In another study, [177Lu]Lu-DOTA-TATE therapy in previously normocalcemic patients with NETs (n=47) resulted in significant reductions in serum calcium levels and a significant increase in serum parathyroid hormone (PTH) levels manifesting as secondary hyperparathyroidism when followed up to 6 months after therapy, and 11% of the patients required calcium supplementation (26). Here, PTH is linked to secondary hyperparathyroidism.