Abstract P2-10-37: Long-term prognosis of early breast cancer in a population-based cohort with a known BRCA1/2 mutation status.

Abstract

Abstract Background: The impact of germline BRCA1/2 mutations on breast cancer prognosis and treatment is currently not clear. We investigate how different factors, including BRCA1/2 mutation status, correlate with long-term outcome in early breast cancer in a population-based cohort. Methods: As previously reported, all women in the Southern Health Care Region in Sweden with breast cancer diagnosed before age 41 years between 1990 and 1995 (n = 262) were contacted in 1996 and offered mutation analysis of the BRCA1 and BRCA2 genes. Mutation analysis was performed on 234 of them, the others were excluded from further studies. 23 pathogenic mutations were found; 18 in BRCA1 and 5 in BRCA2. We will now present data on tumor and patient characteristics, treatment and long-term follow-up for the patients from this population-based cohort. Three patients have declined further study follow-up and were therefore excluded. Six patients had metastatic breast cancer at the time diagnosis (one of them a BRCA2 mutation carrier) and are also excluded, leaving 225 in the present analysis. Results: Among the 225 cases estrogen receptor (ER) status is known for 191 (49% ER+, 51% ER−); histologic grade for 169 (24% grade I; 33% grade II; 43% grade III); stage for 225 (36% stage I, 44% stage II, 20% stage III); type of surgery, adjuvant systemic treatment and postoperative radiotherapy for 225. In the cohort, 46% received adjuvant or neoadjuvant chemotherapy, whereas 15% were given adjuvant endocrine therapy. There is complete follow-up > 10 years for 205 and present vital status for 224. Of the 225 women, 128 (57%) have had a local, regional or distant recurrence of breast cancer (contralateral breast cancer not included) at the date of last follow-up. One hundred and six patients (47%) have died, 98 of whom from breast cancer and 2 from presumably radiation-induced malignancies caused by postoperative radiotherapy. Thirteen of the 22 BRCA1/2 mutation carriers (59 %) have died, all from breast cancer. Of the 9 mutation carriers that are alive today, 3 have had an in-breast tumor recurrence and 3 have had a contralateral breast cancer; the 3 women that have had neither have all performed bilateral prophylactic mastectomy as well as prophylactic salpingo-ooforectomy. Data on how the long-term prognosis of early breast cancer is correlated to BRCA1/2 mutation status, adjuvant treatment, stage at diagnosis, histologic grade and ER status of the tumor will be presented. Conclusion: Women with early breast cancer in this cohort from the early 90ies had a poor long-term prognosis. The prognosis for women diagnosed with early breast cancer today is likely to be better, thanks to more modern chemotherapy regimens, endocrine and targeted treatments. The prognostic significance of BRCA1/2 mutation status will be further analyzed. Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P2-10-37.