149 The influence of young age on disease free survival in stage I breast cancer

ONCOPOOL pooled data from 12 European Breast Units, from 16,944 cases of operable ( 5 cm) invasive breast cancers aged 70, diagnosed consecutively on each unit in 1990−99 inclusive, with first line operative treatment. It is of interest to compare the data with another large data set; SEER has long been quoted as the standard for comparisons of tumour factors and outcomes. SEER is USA based. The data examined is from the 2 large data sets on women with primary breast cancers, with only cases obeying the same inclusion factors as for ONCOPOOL used for the SEER data. Comparisons will be of: Numbers entered, Age at entry, Tumour size, lymph node status (sampling or clearance required), size .v. LN status, grade (and method used), ER and PgR status, grade .v. size, grade .v. ER status (pos, neg), formulae for relation of LN negativity and size to grade, Overall (OS) and Breast Cancer Specific Survival (BCS) for all cases at intervals to 180 months. The data from each set will be applied to indices combining prognostic factors to estimate survivals (Nottingham Prognostic Index and FIN-PROG Index) and polynomial curves for each data set relating survival to index levels produced. Combined data (extra data will be added from FINN PROG and Uppsala). Using the indices the combined data will be entered to estimate the effects of adjuvant therapies (eg) Cox analysis will be applied entering the prognostic index values and survival for treatment with hormone; also polynomial curves will be produced of survival against index value to allow comparisons of treatments (eg) no adjuvant therapy against endocrine only in ER+ cases. The percentage risk reductions obtained will be compared with those shown by the EBCTCG Meta Analysis. Work at present shows a differential proportional effect in relation to prognosis, which the Meta Analysis is unable to demonstrate. Effects in other situations can similarly be examined: effects of screening; radiotherapy after Breast Conserving Surgery by Van Nuys prognostic index.