A Case of Concomitant Small Bowel GIST and Colorectal Cancer Treated by Simultaneous Laparoscopic Resection

[Abstract] This report documents simultaneous laparoscopic resection of a small bowel gastrointestinal stromal tumor (GIST) and transverse colon cancer that were diagnosed preoperatively and concomitantly. The patient was an 88-year-old man who was referred to us when computed tomography (CT) performed as follow-up for prostate cancer revealed what appeared to be a small bowel tumor. Abnormal tracer uptake in the small bowel and transverse colon was observed on FDG-positron emission tomography/CT images, so we performed lower gastrointestinal endoscopy and discovered a type 2 transverse colon cancer. Laparoscopic partial colectomy and partial small bowel resection were performed for a pathological lesion suspected of being GIST, following which a definitive histopathological diagnosis of transverse colon cancer and small bowel GIST were confirmed. Although GIST can be complicated by other malignant tumors, complication by colorectal cancer is uncommon. A literature search revealed only 8 patients who had undergone simultaneous resection for small bowel GIST and colorectal cancer, and 5 of the 8 were treated by open surgery. There are scattered reports indicating that, as in our case, laparoscopy was performed. We present a rare case of concomitant small bowel laparoscopic resection and review the relevant literature.