PD-1 inhibition therapy for advanced cutaneous squamous cell carcinoma: a retrospective analysis from the University of Southern California.

Abstract

PURPOSE:

Approximately 5% of patients with cutaneous squamous cell carcinoma (CSCC) may develop recurrent or metastatic disease. The management of such cases is challenging and requires multi-disciplinary care. Immunotherapy using PD-1 inhibition was approved to treat unresectable or metastatic CSCC in 2018. Given limited data regarding clinical outcomes outside of published trials, we describe our experience using this therapy.

METHODS:

We retrospectively reviewed all patients treated with PD-1 inhibition as therapy for locally advanced, regionally metastatic or distant metastatic CSCC at the University of Southern California. Clinicopathological characteristics, treatment data using PD-1 inhibitors, and outcomes were assessed.

RESULTS:

Among 26 patients treated with PD-1 inhibition, the objective response rate was 42.3%, with 19.2% of patients having partial response and 23.1% having complete response to therapy. The median progression-free survival was 5.4 months. Median tumor mutational burden (TMB) was higher among responders compared to non-responders (60 vs. 9 Mut/Mb, p = 0.04). Primary CSCC tumor location on the head/neck was also associated with response to PD-1 inhibition (p = 0.04). Two patients with mutations affecting mismatch repair deficiency were noted to have complete response to treatment. No other variables were associated with treatment outcomes.

CONCLUSION:

PD-1 inhibition produces durable responses among patients with advanced or metastatic CSCC. PD-1 inhibition therapy is well tolerated, but patients should be monitored closely for immune-related adverse events, particularly frail or immune-suppressed patients. Further investigation of potential biomarkers to help identify patients who will derive the most benefit from this therapeutic option is needed.

• Authors: Gino K In, Poorva Vaidya, Alexandra Filkins, David J Hermel, Kevin G King, Omar Ragab, William W Tseng, Mark Swanson, Niels Kokot, Julie E Lang, Lawrence Menendez, Brittney DeClerck, Gene Kim, Jenny C Hu, Alicia Terando, Hossein Jadvar, Charité Ricker, Kimberly A Miller, David H Peng, Ashley Wysong
• Journal: Journal of cancer research and clinical oncology (J Cancer Res Clin Oncol) Vol. 147 Issue 6 Pg. 1803-1811 (Jun 2021) ISSN: 1432-1335 [Electronic] Germany
• PMID: 33210210 (Publication Type: Journal Article)

Chemical References

• Immune Checkpoint Inhibitors

Topics

• Adult
• Aged
• Aged, 80 and over
• California (epidemiology)
• Carcinoma, Squamous Cell (diagnosis, drug therapy, mortality, pathology)
• Disease Progression
• Female
• Humans
• Immune Checkpoint Inhibitors (therapeutic use)
• Male
• Middle Aged
• Neoplasm Metastasis
• Progression-Free Survival
• Retrospective Studies
• Skin Neoplasms (diagnosis, drug therapy, mortality, pathology)
• Treatment Outcome
• Young Adult