Specific high affinity receptors for 1,25-dihydroxyvitamin D3 are present in several human breast cancer cell lines, and this hormone can regulate the replication of these cells. These receptors are also present in primary breast carcinomas. The present study has resulted from the follow-up for up to 68 mo of 263 women, who had had 1,25-dihydroxyvitamin D receptor (1,25-DR) levels measured in their primary tumors. Survival data on 191 women were correlated with the levels of 1,25-DR and other steroid hormone receptors, menopausal status, and age by life table analysis. Survival was not affected by 1,25-DR level in either absolute terms or relative levels. However, the late development of lymph node metastases in eight of 47 individuals was correlated with the 1,25-DR level (P = 0.05). There was no correlation between 1,25-DR or other hormone receptor levels and the development of hypercalcemia or bone metastases in the small number of individuals so affected. As we had observed previously, there was no correlation between the level of 1,25-DR and that of the other steroid hormones. These data show that the presence of 1,25-DR in primary breast cancers is independent of other prognostic indicators and, inasmuch as it correlated with late lymph node metastasis, may be an adverse prognostic indicator.
These studies were supported by grants from the National Health and Medical Research Council, the Anti-Cancer Council of Victoria, Hoffmann-La Roche Inc., and the New South Wales State Cancer Council.