Metastatic squamous cell carcinoma of the lung masquerading as a soft tissue tumor

Carcinoma of lung can metastasize to any organ system; however, metastasis to skeletal muscles is extremely rare. A 63-year-old man, known case of pulmonary tuberculosis on treatment, presented with a painful swelling in his left leg. Examination revealed a 5.0 cm × 3.0 cm calf swelling, which on imaging was suggestive of a soft tissue tumor. Fine-needle aspiration cytology of the swelling revealed it to be squamous cell carcinoma. Further investigations revealed a mass in the left lower lobe of the lung. Biopsies from both the lung lesion and calf swelling confirmed the diagnosis of squamous cell carcinoma of lung with metastasis to the calf muscle. The case is being presented because of its unusual presentation and rarity.