Non-small cell lung cancer with gastric metastasis and repeated gastrointestinal bleeding: A rare case report and literature review.

The occurrence of gastrointestinal metastasis from lung carcinoma is rare. Compared with non-small cell lung cancer (NSCLC), small cell lung cancer more commonly results in this sort of metastasis. Here, we report an unusual case of NSCLC initially without evidence of distant metastasis that developed into gastric metastasis five months after the initial diagnosis, despite the primary lung cancer having a partial response to radiotherapy and chemotherapy. Serial radiological examinations and endoscopic biopsies of the gastric tumor confirmed that it was a metastatic carcinoma originating from the lung. The patient received a total gastrectomy for gastric metastasis due to repeated gastrointestinal bleeding.