[Prognostic significance of progesterone receptor in breast cancer]

Estrogen and progesterone receptors (ER and PR) were detected in 400 women with primary breast cancer from 1979 to 1986. Cytosols showing saturable binding of 10 fmol/mg protein or more were taken as positive for ER and PR. The positive rate was 55.5% and 42.8%, respectively in this series. PR negative patients had higher risk of early recurrence than PR positive patients according to the highly significant difference between the two disease-free survival curves (P less than 0.01). The relative risk of recurrence in the PR negative group was 3.2 times higher than PR positive group (P less than 0.01). Simple ER positive or ER negative did not provide any relevant information for predicting the disease-free survival in this present series. Thirty months after mastectomy, 32.2% of the patients with PR negative tumors had recurrent disease as compared with the PR positive group (10.2%) (p less than 0.01). The recurrent rate was negatively correlated with tumor PR concentration. The prognostic value of PR status with respect to clinical stage, menopausal status and axillary node involvement is discussed. It is concluded that the PR content of breast cancer is an important predictor of prognosis and will help us to formulate treatment plan for the patients.