Late umbilical port-site recurrence of a gastrointestinal stromal tumor with an acquired PDGFRα mutation after laparoscopic resection: report of a case.

A 71-year-old man underwent laparoscopic partial gastrectomy for a gastric submucosal tumor in 1997; subsequently, he underwent follow-up without therapy. In December 2008, he noticed a mass at the umbilical wound. Computed tomography and physical examination of the umbilical mass indicated suspected recurrence of the gastric submucosal tumor at the port site. Because the lesion was locally confined, surgery was performed, including resection of the greater omentum; peritoneum; rectus abdominis; and the navel, including the skin. Histologic analysis of the tumor yielded positive results for c-kit, thereby indicating a gastrointestinal stromal tumor (GIST). Mutation analysis of c-kit and platelet-derived growth factor receptor α (PDGFRα) revealed an acquired mutation in exon 18 of PDGFRα in the recurrent tumor. To date, only 4 cases of port-site recurrence after laparoscopic resection of GIST have been reported. This is the first study to report an acquired PDGFRα mutation in port-site recurrence after laparoscopic resection of a GIST.