Collision tumor of the esophagus: report of a case with mixed squamous cell carcinoma and gastrointestinal stromal tumor.
The synchronous existence of two different tumors in the gastrointestinal tract is uncommon. We report the case of a 75-year-old man who had a concurrent gastrointestinal stromal tumor and adenocarcinoma at the gastroesophageal junction. The two tumors arose at the same site but had distinct morphologies. The etiology of synchronous tumors is still unclear and their coexistence causes problems for the surgeon, oncologist and pathologist in terms of their diagnosis, treatment, and follow-up. We report a rare case of synchronous tumors and a review of the literature.