A Stage-for-Stage and Grade-for-Grade Analysis of Cancer-Specific Mortality Rates in Renal Cell Carcinoma According to Age: A Competing-Risks Regression Analysis

BackgroundThe association of advanced age and cancer control outcomes shows discordant findings.ObjectiveTo evaluate the effect of age on cancer control outcomes in a large population-based cohort of patients diagnosed with renal cell carcinoma (RCC) of all stages.Design, setting, and participantsUsing the Surveillance Epidemiology and End Results database, 36 333 patients with RCC were identified. The population was stratified according to age: < 50, 50–59, 60–69, 70–79, and ≥80 yr. The effect of age on cancer control outcomes was evaluated using competing-risks regression models. Analyses were repeated stage for stage and grade for grade.MeasurementsCancer-specific mortality (CSM) was measured.Results and limitationsAge categories 50–59, 60–69, 70–79, and ≥80 yr respectively portended a 1.4-, 1.5-, 1.6-, and 1.9-fold higher risk of CSM than age category <50 yr (all p < 0.001). The effect of advanced age was particularly detrimental in patients with stage I disease: 1.8-, 2.3-, 3.2-, and 3.8-fold higher CSM risk for the same age groups, respectively (all p < 0.001). The effect of age on CSM was at its peak in patients with stage I, low-grade RCC (1.6-, 2.2-, 3.6-, and 4.3-fold, respectively; all p < 0.001) and remained elevated in stage I, high-grade RCC (2.2-, 2.6-, 2.4-, and 3.0-fold higher, respectively; all p < 0.05). Conversely, its effect was virtually absent in patients with stage II–IV RCC.ConclusionsOur data suggest that stage I RCC may behave in a more aggressive fashion in elderly patients. Further studies are required to confirm the current findings.