e16101 Background: Checkpoint-inhibitors have recently been introduced in the treatment of patients with genitourinary cancers. However, the use in elderly patients is controversial due to putative age-associated changes including the dysregulation of the immune system. We sought to investigate the safety and efficacy of immunotherapy in patients younger and older than 75 years of age. Methods: We conducted a retrospective review of patients with renal cell carcinoma and urothelial cancer treated with different immunotherapeutic agents between August 2015 and September 2018 at a high-volume single institution. Eligible patients received at least one cycle of single agent or a combination of checkpoint inhibitors as first or following treatment line. Immune-related adverse events (irAE) were graded using the NCI CTCAE v 4.0. Clinicopathological parameters including gender, cancer entity, ECOG, adverse events, comorbidities and response to treatment were stratified by age ≥ 75 vs. < 75 years and tested with a Pearson's chi-squared test. Additionally, we evaluated the impact of irAE on oncological outcome using the log-rank test. Results: 79 patients were identified, of those 27 (34.2%) were 75 years and older (15 renal cell carcinoma and 12 urothelial cancer patients) and 52 (65.8%) were younger than 75 years (39 renal cell carcinoma and 13 urothelial cancer patients). 2 complete responses were achieved in the elderly group and 6 in the younger group (p = 0.56). Disease control rate (stable disease, partial and complete response) was 48,1% in the elderly group and 53.8% in the younger group (p = 0.631). We observed a total of 30 irAEs (18 grade 1-2 and 12 grade 3-4), with an even distribution among the groups (≥75 years: 1 grade 4 AE; < 75 years: 12 grade 3-4 AEs). Except for ECOG ≥2 (p = 0.009) and ≥2 comorbidities (p < 0.001), there was no difference when groups were stratified by age. Both disease control rate and irAE did not differ between age subgroups. Occurrence of irAE showed no impact on oncological survival. Conclusions: The study demonstrates that patients over 75 years of age with renal cell and urothelial cancer treated with checkpoint-inhibitors respond with a good toxicity profile and an efficacy comparable with the younger population. irAE seem to have no impact on prognosis.
