Survival and prognostic factors in BRCA1-associated breast cancer
Annals of Oncology , Volume 17 - Issue 3 p. 391- 400
Background: Studies comparing survival in BRCA1-associated and sporadic breast cancer (BC) report inconsistent results and frequently concern small sample sizes. Further, the prognostic impact of the classical tumour and treatment factors is unclear in BRCA1-associated BC. Patients and methods: We selected 223 BC patients diagnosed between 1980 and 2001 within families with a deleterious germline BRCA1-mutation ascertained at the Rotterdam Family Cancer Clinic. To correct for ascertainment bias, the group of index patients undergoing DNA testing more than 2 years after BC diagnosis (n = 53) was separated from the other BRCA1-patients (n = 170). All BRCA1-associated patients were matched in a 1:2 ratio for age and year of diagnosis to sporadic BC patients. We compared the occurrence of ipsi- and contralateral BC (CBC) as well as distant disease-free (DDFS), BC-specific (BCSS) and overall survival (OS). By multivariate modelling, the prognostic impact of tumour and treatment factors was investigated separately in BRCA1-associated and sporadic breast cancers. Results: For the total group of 669 cases, the median follow-up was 5.1 years, the median age at diagnosis 39 years. We confirmed the existence of the typical BRCA1-associated tumour type and the high CBC incidence. No significant differences between BRCA1-associated and sporadic tumours were found with respect to ipsilateral BC recurrence (HRmult 0.7; P = 0.24), DDFS (HRmult 1.2; P = 0.37) or BC-specific survival (HRmult 1.3; P = 0.23). A trend towards a worse survival was found for BRCA1-associated ductal BC (HRmult 1.5, P = 0.07). Prognostic factors for BRCA1-associated BC were age at diagnosis, tumour size and morphology, and nodal status. Further, survival was non-significantly improved by systemic treatment and a bilateral salpingo-oophorectomy. No effect on survival of a contralateral prophylactic mastectomy was seen. Conclusions: BRCA1-associated BC is characterised by specific tumour characteristics, a high incidence of CBC and a trend towards a worse survival for the ductal tumour type. Our observation that tumour size and nodal status are also prognostic factors for BRCA1-associated BC implies that the strategy to use these factors as a proxy for ultimate mortality, for instance in BC screening programmes or the consideration of (contralateral) preventive mastectomy, appears to be valid in this specific group of patients.
|BRCA1, Breast cancer, Hereditary, Histopathology, Prognostic factors, Survival|
|Annals of Oncology|
|Organisation||Erasmus MC: University Medical Center Rotterdam|
Brekelmans, C.T, Seynaeve, C.M, Menke-Pluymers, M.B.E, Brüggenwirth, H.T, Tilanus-Linthorst, M.M.A, Bartels, C.C.M, … Klijn, J.G.M. (2006). Survival and prognostic factors in BRCA1-associated breast cancer. Annals of Oncology, 17(3), 391–400. doi:10.1093/annonc/mdj095