2005 Volume 38 Issue 8 Pages 1369-1373
We report a case of peritoneal dissemination due to gastrointestinal stromal tumor (GIST) recurring almost 2 years postoperatively. The condition responded very favorably to treatment involving imatinib mesylate, after other therapy including 2 resections of peritoneally disseminated tumors, conventional immunochemotherapy, and continuous hyperthermic peritoneal perfusion (CHPP), proved ineffective. A 55-year-old man undergoing resection of the small intestine due to a 13cm giant ileal tumor 6 years earlier found histologically to consist of a fascicular proliferation of spindle-shaped cells with marked mitosis immunohistochemically positive for c-kit and the finally diagnosed with malignant GIST, was hospitalized 2 years later for lower abdominal pain and slight fever. Abdominal computed tomography (CT) showed multiple intraabdominal abscesses which finally diagnosed as peritoneal dissemination of GIST, necessitating 2 tumor resections. CHPP and intraabdominal infusion of CDDP at the second reduction surgery, conventional ADIC chemotherapy, and Krestin immunotherapy proved ineffective against the recurrent tumor. In Feb. 2002, oral administration of imatinib mesylate at 400mg/day was started. An abdominal CT showed rapid tumor disappearance. Response to treatment has continued up to the 30 months as of this writing. Drug toxicity resulting in facial edema and appetite loss were mild and tolerable. Our results strongly suggest that imatinib mesylate is potentially very effective and safe in treating recurrence of malignant GIST.
