Synchronous Occurrence of Gastric Signet Ring Cell Carcinoma and Pulmonary Fibrosarcoma in 23-Year-Old Male Youth.

The synchronous occurrence of epithelial-derived gastric signet ring cell carcinoma and mesenchymal-derived pulmonary fibrosarcoma in a single patient is extremely rare in clinical practice. Here, we report the case of a 23-year-old man who presented with hematemesis and melena for 6 days. Gastroscopy revealed two irregular small ulcers in the upper-middle segment of the gastric body. CT imaging demonstrated uneven thickening of the gastric wall along the greater curvature, with local ulcer formation, as well as a small nodule in the left lower lobe of the lung. The patient underwent thoracotomy, and postoperative pathology confirmed signet ring cell carcinoma in the stomach and fibrosarcoma in the lung. The coexisting tumor was diagnosed in one patient although it is unknown whether it is an accidental event or is caused by some underlying mechanism that makes him develop different malignancy in different organs simultaneously. This report serves to alert clinicians to this rare condition.