Long-term administration of calcitonin for hypercalcemia secondary to recurrent parathyroid carcinoma

Abstract

A patient with hypercalcemia secondary to recurrent parathyroid carcinoma was treated for 44 days with intramuscular and intravenous injections of porcine calcitonin and on day 45 with synthetic salmon calcitonin. There was no sustained control of serum calcium during this period, but the concentration decreased transiently with intravenous administration of both types of calcitonin. No serial measurements of serum calcium were made following intramuscular administration; therefore, it is not known whether this route of administration produced similar results. Dosage and route of administration of calcitonin warrant further investigation in controlling hypercalcemia secondary to parathyroid hormone excess. No difference in the degree or duration of decreasing the serum calcium concentration was noted following comparable doses of intravenous infusions of porcine calcitonin and of synthetic salmon calcitonin on separate days. Parathyroid hormone levels measured during the infusion of synthetic salmon calcitonin remained elevated at essentially the same level before and after the infusion. A steady decline in urinary phosphorous excretion during the treatment period could not be explained with certainty.