In the field of melanoma, GEP tests are currently being utilized to identify high-risk patients and determine their need to receive adjuvant radiation, chemotherapy, and other forms of therapy.12 These tests are impacting physician management decisions for melanoma patients. The present study shows that GEP testing has the potential to improve clinical decision-making for cSCC cases as well.
More than one third of participants stated they did not use any system to stage their cSCC patients. This represents a clear knowledge gap and opportunity to improve clinical practice. The cSCC-GEP test may act as an additional piece of information, that in combination with a traditional staging system such as AJCC, could better optimize patient outcomes. A previous study of GEP in melanoma showed that adding GEP results to AJCC staging had an additive positive effect on prognostic accuracy.13 Future studies are warranted to determine if the cSCC-GEP test can have a similar impact.
A new immune therapy, Cemiplimab (PD-1 inhibitor), has been FDA-approved and shown to be efficacious for management of metastatic and locally advanced cSCC.10 Current staging systems are mainly histologic in nature, and genomic testing may more effectively identify high risk cases that would benefit from treatment with Cemiplimab. cSCC-GEP testing can aid in targeting this expensive therapy to high risk patients, while minimizing adverse effects for patients with lower risk disease who may not benefit from the drug.
Limitations to this study include the possibility that the clinical vignettes used are not complete representations of real-world patient cases. Moreover, this study used a cross sectional design and therefore, the results cannot be used to make inferences about causation. Additionally, the sample of dermatologists attending the national conference may not accurately represent the larger population of dermatologists practicing across the United States.
Funding Source: The National Society for Cutaneous Medicine (a 501(c)3 not-for-profit entity) funded this study. The group has received unrestricted educational grants from Castle Biosciences Inc.
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8. Schmults CD, Arron S, Wyson A, et al. A multi-gene risk signature for improved identification of cutaneous squamous cell carcinoma (cSCC) patients with a high risk of recurrence. Poster presented at: American Society of Clinical Oncology; June 5, 2018; Chicago, IL.
9. Que SKT, Zwald FO, Schmults CD. Cutaneous squamous cell carcinoma: