Small cell lung cancer (SCLC) represents a group of highly malignant tumors that give rise to early and widespread metastases at the time of diagnosis. The preferential metastatic sites are the brain, liver, adrenal glands, bone, and bone marrow. However, metastases of the gastrointestinal system, especially the stomach, are rare; most cases of stomach metastasis are asymptomatic and, as a result, are usually only discovered at autopsy. We report a case of gastric metastasis originating from SCLC. The patient was a 66-year-old man admitted to our hospital due to abdominal pain. He underwent gastroscopy, with the pathological report of the tissue biopsy proving it to be a small cell cancer. Immunohistochemistry was positive for CD56, synaptophysin, and pan-cytokeratin. These results confirmed the diagnosis of gastric metastasis of a neuroendocrine small cell carcinoma from the lung.
Keywords: Gastric metastasis; Immunohistochemistry; Small cell lung cancer.