Steroid receptors and prognosis in operable (stage I and II) breast cancer.

Four hundred and forty-seven women with operable (TNM stage I or II) breast cancer in whom oestrogen receptors (ER), progesterone receptors (PgR) or both receptors had been assayed were studied. Receptor status was independent of axillary nodal status, but infiltrating duct carcinomas that were ER-, PgR- or ER-PgR- were more likely to be anaplastic (P less than 0.001). Four hundred patients with follow-up and uniform treatment were analysed for post-operative disease-free interval (DFI) and survival. No significant difference in DFI existed between patients with ER+ and ER- tumours or PgR+ and PgR- tumours, although there was a trend for longer DFI for ER+ and PgR+. DFI was longer in patients with better-differentiated (grade 1 and 2) tumours than with anaplastic (grade 3) tumours. In patients with ER+ tumours, those with grade 1 and 2 tumours had a longer DFI than those with grade 3 tumours (P less than 0.005). Survival was significantly longer in patients with ER+ tumours compared to those with ER- tumours (P less than 0.001), but there was no such association between tumour PgR and survival. Survival of patients with ER+PgR+ tumours was significantly longer than those with ER-PgR- tumours (P less than 0.025) and, in patients with no evidence of axillary nodal involvement, significantly longer than those with ER+PgR- tumours. Survival in patients with nodal involvement was influenced by histological grade, being longer in those with grade 1 or 2 tumours compared to those with grade 3 tumours. For ER+ tumours, survival was longer in patients with grade 1 or 2 than with grade 3 tumours. These results suggest that steroid receptors significantly affect survival but not DFI. This effect is most closely related to ER content, with relatively little additional information accruing from analysis of PgR. Histological grade influences both DFI and survival, and analysis of both grade and ER content may give a more accurate indication of prognosis in operable breast cancer.