Is Endogenous Prolactin, Not Endocrine Prolactin, Responsible for Hyperparathyroidism in Breast Cancer Patients?

Breast cancer is the most common site-dependentcancer among females and the main cause of deathdue to malignancy in females aged ۴۰-۴۴ years. Thisillness is responsible for ۳۳% of all gynecologicalmalignancies and ۲۰% of all females' mortality.According to the reported statistics in the USA, theprobability of developing breast cancer is one inevery ۸ women.۱Hypercalcemia in patients with breast cancer isgenerally considered a result of osteolytic metastasisor circulating tumor derived products. In suchsituations, severely depressed plasma parathormone(PTH) is expected. Hypercalcemia in malign- ۲,۳ancies is multifactorial, and results from acombination of increased bone resorption associatedwith decreased renal excretion of the increasedextra-cellular fluid calcium. One of the most ۴frequent etiologies of hypercalcemia is hyperparathyroidismwhich is usually neglected in breastcancer patients, while recent studies have shownincreased incidence of primary hyperparathyroidismin breast cancer patients regardless ofclinical staging or anti-tumor therapy.