Effects of the acute subcutaneous administration of synthetic salmon calcitonin in tumoral calcinosis

Abstract

We examined the effects of the acute administration of salmon calcitonin on phosphate metabolism in tumoral calcinosis. On two different days, 200 MRC U of the synthetic hormone were administered sc to a 38-year-old patient, either as twice daily 100 MRC U injections, or as a continuous sc infusion via a portable pump. Both ways of calcitonin administration elicited a phosphaturic effect and a lowering of serum phosphate level comparable with that observed after an iv infusion of calcitonin. 1,25 dihydroxyvitamin D level, which was in the normal range during a control study, increased after calcitonin administration. In our patient, long term therapy with diet, a phosphate-binding agent and calcitonin prevented the occurrence of new ectopic calcifications. Owing to its phosphaturic activity, synthetic salmon calcitonin may be a useful adjunct to diet and aluminium-containing antacids in long-term management of tumoral calcinosis.

Tumoral calcinosis-like lesion of the proximal linea aspera

“…Hyperphosphatemia has been found in some individuals, but serum calcium and parathyroid hormone levels are reported normal [3,21,22,24,26,32,34,35,38,45]. An apparent inherited disorder of phosphate and vitamin D metabolism has also been described [8,19,28,34,37,38,48]. Trauma has been implicated as a cause in selected patients [5,10,15,30,36,39,42,44].…”

Hyperphosphatemic familial tumoral calcinosis (FGF23, GALNT3 and αKlotho)

“…Calcitonin was demonstrated to increase fractional excretion of phosphate and decrease serum phosphate in hFTC patients [83–85]. However the published response of TC lesions to this treatment is limited.…”

“…However the published response of TC lesions to this treatment is limited. In one patient the TC lesion did not progress during treatment [83], but in two other patients, there was an apparent increase in size of the TC lesions [85]. …”

“…These effects on FGF23 and 1,25D would be the opposite of the desired goals for biochemical management of TC. However, although short term calcitonin did increase serum 1,25D in one TC patient [83], the authors noted lack of new lesions during long term treatment.…”

Differential response of idiopathic sporadic tumoral calcinosis to bisphosphonates

“…However, the response is variable and this approach does not address the normophosphatemic variant of tumoral calcinosis. The approach to medical management of hyperphosphatemia is twofold-limiting absorption (phosphate-restricted diet,[4] phosphate binders-lanthanum, sevelamer[5]) and increasing renal clearance (acetazolamide,[6] calcitonin[7]). Dialysis with low phosphate containing dialysate and parathyroidectomy for severe secondary hyperparathyroidism has also been tried.…”