This model can be used to predict the pre-test probability (prior probability)
that a person has a BRCA1 or BRCA2 mutation. Other models exist,
which may provide different estimates.
This model does not predict breast cancer risk. It focuses only on the chance that an individual has
inherited a mutation in BRCA1 or BRCA2.
Decisions regarding genetic testing typically include consideration of personal
and family history of cancer, national and/or professional group recommendations
(e.g., NCCN, USPSTF), insurance criteria and/or patient preferences, in addition
to pre-test probability estimates such as provided by this model.
The Penn II Risk Model is an empirical model validated in families with multiple cases of breast and/or ovarian cancer.
All families included in the model development had two or more individuals affected with either breast and/or ovarian cancer
and one affected individual had to be a first, second or third degree relative of the other affected individual.
As such, results in families with single cases of breast or ovarian cancer need to be interpreted with caution.
This model was not designed to determine eligibility for multi-gene panel testing for hereditary cancer risk, rather
the prior probability that an individual has a BRCA1 or BRCA2 pathogenic variant.
References:
Lindor, N.M., Johnson, K.J., Harvey, H. et al. Predicting BRCA1 and BRCA2 gene mutation carriers: comparison of PENN II
model to previous study. Familial Cancer 9, 495-502 (2010)
https://doi.org/10.1007/s10689-010-9348-3
Panchal, S.M., Ennis, M., Canon, S. et al. Selecting a BRCA risk assessment model for use in a familial cancer clinic.
BMC Med Genet 9, 116 (2008).
https://doi.org/10.1186/1471-2350-9-116