Case Report: Synchronous primary location of gastrointestinal stromal tumors (GIST) and adenocarcinoma of the colon: an unusual occurrence.

Background: We have little knowledge about the synchronous occurrence of gastrointestinal stromal tumors (GISTs) and other types of histologic tumors. This association is very rare. Case presentation: We describe a case of synchronous stromal tumor and adenocarcinoma of the left side colonic localization. Immunohistochemistry identified c-Kit expression. The discovery of colonic adenocarcinoma was on operative specimen after histologic examination. The patient underwent left oncologic colectomy with stoma. Follow-up at one year postoperatively did not detect tumor recurrence. Discussion: Clinical implications of the association between these two neoplasms are not clearly described. Treatment depends on the the most aggressive histologic type or obviously highest stage. Knowledge of the genetic data of this association offers opportunity of treatment with the new targeted-therapy molecules. Surgical resection, may remain the curative treatment. Conclusions: Synchronous adenocarcinoma and GIST has been more commonly described in the stomach.  The pathogeneses of tumorigenesis may not be the same for the two tumors. More studies seem be necessary to clarify a potential role of different genes in the development of adenocarcinomas. And therefore, above all their therapeutic implications.