Survival of breast cancer patients in BRCA1, BRCA2, and non-BRCA1/2 breastcancer families: A relative survival analysis from Finland

Reports on the prognosis of familial breast cancer patients have been contr adictory, True differences in survival, if they exist, would have important implications for genetic counselling and in treatment of hereditary breast cancer, We assessed the survival rates of 359 familial breast cancer patie nts (32 patients from BRCA1-positive families, 43 patients from BRCA2-posit ive families and 284 patients from BRCA1/2-negative breast cancer families) and compared them with those of all other breast cancer patients diagnosed in Finland from 1953 to 1995 (n = 59,517), Cumulative relative survival Fa tes (RSR) were calculated by dividing the observed survival rates by the ex pected ones. The expected survival rates were derived from the sex, age and calendar year specific life-tables of the general population in Finland, R egression model was used to calculate relative excess risk of death (RR) an d to adjust for confounding factors. The overall 5-year RSR of the patients in the BRCA1 families, BRCA2 families, non-BRCA1/2 families and among spor adic cases was 67%, 77%, 86% and 78%, respectively. However, we found no si gnificant differences in the RR adjusted for age, stage and year of diagnos is between the different familiar patient groups or the general breast canc er population. In the BRCA1 families the RR tended to be higher [RR 1.30, 9 5% confidence interval (CI) 0.63-2.70] and in the BRCA2 families lower (RR 0.78, 95% Cl 0.39-1.57) than among the general breast cancer patient popula tion. The RR among patients in the non-BRCA1/2 families did not differ from that of the general patient population, (C) 2001 Wiley-Liss, Inc.