RESUMO
IMPORTANCE: Women who carry a germline mutation in either the BRCA1 or BRCA2 gene face a lifetime risk of breast cancer of up to 70%, and once they receive a diagnosis of breast cancer, they face high risks of both second primary breast and ovarian cancers. Preventive bilateral salpingo-oophorectomy is recommended to women with a BRCA mutation at age 35 years or thereafter to prevent breast and ovarian cancer, but it is unclear whether oophorectomy has an impact on survival in women with BRCA-associated breast cancer. OBJECTIVE: To estimate the impact of oophorectomy on survival in women with breast cancer with a BRCA1 or BRCA2 mutation. DESIGN, SETTING, AND PARTICIPANTS: Retrospective analysis of patients selected by pedigree review of families who received counseling at 1 of 12 participating clinical genetics centers. Patients were 676 women with stage I or II breast cancer and a BRCA1 or BRCA2 mutation who were observed for up to 20 years after receiving a diagnosis between 1975 and 2008. Survival experience was compared for women who did and who did not undergo oophorectomy. MAIN OUTCOMES AND MEASURES: In all analyses, the primary end point was death due to breast cancer. RESULTS: Of the 676 women, 345 underwent oophorectomy after the diagnosis of breast cancer and 331 retained both ovaries. The 20-year survival for the entire patient cohort was 77.4%. The adjusted hazard ratio for death attributed to breast cancer in women who underwent oophorectomy was 0.38 (95% CI, 0.19-0.77; P = .007) for BRCA1 carriers and 0.57 (95% CI, 0.23-1.43; P = .23) for BRCA2 carriers. The hazard ratio for breast cancer-specific mortality was 0.76 (95% CI, 0.32-1.78; P = .53) for women with estrogen receptor-positive breast cancer and 0.07 (95% CI, 0.01-0.51; P = .009) for women with estrogen receptor-negative breast cancer. CONCLUSIONS AND RELEVANCE: Oophorectomy is associated with a decrease in mortality in women with breast cancer and a BRCA1 mutation. Women with estrogen receptor-negative breast cancer and a BRCA1 mutation should undergo oophorectomy shortly after diagnosis.
Assuntos
Proteína BRCA1/genética , Proteína BRCA2/genética , Biomarcadores Tumorais/genética , Neoplasias da Mama/genética , Neoplasias da Mama/terapia , Mutação em Linhagem Germinativa , Neoplasias Ovarianas/prevenção & controle , Ovariectomia , Adulto , Idoso , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Canadá , Distribuição de Qui-Quadrado , Análise Mutacional de DNA , Feminino , Predisposição Genética para Doença , Humanos , Pessoa de Meia-Idade , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/mortalidade , Neoplasias Ovarianas/patologia , Ovariectomia/efeitos adversos , Ovariectomia/mortalidade , Fenótipo , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Estados Unidos , Adulto JovemRESUMO
OBJECTIVE: To compare the survival rates of women with BRCA associated breast cancer who did and did not undergo mastectomy of the contralateral breast. DESIGN: Retrospective analysis. SETTING: 12 cancer genetics clinics. PARTICIPANTS: 390 women with a family history of stage I or II breast cancer who were carriers of BRCA1 and BRCA2 mutations and initially treated with unilateral or bilateral mastectomy. 181 patients had mastectomy of the contralateral breast. Patients were followed for up to 20 years from diagnosis. MAIN OUTCOME MEASURE: Death from breast cancer. RESULTS: 79 women died of breast cancer in the follow-up period (18 in the bilateral mastectomy group and 61 in the unilateral mastectomy group). The median follow-up time was 14.3 years (range 0.1-20.0 years). At 20 years the survival rate for women who had mastectomy of the contralateral breast was 88% (95% confidence interval 83% to 93%) and for those who did not was 66% (59% to 73%). In a multivariable analysis, controlling for age at diagnosis, year of diagnosis, treatment, and other prognostic features, contralateral mastectomy was associated with a 48% reduction in death from breast cancer (hazard ratio 0.52, 95% confidence interval 0.29 to 0.93; P=0.03). In a propensity score adjusted analysis of 79 matched pairs, the association was not significant (0.60, 0.34 to 1.06; P=0.08). Based on these results, we predict that of 100 women treated with contralateral mastectomy, 87 will be alive at 20 years compared with 66 of 100 women treated with unilateral mastectomy. CONCLUSIONS: This study suggests that women who are positive for BRCA mutations and who are treated for stage I or II breast cancer with bilateral mastectomy are less likely to die from breast cancer than women who are treated with unilateral mastectomy. Given the small number of events in this cohort, further research is required to confirm these findings.