Unusual bony lesions of histiocytosis X in a patient previously treated for Hodgkin's disease.

We present an unusual case of multifocal Histiocytosis X in a 78-year-old man treated for Hodgkin's Disease 33 and 24 years previously. The Hodgkin's Disease at first involved cervical nodes and 9 years later axillary and inguinal nodes and was treated by radiotherapy. Chronic destructive lesions developed in the femora and pelvis and bone biopsies showed a curious mixture of fibroblastic tissue and foamy macrophages. These lesions eventually resulted in pathological fractures of the femoral necks, and bilateral hip replacements were required seven years after initial detection of the bony lesions. There was a focal infiltrate of S-100 protein positive histiocytic cells containing Birbeck granules in the femoral heads. There was radioisotopic and radiological evidence of other skeletal lesions. The association between Histiocytosis X and Hodgkin's Disease is recognised but rare and its significance is discussed.