Pedunculated Pulmonary Parenchymal Leiomyoma Associated with Hypertrophic Osteoarthropathy: Case Report

Hypertrophic osteoarthropathy, a condition of osteitis of the long bones that manifests clinically with clubbing, is often secondary to a thoracic neoplasm, especially lung carcinoma in long-time smokers. We report an unusual case in which hypertrophic osteoarthropathy was the only manifestation of a benign pulmonary parenchymal leiomyoma. A 38- year-old non-smoking man had bilateral clubbing of the fingers. Hypertrophic osteoarthropathy was diagnosed when radiography revealed thin lamellar deposits along the metatarsals and phalanges of the hands and similar osteal changes in the feet. Respiratory tests indicated normal lung functioning, but computed tomography revealed a 5x4 cm2 lobulated mass in the lower left lung which did not take up 18F-FDG on positron emission tomography. Exploratory thoracotomy revealed a pedunculated neoplasm which was removed by standard lobectomy. Histopathological diagnosis indicated the presence of smooth muscle spindle cells but absence of mitotic activity, nuclear atypia or necrosis, leading to a diagnosis of pulmonary parenchymal leiomyoma. Four months after surgery, the patient experienced a noticeable reduction in the finger clubbing. Hypertrophic osteoarthropathy may be the presenting characteristic of benign masses such as pulmonary leiomyoma.