[Refractory hypercalcemia in patient with lung cancer]

Hypercalcemia is a common complication of malignancy which recognition is usually delayed. Severe hypercalcemia can lead to death. Mechanisms of hypercalcemia of malignancy include excessive production of parathyroid hormone related protein (PTHrP), local osteolysis, absorptive hypercalcemia due to overproduction of calcitriol and ectopic parathormone (PTH) production. Volume expansion with normal saline solution, loop diuretics and intravenous bisphosphonates are mainstays of therapy for hypercalcemia. As an adjunctive therapy calcitonin and corticosteroids are used. In refractory cases gallium nitrate and denosumab can be an option. In patients with severe acute kidney disease hemodialysis with a low-calcium bath is an alternative treatment. In this paper we present a case of severe, refractory hypercalcemia in 53-years old patient with squamous cell carcinoma of the lung and multiple metastases to bones. Despite intensive treatment, that included also intravenous bisphosphonates, patient relapsed on therapy and didn't respond to subsequent doses. Patient received subcutaneous denosumab with good hypocalcemic effect. In this paper we present pathogenesis and treatment of hypercalcemia, including advantages and limitations of denosumab.