Duodenal Metastasis From Primary Lung Adenocarcinoma: A Diagnostic and Therapeutic Challenge

Distant metastasis from primary lung cancer is mostly seen in the liver, brain, adrenal glands and bones. Small bowel, specifically duodenum is a relatively unusual site for distant metastasis from lung carcinoma. This case reports a rare scenario of upper gastrointestinal bleeding caused by duodenal metastasis by a primary lung adenocarcinoma. A 43-year-old woman presented to the emergency department with complaints of progressive hemoptysis for the past three weeks. Esophagogastroduodenoscopy (EGD) revealed a 2.5 cm x 2.5 cm fungating villous mass-like structure in the first portion of the duodenum, with a normal-appearing esophagus and stomach. Biopsies were performed, which were histologically consistent with poorly differentiated malignant. The immunohistochemical (IHC) staining was consistent with metastatic disease from primary lung adenocarcinoma. Due to its rarity, there are no solidified guidelines for the management of duodenal metastasis from lung carcinoma. Our case was challenging due to the extensive metastasis and low functional status of the patient and was ultimately managed with home hospice.