Background

PD(L)1 Immunotherapy agents atezolizumab and pembrolizumab are in routine use in advanced urothelial cancers in previously treated patients. We report 4 institutions experience and outcomes using these immunotherapy agents in the advanced / metastatic urothelial cancer group across the South West Peninsula.

Method

Retrospective case review of all advanced / metastatic urothelial cancer patients treated with immunotherapy were identified by Aria systemic anti-cancer prescribing database up to 31/12/19 at The Royal Cornwall Hospital, Torbay Hospital, Royal Devon and Exeter Hospital and University Hospitals Plymouth. We looked at radiological responses overall survival, progression free survival and toxicities related to immunotherapy.

Results

There were 38 patients (31 male, 7 female) who had immunotherapy with a median age of 74 (45-87). Bladder = 27, Ureteric =11, 5 patients had first line therapy and 33 patients had received either 1 or 2 prior systemic therapies. Median overall survival was 38 weeks and median progression free survival is 10 weeks.

17 (44%) patients showed a radiological response to immunotherapy, including mixed/static/partial response. 82% of these responses were seen on the first scan at 3 months. 2 patients had pseudoprogression on first scan. 64% of patients who showed evidence of response were alive at 1 year vs 0% of non-responders. 1 patient completed 2 years of treatment at the time of writing.

There have been no treatment related deaths. The most common adverse event was G1-2 fatigue and G1-2 skin rash. Other toxicities included G1 Diarrhoea (4pts), Colitis (2pts) Hypothyroidism (6pts),hepatitis (2pt) and pneumonitis(1pt) . 30% of patients had treatment breaks to allow for toxicity resolution. 19% of patients stopped treatment due to toxicities. 65% of responders had toxicities vs 58% non-responders.

Conclusion

Immunotherapy is a successful treatment for patients with advanced urothelial cancers. Most responses are early (12 weeks) but it is difficult to discount the relatively rare pseudoprogression. Durable stabilisation of disease was evident in patients with evidence of response. More toxicities were seen in the response group but there may be overlap in signs of progression.

Impact statement