A comparison between flow cytometric assessment of S-phase fraction and Nottingham histologic grade as prognostic instruments in breast cancer

Flow cytometric DNA analysis with assessment of S-phase fraction and DNA pl oidy was compared to Nottingham histologic grade. The study population cons isted of 654 patients who presented between 1987 and 1996 with primary oper able breast cancer and whose tumours had been analysed for S-phase fraction and DNA ploidy at the time of surgery. Grade, tumour size, node status, st eroid receptor status, age, S-phase fraction and DNA ploidy were analysed u nivariately and multi-variately in a Cox proportional hazard analysis. In t he univariate analyses all parameters were statistically significantly asso ciated with breast cancer mortality during the follow-up period of 2-11 yea rs. The most powerful predictor of death from breast cancer in the multiple regression analysis was grade. Patients with grade 1 tumours have excellen t prognosis. We conclude that tumour grade is a strong prognostic indicator applicable to all breast cancer patients, regardless of size and nodal sta tus, and advocate its general use.