Iliac osteosarcoma in a patient with SAPHO syndrome

Extrathoracic sclerotic bone involvement of SAPHO syndrome are sometimes very difficult to differentiate from a bone infection or bone tumor. The authors report the case of a 46-year-old patient with a history of palmo-plantar pustulosis, recurrent suppurative hidradenitis, and bilateral sternocostal arthropathy who was evaluated for a sclerotic lesion in an iliac wing. The clinical course, computed tomography findings, and histologic features of a surgical biopsy specimen established the diagnosis of osteoblastic osteosarcoma with SAPHO syndrome.