A Giant Humeral Parosteal Lipoma

Parosteal lipomas are exceedingly rare and can pose diagnostic challenges due to their unusual imaging characteristics. Here, we report the case of a 70-year-old man who presented with a large painless shoulder mass that caused functional limitation. Imaging revealed a predominantly fatty lesion with an osseous excrescence and irregular cortical changes. Biopsy confirmed a parosteal lipoma, a rare benign fatty tumor arising directly on the bone cortex. Despite the atypical imaging features, which can mimic more aggressive tumors, surgical excision was performed due to the size and functional impact. After three years, the patient showed no recurrence and improved shoulder range of motion.