Muscle metastasis as initial manifestation of epidermoid carcinoma of the lung

Typical sites of squamous cell carcinoma of lung metastases include liver, brain, bones, pulmonary and adrenal glands. In advanced dissemination it can rarely involve the skeletal muscle. The patient in this case report was a 46-year-old man, with no significant medical history. He was admitted to hospital because of a large swelling on his left thigh. Investigations resulted in a diagnosis of primary squamous cell carcinoma of the lung. Biopsy of the left great adductor muscle produced similar pathology to that of the lung primary. This case report describes a skeletal muscle metastasis as the first sign of metastatic disease.