Proliferative index, cytosol estrogen receptor and axillary node status as prognostic predictors in human mammary carcinoma.

The predictive value of tumor cell estrogen receptor (ER) content, DNA ploidy, proliferative index (PI) and lymph node involvement was examined in 210 women operated on for primary breast cancer in 1979. At a minimum follow-up of 60 months the highest relapse free survival was observed in patients whose tumours had ER greater than 0.30 fmole/micrograms DNA (ER rich) and PI less than 5% (PI low). Subclassification of tumors in euploid and aneuploid groups gave no prognostic information. When examined by axillary node status (no nodal involvement - involved nodes) both ER and PI contributed prognostic information. Multivariate analysis using Cox proportional hazards model showed that nodal involvement was the strongest predictor of recurrence (p = 0.0007). However, ER and PI contributed significant independent prognostic information (p = 0.048 and p = 0.038), respectively.