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Medline ® Abstract for Reference 79

of 'Prevalence of BRCA1 and BRCA2 mutations and associated cancer risks'

Incidence of colorectal cancer in BRCA1 and BRCA2 mutation carriers: results from a follow-up study.
Phelan CM, Iqbal J, Lynch HT, Lubinski J, Gronwald J, Moller P, Ghadirian P, Foulkes WD, Armel S, Eisen A, Neuhausen SL, Senter L, Singer CF, Ainsworth P, Kim-Sing C, Tung N, Llacuachaqui M, Chornokur G, Ping S, Narod SA, Hereditary Breast Cancer Study Group, Ginsburg O, Maehle L, Sweet K, Gilchrist D, Olopade OI, Couch F, Isaacs C, Karlan B, Eng C, Weitzel JN, Daly MB, Garber JE, Zakalik D, Cullinane CA, Stoppa-Lyonnet D, Saal H, Meschino W, McKinnon W, Wood M, Fallen T, Kurz R, Manoukian S, Rosen B, McCuaig J, Demsky R, Lemire E, McLennan J, Panchal S, Chudley AE, Vadaparampil ST, Pal T, Rayson D, Valentini A, Friedman S, Cybulski C, Byrski T, Huzarski T
Br J Cancer. 2014 Jan;110(2):530-4. Epub 2013 Nov 28.
Background:The BRCA1 and BRCA2 genes confer increased susceptibility to breast and ovarian cancer and to a spectrum of other cancers. There is controversy regarding the risk of colorectal cancer conferred by germline mutations in these two genes.Methods:We followed 7015 women with a BRCA mutation for new cases of colorectal cancer. Incidence rates in carriers were compared with population-specific incidence rates, and standardised incidence ratios (SIRs) were estimated. The expected numbers of cancers were computed by multiplying person-years at risk by the appropriate age-, sex- and country-specific incidence rates from the five countries.Results:Twenty-one incident colorectal cancer cases were observed among all mutation carriers, compared with 23.6 cases expected. The SIR for BRCA1 carriers was 0.92 (95% confidence interval (CI), 0.54-1.40, P=0.7) and for BRCA2 carriers was 0.82 (95% CI, 0.30-1.81, P=0.7). The SIR for colon cancer was 3.81 (95% CI 1.77-7.23) for women below the age of 50 years (both genes combined) and was 0.60 (95% CI 0.33-1.00) for women aged 50 years and above.Conclusion:The risk of colorectal cancer is increased in female carriers of BRCA1 mutations below the age of 50 years but not in women with BRCA2 mutations or in older women.
Department of Cancer Epidemiology, Moffitt Cancer Center, 12902 Magnolia Drive, Tampa, FL 33647, USA.