Pathological analysis of collision (double primary) cancer in the upper digestive tract concomitant with gastric stromal tumor: a case report.

Carcinoma of the esophagus and cardiac cancer are common malignancies, while multiple primary cancers in the esophagus and cardia is rarely encountered and easily misdiagnosed. Multiple primary cancers mean the same organs (tissues) or different organs (tissues) have two or more than two primary malignant tumors at the same time or in sequence in the same individual. The case below of two independent primary lesions is double primary carcinoma which meets the diagnosis standard of multiple primary cancers. Gastrointestinal stromal tumor is the most common stromal tumor, which is usually considered as originating from Cajal cells in the gastrointestinal tract or mesenchymal stem cells with the mutation of KIT or PDGFRA gene. Study on stromal tumor with digestive tract cancer is less both at home and abroad, while double primary carcinoma with stromal tumor is rare, which has not been reported at present. Although scholars have different viewpoints on the prognosis, but the full understanding of this disease can be as a warning for the future work and to avoid misdiagnosis.