Muscular metastasis, a rare presentation of non-small-cell lung cancer

A 71-year-old man presented with a 2-week history of pain and swelling of his left arm. Subsequent investigations revealed an intramuscular lesion, suggestive of soft tissue sarcoma. Histologic analysis was surprisingly consistent with metastasis from a primary squamous cell lung cancer. Skeletal muscle metastasis as a mode of presentation of primary lung cancer is an unusual phenomenon. A brief literature review accompanies this report.