Small bowel metastases from primary lung carcinoma: a rarity waiting to be found?

Isolated, small bowel metastases from lung carcinoma are extremely rare; only 34 cases have been previously reported. Rarer still is the presentation of lung carcinoma with a lesion metastatic to the small bowel. These 34 cases and 3 recent ones from Easton Hospital (Easton, PA) were analyzed to clarify the clinical and pathologic features of the disease. The majority of patients had a history of abdominal pain (86%), melena (23%), or nausea and vomiting (26%). Few had weight loss (16%). Twenty-one patients (57%) came to the hospital with perforation and peritonitis, including 9 in whom lung carcinoma was undiagnosed before laparotomy. Thirteen patients (34%) underwent laparotomy because of small bowel obstruction, 2 (6%) for bleeding and 1 (3%) for a mass found during work-up. Squamous cell (49%) and large cell (22%) were the most common cell types, and the jejunum was the most common site of the metastases (79%). Survival time was dismal (mean 51 days) and was unaffected by therapy to the primary site of the cancer or its metastases. The authors conclude that small bowel metastases from lung carcinoma are not uncommon and may be seen more frequently as patients live longer after their diagnosis of cancer. Small bowel metastases must be considered in any patient with both lung carcinoma and abdominal pain, and should be expected in patients with both lung carcinoma and an acute abdomen.