Validation of an Age-adjusted Prostate Cancer-Specific Comorbidity Index.

Abstract

Estimating competing mortality is of paramount importance for prostate cancer screening candidates and men with early prostate cancer. An age-adjusted prostate cancer-specific comorbidity index (PCCI) was developed recently for this purpose in an unselected population of 1598 men. We validated this mortality index in a sample of 2961 patients who consecutively underwent radical prostatectomy between 1992 and 2007 at our institution. In patients with a PCCI of 0, 1-2, 3-4, 5-6, 7-9, and ≥10 who were selected for radical prostatectomy, the 10-yr competing mortality rates were 2%, 9%, 17%, 27%, 56%, and 0% (n=3), respectively, compared with 10%, 19%, 35%, 60%, 79%, and 99%, respectively, in the unselected development cohort. The PCCI is well suited to stratify patients with prostate cancer according to their risk of competing mortality. In candidates for radical prostatectomy, however, the 10-yr competing mortality rates are approximately half as high as in unselected patients with the same PCCI risk level. With stratification by the age-adjusted prostate cancer-specific comorbidity index, the 10-yr competing mortality rate in men selected for radical prostatectomy is approximately half as high as in unselected patients at the same level of comorbid risk.