Current and Future Role of Immunotherapy in Cutaneous Squamous Cell Carcinoma
Posted: Thursday, December 19, 2019
An Oral Oncology review article buoyantly concluded that checkpoint inhibition immunotherapy has revolutionized the treatment of patients with unresectable, locally advanced, or metastatic cutaneous squamous cell carcinoma. Coauthors Alexander Guminski, MD, PhD, and Brian Stein, MBBS (Hons), both of the University of Sydney in Australia, reported that tumors generally respond well to checkpoint inhibition therapy, with manageable toxicity. Of note, they added, “[they are] durable responses that can continue beyond cessation of treatment.” Chemotherapies, EGFR inhibitors, and interferons have also been used to treat cutaneous squamous cell carcinoma successfully, but often with more toxicity and less durability than checkpoint inhibitors.
Drs. Guminski and Stein pointed out that cutaneous squamous cell carcinoma represents a significant sector of incurable non-melanoma skin cancers, causing 1% of all cancer deaths. They posed the question, could checkpoint inhibition potentially be curative? In one trial, they highlighted, cemiplimab and pembrolizumab are being tested as adjuvant therapy for patients with high-risk resected disease. More broadly, checkpoint inhibition could potentially be used neoadjuvantly, “preceding definitive radiotherapy or surgery for locally advanced disease, to reduce the morbidity of resection and perhaps also to reduce the risk of recurrence.”
The majority of patients with cutaneous squamous cell carcinoma are older and often frail. “Immunotherapy in the fitter older patient does seem to have similar activity and toxicity as in younger patients,” according to Drs. Guminski and Stein. However, neither patients with autoimmune conditions and underlying or previously treated hematologic conditions, who represent a significant percentage of those with advanced cutaneous squamous cell carcinoma, nor those with solid organ transplants were included in the trials they assessed. The authors are confident that clinical trial data will be reported over the next several years “to guide [the] optimal use” of checkpoint inhibition in most populations.
Disclosure: The study authors reported no conflicts of interest.