Eosinophilic granuloma of bilateral humerus with unusual diagnostic process.

A 15-year-old boy presented with a right shoulder pain and the inability to use his right upper limb after carrying a heavy object. Physical examination and local imaging revealed a benign tumor or tumor-like lesion in the upper ends of both humeri and a pathologic fracture in the right humerus. An initial biopsy was reported as fibroblastic osteosarcoma. But the CT-guided biopsy was diagnosed as eosinophilic granuloma (EG). Bone curretage and grafting confirmed diagnosis of EG. This case illustrates the importance of combining a clinical impression with imaging and pathology in bone and soft tissue tumors.