Receptor status variation in primary breast cancer and subsequent accessible relapse

To better understand the prognostic relevance of change in steroid receptor status, during the clinical course of breast cancer, we analysed the variation of estrogen and progesterone receptor (ER, PgR) status in a series of 532 primary tumors and metachronous accessible recurrences in individual patients. A more consistent variation was observed in patients with a receptor-positive primary (ER(+) or PgR(+)) than in those with a receptor-negative tumor (ER(-) or PgR(-)). Forty-four percent of PgR(+) and 24% of ER(+) tumors became negative, whereas only 20% of ER(-) or PgR(-) became positive. The changes were independent of tumor stage and menopausal status. However, steroid receptor variation appeared to be related to the interval between the primary tumor and relapse. In fact, the changes from ER(+) to ER(-) were more frequent in patients with a disease-free survival of less than 1 year, whereas changes from ER(-) to ER(+) occurred more often in patients with a disease-free survival of more than 3 years. Moreover, we observed a decrease in the number of ER(+) tumors following hormone treatment and a decrease in ER(-) tumors following chemotherapy. However, such variations did not reach statistical significance. Irrespective of the type of adjuvant therapy, the presence of at least one receptor (in particular, PgR) in the metachronous lesion was correlated with a long median time to relapse and to death. Our results confirmed the predictive relevance of receptor status of the primary lesion on relapse and survival and suggest the predictive relevance of receptor status of the metachronous lesion on post-relapse survival.