Severe hypophosphatemic osteomalacia in hormone-refractory prostate cancer metastatic to the skeleton: natural history and pitfalls in management

We report the case of a severe symptomatic hypophosphatemic osteomalacia in a 66-year-old patient with hormone-refractory prostate cancer metastatic to the skeleton. A follow-up of 2 years from diagnosis to development of hormone refractoriness and death allowed us to study the natural history of this uncommon disturbance of mineral homeostasis in this common malignancy. Relevant to the difficult management of the late stages of prostate cancer is the failure of hypophosphatemia to respond to conventional therapeutic approaches and the favorable outcome of antitumor therapy suggesting that this group of patients, although having a poor prognosis, could still benefit from aggressive second line therapy. In this malignancy in which metastases have a predilection for bone, failure to recognize osteomalacia can only result in significantly increasing the burden of skeletal complications.