No evidence of excess breast cancer risk among mutation-negative women from BRCA mutation-positive families.
Breast Cancer Res Treat
; 125(1): 169-73, 2011 Jan.
Article
en En
| MEDLINE
| ID: mdl-20458532
ABSTRACT
This analysis addresses risk of breast cancer among women in BRCA-positive families who test negative for the family mutation. We compared the number of prospectively diagnosed breast cancers in 395 mutation-negative women from 28 BRCA1/2-positive families to an age-, race-, and calendar time-specific expected number of breast cancers derived from the SEER 9 Cancer Registry. Study participants contributed a total of 7008.1 person-years of follow-up. The mean age at study entry was 31.3 years; mean follow-up was 17.7 years. Ten women developed breast cancer yielding an observed-to-expected ratio of 0.82 (95% CI 0.39-1.51). Adjustment for possible reduction in breast cancer risk due to oophorectomy by two different methods resulted in O/E ratios in the range of 0.80-0.99. Stratification by degree of relatedness to the nearest mutation carrier did not substantially alter these results, however, women with at least one-first degree relative with breast cancer appeared to have a slightly increased, though not statistically significant, risk of breast cancer (O/E ratio = 1.33, 95% CI 0.41-2.91). Our data suggest that breast cancer risk among mutation-negative women from BRCA1/2 mutation-positive families is similar to that observed in the general population, with a possible slight increase in risk among mutation-negative women with a family history of breast cancer in a first degree relative. Although this is the largest prospective cohort yet assembled to address this important question, the number of breast cancer events is still relatively small.
Texto completo:
1
Banco de datos:
MEDLINE
Asunto principal:
Neoplasias de la Mama
/
Proteína BRCA1
/
Proteína BRCA2
/
Mutación
Tipo de estudio:
Etiology_studies
/
Observational_studies
/
Risk_factors_studies
Límite:
Adult
/
Female
/
Humans
/
Middle aged
País/Región como asunto:
America do norte
Idioma:
En
Revista:
Breast Cancer Res Treat
Año:
2011
Tipo del documento:
Article
País de afiliación:
Estados Unidos