Sumbal Umar, Zarmeen Shahid, Micheal O'Cathail, M Ananth Sivanandan
50 patients were identified with a mean age of 75 years (range: 44-94). 78% (n = 39) of the patients' primary lesion originated from the head and neck (H&N) region, whilst the remaining 22% (n = 11) had a primary lesion from other areas. No patients had received prior systemic treatment for a-cSCC. Overall, the disease control rate (DCR) was 74%, and the RR was 55.8% with complete response in 35% (n = 15), partial response in 21% (n = 9), and stable disease in 19% (n = 8). In patients with H&N primary site of disease, RR was 58.9% versus 27.2% in patients with non-H&N primary site of disease, with a p value of 0.027. The overall mean PFS for the study population was 27.3 months (95% CI: 21.2-33.5 months), with the median PFS not reached for the study duration. The median PFS for patients with H&N primary site of disease was not reached as compared to the median PFS of 4 months (95% CI: 2.2-5.7 months) for patients with non-H&N primary site of disease, with a p value of 0.049. The median OS for the study population was 34 months (95% CI: 15.4-52.5 months). Grade 3 toxicities were reported in 22% (n = 11) with no Grade 4 toxicites.
INTRODUCTION: Cemiplimab has been licensed for use in the United Kingdom as the sole immunotherapy agent for first-line use in advanced cutaneous squamous cell carcinoma (a-cSCC). Given that previous clinical trials leading to the approval of cemiplimab had relatively small patient cohorts with relatively short follow-up periods, with a large proportion of patients who had received prior systemic treatment, this retrospective real-world study sought to add further insight into survival and toxicity in patients who exclusively had received first-line use of cemiplimab, as well as comparing response rates (RRs) based on primary site location.
METHODS: This retrospective study identified patients diagnosed with a-cSCC between 01/08/2019 and 31/03/2024 who received cemiplimab as first-line treatment at our institution. Data to enable response assessment and toxicity were collected and analyzed.
RESULTS: 50 patients were identified with a mean age of 75 years (range: 44-94). 78% (n = 39) of the patients' primary lesion originated from the head and neck (H&N) region, whilst the remaining 22% (n = 11) had a primary lesion from other areas. No patients had received prior systemic treatment for a-cSCC. Overall, the disease control rate (DCR) was 74%, and the RR was 55.8% with complete response in 35% (n = 15), partial response in 21% (n = 9), and stable disease in 19% (n = 8). In patients with H&N primary site of disease, RR was 58.9% versus 27.2% in patients with non-H&N primary site of disease, with a p value of 0.027. The overall mean PFS for the study population was 27.3 months (95% CI: 21.2-33.5 months), with the median PFS not reached for the study duration. The median PFS for patients with H&N primary site of disease was not reached as compared to the median PFS of 4 months (95% CI: 2.2-5.7 months) for patients with non-H&N primary site of disease, with a p value of 0.049. The median OS for the study population was 34 months (95% CI: 15.4-52.5 months). Grade 3 toxicities were reported in 22% (n = 11) with no Grade 4 toxicites.
DISCUSSION: The use of cemiplimab as first-line treatment in a-cSCC demonstrates high efficacy and low rates of serious toxicity, which is especially reassuring in a patient cohort comprising of more elderly patients. The high complete RR seen in our patient cohort may reflect the exclusive first-line use of cemiplimab in our study, as per now established real-world practice in a-cSCC. Higher RRs and PFS are seen in patients with head/neck primary site of disease vs. non head/neck primary site, which should be evaluated further in future clinical trials.