Carcinoma of the lung with metastases to skeletal muscles

A prominent feature of the natural history of carcinoma of the lung is that it invariably metastasizes to other organs. The well-known sites include lymph nodes, liver, adrenals, bones and brain. Spread is mainly by lymphatic and haematogenous routes, or by direct extension. However, like many other primary malignancies, the spread of carcinoma of the lung to skeletal muscles is rare. This is despite its bulk and abundant blood supply. Why this is so is unknown. A search of the literature revealed only 3 published case reports of carcinoma of the lung spreading to skeletal muscles. In this paper, we report a case of squamous cell carcinoma of the lung with multiple metastases to skeletal muscles.