PTHLH and Familial prostate cancer: Hypercalcemia is reportedly rare in prostate cancer.[24] Certain reasons may explain the low rate of symptomatic hypercalcemia in prostate cancer, including osteoblastic activation, which hampers massive calcium release into the bloodstream from the metastatic sites and induces a ‘calcium sink’ effect[15] and the possible role of PSA in inactivating parathyroid hormone-related protein produced by cancer cells.[25] In contrast, hypocalcemia is a metabolic disturbance more common in advanced prostate cancer due to the bone hunger syndrome.