Estrogen and progesterone receptors in breast cancer patients. Epidemiologic characteristics and survival differences.

Risk factors commonly associated with breast cancer were studied in relation to: (1) tumor estrogen receptor (ER) or progesterone receptor (PR) status and (2) the presence of tumor hormone receptors in relation to subsequent survival. For 171 Israeli women diagnosed with breast cancer in 1976 to 1979, tumor hormone receptor status (positive if greater than 20 fmol receptors/mg protein; negative if less than or equal to 20 fmol/mg) and survival as of April 1984 were ascertained. There were 77 ER- versus 94 ER+ and (for 134 PR analyses) 69 PR- versus 65 PR+. Although ER status and PR status were found to be highly positively related, the epidemiologic features of women with an ER+ tumor were different from those with a PR+ tumor. Age tended to be associated positively with both ER+ and PR+. Being postmenopausal, older at menopause or at first birth, nulliparous, having more years of schooling, and a higher body mass index for older women or a lower body mass index for younger women were correlated positively with ER and negatively with PR. Among women with Stage III or IV tumors at diagnosis significant differences existed: restricted mean survival for follow-up time was 47.2 months for ER-, 73.8 months for ER+, 45.8 months for PR-, and 61.9 months for PR+. The combined hormone effects on survival at Stages III to IV showed a similar trend: restricted mean survival of 38.4 months for ER-PR-, intermediate survival with one positive hormone receptor status, and 74.6 months for ER+PR+.