[Immunohistological evaluation of parathyroid hormone-related protein in breast cancer with and without calcification on mammography].

: PTHrP is the main factor of humoral hypercalcemia of malignancy. PTHrP produces the same effect on renal and osteoblast membrane in vitro and on calcium and inorganic phosphate fluxes in vivo as human PTH. Physiologically, PTHrP is produced by rat mammary tissue during lactation. It is suggested that PTHrP correlates to the metabolism of calcium in the mammary gland. Using anti-PHTrP (1-34) monoclonal antibody 4B3, we investigated the correlation of PTHrP and calcification in breast cancer. All the breast cancers with calcification on mammography showed positive immunostaining. Most cases without calcification, on the other hand, showed negative. Positive PTHrP staining was not related to the any clinical parameter. It is suspected that PTHrP is also one of the main factors of calcification in breast cancer.