Impact of age and comorbidities on long-term survival of patients with high-risk prostate cancer treated with radical prostatectomy: a multi-institutional competing-risks analysis

Background: Survival after surgical treatment using competing-risk analysis has been previously examined in patients with prostate cancer (PCa). However, the combined effect of age and comorbidities has not been assessed in patients with high-risk PCa who might have heterogeneous rates of competing mortality despite the presence of aggressive disease.

Objective: To examine the risk of 10-yr cancer-specific mortality (CSM) and other-cause mortality (OCM) according to clinical and pathologic characteristics of patients treated with radical prostatectomy (RP) for high-risk PCa.

Design, setting, and participants: Within a multi-institutional cohort, 3828 men treated with RP for high-risk PCa (defined as the presence of at least one of these risk factors: prostate-specific antigen >20 ng/ml, biopsy Gleason score 8-10, clinical stage ≥ T3) were identified.

Intervention: All patients underwent RP and pelvic lymph node dissection.

Outcome measurements and statistical analysis: Competing-risk Poisson regression analyses were performed to simultaneously assess the 10-yr CSM and OCM rates after RP. The same analyses were also conducted after stratification of patients according to age at surgery, comorbidity status assessed by the Charlson Comorbidity Index (CCI), and number of risk factors (one vs two or more).

Results and limitations: Overall, 229 patients (5.9%) died from PCa; 549 (14.3%) died from other causes. The 10-yr CSM and OCM rates ranged from 5.1% to 12.8% and from 4.3% to 37.4%, respectively. Age and CCI were the major determinants of OCM; their impact on CSM was minimal. OCM was the leading cause of death in all patient groups except in young men (≤ 59 yr) with no comorbidities, regardless of the number of risk factors (10-yr CSM and OCM 6.9-12.8% and 5.5-6.3%, respectively). The main limitation was the lack of patients managed conservatively.

Conclusions: Even in the context of high-risk PCa, long-term CSM after RP is modest and represents the leading cause of death only in young, healthy patients. Conversely, older and sicker patients with multiple risk factors are at the highest risk of dying from OCM while sharing very low CSM rates.