Radiotherapy before cemiplimab associated with progression-free survival
Click Here to Manage Email Alerts
Key takeaways:
- A significant correlation was found in patients treated with radiotherapy prior to cemiplimab.
- A ‘potential synergy’ could be explored with future research.
Prior radiotherapy was associated with progression-free survival in patients with metastatic cutaneous squamous cell carcinoma treated with cemiplimab, according to a study.
“Cutaneous squamous cell carcinoma (cSCC) is the second most prevalent skin cancer, with an estimated incidence of 30 [per] 100,000 inhabitants,” Valerio Nardone, MD, associate professor at the department of precision medicine at the University of Campania “L.Vanvitelli” in Naples, Italy, and colleagues wrote. “Although the majority of cSCC can be cured by surgery and radiotherapy, a subset of patients ranging from 1.9% to 4.6% develop disease recurrence or progression. The field of immunotherapy has recently witnessed a significant advancement, with the development of novel anticancer therapies such as anti-programmed cell death-1 receptor (anti-PD1) monoclonal antibodies, pembrolizumab [Keytruda, Merck] and cemiplimab [Libtayo, Regeneron], that have been approved for the treatment of locally advanced and metastatic cSCC.”
Nardone and colleagues conducted a retrospective study analyzing treatment patterns and outcomes of 45 patients (median age, 77 years; 73.3% men) with cSCC who were treated consecutively with cemiplimab.
Most patients (82.2%) presented with cSCC in the head and neck, with lower extremities (8.9%), the trunk (4.4%) and upper extremities (4.4%) following.
Upfront surgery was conducted in 73.3% of patients, whereas 57.8% underwent upfront radiotherapy. Radiotherapy was used as radical treatment in 18 (69.2%) of patients and as adjuvant therapy after surgery in eight (30.8%) patients. Local therapies including vismodegib (Erivedge, Genentech), photodynamic therapy and intralesional methotrexate were used in 11.1% of patients.
Mean progression-free survival (PFS) was 21.3 ± 2.2 months (95% CI, 16.9-25.7) and mean overall survival (OS) was 25.3 ± 2.1 months (95% CI, 21.2-29.4). Median PFS and median OS were not reached.
However, in patients who were treated with radiotherapy before cemiplimab, a univariate analysis found a correlation with PFS with no median PFS and a mean PFS of 24.6 ± 2.6 months (95% CI, 19.5-30), as compared with a median PFS of 10 months and a mean of 16.6 ± 3.6 months (95% CI, 9.5-23.7) in patients who did not undergo previous radiotherapy.
“The take-home message for clinicians is the potential synergy between immunotherapy and local therapies, particularly radiotherapy,” Nardone told Healio. “These two techniques may be used together in the future to enhance the therapeutic outcomes for patients with cSCC.”
A phase 3 trial that will explore cemiplimab in patients treated with surgery and adjuvant radiotherapy is currently enrolling patients.
“The clinical implications of this study are not yet definitive, as we still need to demonstrate the effectiveness of combining ionizing radiation with immunotherapy in this setting,” Nardone added. “These findings need to be validated in prospective studies, which we are currently undertaking. Future research should aim to include larger patient cohorts and control for potential biases inherent in retrospective analyses.”