Abstract

Osteochondromas in hereditary multiple exostosis have increased risk of malignant transformation as compared with solitary osteochondromas. We present a case of a 54-year-old man who presented to us with complaints of swollen mass of the left shoulder with an ulcerative lesion. Radiograph showed a sessile growth from the proximal humerus and scapula. MRI revealed a sessile osteochondroma measuring about 11×10.1×8.0 cm. The malignant nature of the disease was anticipated due to increased cap thickness and non-healing ulcer, however, biopsy showed a benign lesion without any sarcomatous change. The patient was successfully treated with extra-periosteal excision and was recurrence-free at 24 months follow-up. This case illustrates an extra-articular giant osteochondroma of the proximal humerus, with possible signs of a malignant lesion but diagnosed benign on biopsy. We conclude that a biopsy should always preclude definitive management as this can change the overall mortality and morbidity of the patient.