Introduction: Metastasis to the gastrointestinal tract from lung cancer is very uncommon and is often asymptomatic. Although small bowel metastasis may commonly occur, metastases to the stomach and colon are uncommon.
Case report: In this paper, we present a previously healthy 57-year-old male patient, a 60-packet per year smoker, who was taken to the emergency room with complaints of increasing abdominal pain, rectal bleeding, weight loss, and dyspnea for the last three months. Endoscopic examination revealed polypoid lesions in the duodenum and the descending colon. We diagnosed neuroendocrine small-cell lung cancer based on histopathological and immunohistochemical staining.Management and outcome: A cisplatin (d1, 60 mg/m2/day)-etoposide (d1 to d3, 120 mg/m2/day) regimen was given every three weeks as palliative chemotherapy. After the three course of chemotherapy, the lung radiograph showed a decline in hilar expansion and there was no pleural effusion. Then, he died of acute respiratory failure two weeks after radiotherapy of brain.
Discussion: Gastrointestinal tract metastasis of lung cancer is recognized synchronously with or rarely before diagnosis. It is generally recognized after the diagnosis of lung cancer. These patients often have other concurrent body metastases. Prognosis is poor, and survival expectation is short. The most common metastases to the gastrointestinal tract are squamous and large cell lung cancer metastases. Our aim is to emphasize the importance of immunohistochemical examination for masses in the gastrointestinal tract and to present this rare case of synchronous duodenal and colonic metastases of small-cell lung cancer.
Keywords: Lung cancer; colonic metastasis; duodenal metastasis; small-cell carcinoma.