Discovering the causes of cancer and the means of prevention

# BCRA R Package

BCRA is an R package that projects absolute risk of invasive breast cancer according to NCI’s Breast Cancer Risk Assessment Tool (BCRAT) algorithm for specified race/ethnic groups and age intervals.

This package is to project absolute risk of invasive breast cancer according to NCI’s Breast Cancer Risk Assessment Tool (BCRAT) algorithm for specified race/ethnic groups and age intervals. The updated version 2.0 includes the new Hispanic model.

This package can be used to estimate the risk of developing breast cancer over a predetermined time interval with risk factors. As the same as Breast Cancer Risk Assessment SAS Macro, the users can specify the time interval as appropriate, not only limited to the 5 years risk prediction available with BCRAT.

The main function in this package is $absolute.risk$, which is defined based on a statistical model known as the "Gail model". Parameters and constants needed in this function include initial and projection age, recoded covariates using function $recode.check$, relative risks of BrCa at age "<50" and ">=50" obtained from function $relative.risk$ as well as other known constants listed from function $list.constants$ like BrCa composite incidences, competing hazards, 1-attributable risk using in NCI BrCa Risk Assessment Tool (NCI BCRAT). With risk factors and projection interval ages for a group of women, the function $absolute.risk$ will return the corresponding absolute risk projections. If the function returns any missing values, the function $error.table$ or $error.table.all$ is used to find where the errors occured. The function $check.summary$ can give a quick check for errors of input file and missing values of risks.  For further analysis, a data frame is created from the function $risk.summary$, which includes age, duration of the projection time interval, covariates and the projected risk.

The version 2.0 includes absolute risk projections for Hispanic women (US born and Foreign born) based on race specific RR risk models developed on the San Francisco Bay Area Breast Cancer Study (SFBCS). Race specific attributable risks, breast cancer composite incidences and competing hazards are added to the updated package.

Any changes/modifications to the package would be at the user’s own discretion and risk.