PROGNOSTIC-SIGNIFICANCE OF DNA-PLOIDY IN A SERIES OF 690 PRIMARY BREAST-CANCER PATIENTS

Flow cytometric DNA‐ploidy measurements were performed on paraffin‐embedded and fresh tumor specimens from 690 patients with Stage I‐III breast cancer. The conventional classification of DNA‐ploidy (diploid versus aneuploid) was compared with a division of tumor ploidy into 5 classes based on DNA index (DI) range. The DI‐classification showed a better correlation with tumor size and TNM stage than the conventional classification. Aneuploidy was associated with an impaired survival and distant relapse‐free survival (p =0.02) but the DI‐classification improved the discrimination between different prognostic groups of patients. In general, this indicated a more aggressive phenotype for tumors evolved via polyploidization. Hyper‐tetraploidy (DI >2.10) indicated a very poor prognosis in pre‐menopausal patients. No prognostic effect of aneuploidy and DI‐class was found in node‐negative and TI patients. Cox multivariate regression analysis showed that aneuploidy was an additional prognostic factor to nodal status (1 < N < 3, N > 3 vs. N =0) and tumor size (T2‐4 vs. T1) for overall and distant relapse‐free survival. Subdivision according to DI‐class did not improve the prognostic power of DNA‐ploidy due to stronger correlations with established prognostic factors. Copyright © 1990 Wiley‐Liss, Inc., A Wiley Company