Summary A prognostic index, previously derived in a group of 387 patients with primary breast cancer, has been recalculated for the same patients with over 5 years further follow-up and shown to be unchanged. The prognostic index has also been applied prospectively to a further group of 320 patients and shown to be similarly effective in identifying patients with either a very good or a very poor prognosis. It has been verified that the index applies to patients with primary breast cancer. Patients have now been divided into 5 prognostic groups, predicting 11% of patients with an almost normal survival and a further 10% with a very poor prognosis. The index is used to stratify patients to study the effects of treatment regimes within groups of similar patients.It would be of considerable value in the management of breast cancer patients to be able to predict more accurately the clinical course of the disease at the time of initial treatment. In studies of breast cancer many factors may appear to indicate prognosis if studied in isolation or in small groups. To obtain a true indication of the prognostic importance of these factors it is necessary to employ a form of multivariate analysis such as that described by Cox (1972) which can make use of all the data from a group of patients having a wide range of survival times.The where size is in cm, stages A, B and C (see below) are coded 1-3 and grade is also coded 1-3.The index was computed for each patient, who was then assigned to one of three prognostic groups: Good (1<3.4), Moderate (3.4 5.4).Lifetable analysis of the patients in the Good prognostic group showed a survival of 88% at 5 years against 21 % in the Poor prognostic group. Since the method of obtaining the index relied on the best fit to retrospective data it is essential to perfect the index prospectively. This paper applies the prognostic index prospectively to a second group of patients with primary breast cancer who have presented since since our first report.The power of the prognostic factors might alter with time, e.g., factors predicting survival at 10 years might be different from those predicting 5 year survival. The analysis has been re-applied to the original group of patients, now with longer follow-up. Patients and methodsThe patients in the two groups were treated under the care of a single surgeon (RWB)

Summary ER content of primary tumour tissue has been examined in 704 patients presenting with operable breast cancer. The median follow-up is now 84 months and no patient has received adjuvant therapy of any kind.ER status is related to histological grade, menopausal status, initial site of metastases and subsequent response to endocrine therapy.A significant advantage in terms of survival is found in ER positive patients which is confined to those lymph node positive at mastectomy. DFI is also significantly related to ER status in lymph node positive patients.Survival after the symptomatic presentation of metastases and the institution of endocrine therapy is prolonged in patents with ER positive tumours. The overall response rate to endocrine therapy in assessable patients with ER positive tumours is 32%. By combining the ER status and histological grade of tumour tissue, a group of patients comprising 28% of those assessable to endocrine therapy can be identified (ER positive, grade I and 11) with a response rate of 46%.

The DNA content of paraffin embedded primary tumour tissue has been measured by flow cytometry in 354 patients with operable breast cancer. Tumour ploidy significantly correlated with tumour size, histological grade, and with menopausal status. No significant correlation with oestrogen receptor status or lymph node involvement was found. Patients with diploid cancers had a significantly improved short term survival and disease-free interval (DFI) compared with patients having aneuploid tumours. However, no difference in survival or DFI was shown after longer term follow-up (median 84 months). Multivariate analysis showed no independently significant prognostic value for tumour ploidy. No patient in this study received adjuvant therapy.

Summary Cellular DNA content of primary tumours from 280 patients with operable breast cancer was determined by flow cytometry using nuclei from paraffin sections stained with DAPI, and 199 of these patients were followed for 8-13 years after surgery. Tumours from 67 patients have also been analyzed for their DNA content using single cell suspensions from fresh tumour tissue stained with mithramycin and ethidium bromide, and the results compared with those obtained from paraffin blocks of the same tumours.Overall