Diffuse osteosclerosis as a presentation of recurrent breast cancer: role of endothelin 1

Abstract

Summary: We report a 46-yr-old woman with a history of breast cancer who presented with diffuse myalgias, bone pain, and osteosclerosis. She was found to have recurrent breast cancer producing endothelin-1. Introduction: Acquired osteosclerosis can be caused by various disorders. Endothelin -1 is believed to contribute to osteosclerosis caused by breast cancer. Methods: Although the bone marrow biopsy did not reveal breast cancer, she developed skin lesions consistent with metastatic breast cancer. She ultimately died from progressive disease. At autopsy immunohistochemistry for endothelin-1 was performed on a section from the L5 vertebral body. Results: The section from the L5 vertebral body showed small foci of cells consistent with metastatic carcinoma and a prominent sclerotic response. Immunohistochemistry for endothelin-1 was strongly positive. Conclusions: Recurrent breast cancer may present with diffuse osteosclerosis. Endothelin-1 may be a paracrine factor responsible for increased bone formation and osteosclerosis.