Primary lung squamous cell carcinoma with gastric metastasis: A case report.

Approximately 50% of patients with primary lung cancer have distant metastasis at the time of their first visit, but gastric metastasis is a rare occurrence. Herein, we report a case of progressive dysphagia as the first symptom and the final diagnosis of primary lung squamous cell carcinoma metastasis. A 61-year-old man was diagnosed with a solitary left lower lobe tumor and a solitary carcinoma of gastric cardia suspected to be metastatic or malignant stromal tumors. After surgical resection, the final diagnoses were primary differentiated squamous cell lung cancer, metastatic squamous cell carcinoma of the stomach, and secondary lymph node metastasis. Gastrointestinal metastasis should be suspected in lung cancer patients with gastrointestinal symptoms. Gastric cancer metastasis from lung cancer is most likely the result of the aspiration of cancer cells containing sputum into the stomach.