A clinical case of phosphopenic osteomalacia due to paraneoplastic secretion of metastatic prostate cance

Abstract

Phosphaturic mesenchymal tumor can cause osteomalacia due to excessive secretion of fibroblast growth factor 23 (FGF23), which disrupts the metabolism of phosphate and vitamin D. These tumors are predominantly benign, but less than 5% of them are malignant forms. This article presents the first clinical case in the Russian Federation of a 69-year-old patient with severe hypophosphatemia due to metastatic prostate cancer. Increased secretion of FGF23 are described in the androgen-resistent prostate cancer, which led to pronounced disorders of mineral metabolism, accompanied by a clinical symptom of weakness, pain in the bones, immobilization of the patient. The condition was regarded as worsening against the background of the progression of the disease. However, symptomatic therapy aimed at increasing the level of phosphate significantly improved the patient’s general condition. The medical community should be aware of the possibility of developing hypophosphatemia in patients with weakness and bone pain, which are not always associated with the progression of metastatic prostate cancer.