapy. Six months after the initiation of neoadjuvant therapy, the patient underwent laparoscopic low anterior resection of the rectum. Postoperatively, IM was resumed as adjuvant therapy, but was discontinued after 10 months due to the occurrence of side effects. No recurrence of the tumor was observed during a 2 years and 3 months postoperative assessment. We believe that preoperative pharmacotherapy with IM is an effective treatment strategy. Herein, we report the details of this case along with a review of the literature.