Non-metastatic muscle-invasive bladder cancer: the role of age in receiving treatment with curative intent

Abstract

OBJECTIVES: To evaluate which patient and tumour characteristics are associated with remaining untreated in patients with potentially curable, non-metastatic muscle-invasive bladder cancer (MIBC), and to compare survival of untreated vs treated patients with similar characteristics. PATIENTS AND METHODS: For this cohort study, 15 047 patients diagnosed with cT2-T4aN0/xM0/x urothelial MIBC between 2005 and 2019 were identified in the Netherlands Cancer Registry. Factors associated with remaining untreated were identified using logistic regression analyses. Interhospital variation was assessed using multilevel analysis. Using a propensity score, the median overall survival (mOS) of untreated and treated patients was evaluated. Analyses were stratified by age (<75 vs ≥75 years). RESULTS: One-third of patients aged ≥75 years remained untreated; increasing age, worse performance status, worse renal function, cT4a stage and previous radiotherapy in the abdomen/pelvic area increased the odds of remaining untreated. One in 10 patients aged <75 years remained untreated; significant associations were only found for performance status, renal function and cT4a stage. Interhospital variation for remaining untreated was largest for patients aged ≥75 years, ranging from 37% to 69% (case-mix-adjusted). Irrespective of age, mOS was significantly worse for untreated patients: 6.4 months (95% confidence interval [CI] 5.1-7.3) vs 16.0 months (95% CI 13.5-19.1) for treated patients. CONCLUSION: On average, one in five patients with non-metastatic MIBC remained untreated. Untreated patients were generally older and had a more unfavourable prognostic profile. Untreated patients had significantly worse overall survival, regardless of age. Age alone should therefore not affect treatment decision-making. Considering the large interhospital variation, a proportion of untreated patients might be wrongfully denied life-prolonging treatment.