Purpose: Expression of PTHrP is immunohistologically found in mammary tissues of all the normal cell, hyperplasia and malignant cell. In patients of breast cancer, positive ratio of PTHrP is reportedly 60-69%. Higher positive ratios of PTHrP are found in breast cancer showing bone metastasis than those without bone metastasis. And, breast cancer patients with PTHrP positive show poor prognosis suggesting a relationship to histological grade. Regarding PTHrP receptor, there is few report on its physiological role and relationship to other prognostic factors. The aim of this study was to determine the correlation between PTHrP receptor and various prognostic parameters of breast cancer patients with no axillary node metastasis.
Material and methods: We employed 26 breast cancer patients, who showed negative axillary node metastasis and did not receive postoperative therapy. We examined relationship between PTHrP receptor and various prognostic factors such as hormone receptors, MIB-1 index, proliferation of cell nuclear antigen (PCNA), DNA ploidy, S-phase fraction, age, tumor diameter, c-erbB-2, and Cathepsin D.
Results: No relationship between expression of PTHrP receptor and the cancer recurrence. PTHrP receptor correlated MIB-1 index alone (p < 0.044).
Conclusions: This findings suggest PTHrP receptor is related to the tumor proliferation of breast cancer.