Perianal Metastasis of Small Cell Lung Carcinoma: A Case Report

The most common sites for metastasis of lung cancer are the bones, liver, adrenal glands, and brain. Only a few studies have reported on perianal or perirectal metastasis of lung cancer. Herein, we report the case of a 78-year-old man who developed distant perianal metastasis of small cell lung carcinoma (SCLC), presenting as a palpable mass and pain in the buttock, diagnosed through magnetic resonance imaging. Immunohistochemical staining confirmed perianal metastasis from SCLC. It is important to be aware of this uncommon manifestation of lung cancer, which will help in early diagnosis and proper treatment.