Background Estimates of an 80-90% risk of breast cancer for carriers of germline mutations in the BRCA1 and BRCA2 genes are based on studies of families at high risk of breast cancer.
Risk estimates for a population are possible if the mutation status of a representative sample of that population can be assessed.
In Iceland, one common founder BRCA2 mutation occurs in 0.6% of the population.
Iceland has a population-based cancer registry and a large collection of pedigrees, and estimation of cancer risk in mutation carriers is therefore possible.
Methods We studied 575 breast-cancer patients, 541 women and 34 men unselected for family history of breast cancer.
Data on cancer in first-degree relatives were available from the cancer registry.
Risk of cancer was estimated by comparing the history of cancer in first-degree relatives of carriers and non-carriers.
Findings 56 (10.4%) of the 541 women and 13 (38%) of the 34 men carried the 999del5 mutation.
The estimated risk of breast cancer at age 50 for all female carriers of the 999del5 mutation was 17.0% (95% Cl 9.1-25.9) and 37.2% (22.4-53.9) at age 70. interpretation The results of our population-based study show that the mean risk of breast cancer in carriers of mutation in BRCA2 is lower than previously suggested.
Individual risk assessment will, however, have to take account of family history.
Mots-clés Pascal : Carcinome, Glande mammaire, Facteur risque, Mutation, Lignée germinale, Etude longitudinale, Histoire familiale, Femelle, Homme, Islande, Iles Atlantiques, Tumeur maligne, Glande mammaire pathologie, Immunopathologie, Déterminisme génétique, BRCA2 mutation
Mots-clés Pascal anglais : Carcinoma, Mammary gland, Risk factor, Mutation, Germ line, Follow up study, Family story, Female, Human, Iceland, Atlantic Ocean Islands, Malignant tumor, Mammary gland diseases, Immunopathology, Genetic determinism
Notice produite par :
Inist-CNRS - Institut de l'Information Scientifique et Technique
Cote : 98-0504150
Code Inist : 002B20E02. Création : 19/02/1999.