Genetic variants add little to breast cancer risk prediction

January 01, 0001

Genetic variants add little to breast cancer risk prediction

These US authors used information on traditional risk factors and 10 common genetic variants associated with breast cancer in 5590 case subjects and 5998 control subjects, 50 to 79 years of age, from four US cohort studies and one case-control study from Poland to fit models of the absolute risk of breast cancer. With the use of receiver-operating-characteristic curve analysis, they calculated the area under the curve (AUC) as a measure of discrimination. They calculated the fraction of case subjects in quintiles of estimated absolute risk after the addition of genetic variants to the traditional risk model.

They found: "The AUC for a risk model with age, study and entry year, and four traditional risk factors was 58.0%. With the addition of 10 genetic variants, the AUC was 61.8%. About half the case subjects (47.2%) were in the same quintile of risk as in a model without genetic variants; 32.5% were in a higher quintile, and 20.4% were in a lower quintile."

The authors concluded: "The inclusion of newly discovered genetic factors modestly improved the performance of risk models for breast cancer. The level of predicted breast-cancer risk among most women changed little after the addition of currently available genetic information."

Determination of these genetic factors does not appear to add clinically significant risk information.

For the full abstract, click here.

N Engl J Med 362:986-993, 18 March 2010
© 2010 to the Massachusetts Medical Society
Performance of Common Genetic Variants in Breast-Cancer Risk Models. Sholom Wacholder, Patricia Hartge, Ross Prentice, et al. Correspondence to Dr. Wacholder: [email protected]

Category: W. Pregnancy, Childbirth, Family Planning. Keywords: breast cancer, risk prediction, risk factors, genetic variants, risk modeling, journal watch.
Synopsis edited by Dr Linda French, Toledo, Ohio. Posted on Global Family Doctor 30 March 2010 2010

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