Nomograms for clinically localized prostate cancer. Part II: radiation therapy

Prostate cancer can be effectively treated with either external beam radiation techniques or with brachytherapy. This study was designed to address the methodology that is used to assess outcome data in the current radiation literature and to evaluate available nomograms that can be used to predict outcomes. A literature search was performed and 12 articles reviewed. Risk stratification was the most frequently used methodology to analyze data. This method encompasses disease-specific variables: the pretreatment prostate-specific antigen (PSA) value and the Gleason score are classified by using cut points into low, intermediate, and high-risk groups. Another methodology uses nomograms to predict outcome. The nomogram uses continuous values of each variable so that the outcome probability for a specific set of parameters is quite specific. The advantage of nomogram analysis over risk stratification analysis is presented. In conclusion, only 3 reports were identified in the radiation literature that used a nomogram to predict outcome. One of the nomograms is proprietary and difficult to interpret. The other 2 nomograms, 1 for 3-dimensional radiation and the other for brachytherapy, have been incorporated into hand-held devices that can be used at consultation with the patient to discuss outcome probabilities to assist in treatment decisions.