FRIENDSWOOD, Texas–(BUSINESS WIRE)–Castle Biosciences, Inc. (Nasdaq: CSTL), a company that improves health through innovative tests that guide patient care, today announced new data showing DecisionDx-SCC can independently stratify risk patients with cutaneous squamous cell carcinoma (SCC) and one or more risk factors based on their biological risk of metastasis, consistent with results from previous development and validation studies.1.2 The poster was presented at the 2022 Annual Meeting of the American College of Mohs Surgery (ACMS).

DecisionDx-SCC is Castle’s 40-gene expression profile (GEP) prognostic test designed to use a patient’s tumor biology to predict individual risk of metastasis in patients diagnosed with SCC who present with one or more high risk factors. The test classifies patients into one of three classes based on their biological risk of metastasis: Class 1 (low risk), Class 2A (moderate risk) or Class 2B (high risk).

“Identifying patients who are at increased risk for disease progression and metastasis is a challenge for clinicians who may see hundreds of cases of cutaneous squamous cell carcinoma in their practice each year,” said the study author. Sarah T. Arron, MD, Ph.D., Mohs surgeon and dermatologist at Peninsula Dermatology in Burlingame, CA. “Using DecisionDx-SCC to add a patient’s biological risk to our existing clinical and pathological risk assessment methods can improve our decision-making and help us personalize treatment for our patients.”

The poster, titled “Performance of the prognostic 40-gene expression profile (40-GEP) test for high-risk cutaneous squamous cell carcinoma (cSCC) in a second Independent cohort,” highlights data from a second multicenter study independent high-risk SCC patients, consisting of 598 new patient samples from 43 contributing centers. The poster is visible here. With the patient cohort from this study, combined with the patient cohort from the first validation study (n=420), the ability of DecisionDx-SCC to independently stratify risk was confirmed in a total of 1018 patients.

Kaplan-Meier analysis showed a statistically significant difference in metastasis-free survival (MFS) rates between DecisionDx-SCC Class 1, Class 2A and Class 2B results (p

Overall, the study data confirms what previous development and validation studies1.2 have justified: DecisionDx-SCC can accurately classify the risk of metastasis in patients with SCC with one or more risk factors and provides meaningful prognostic information independent of current risk prediction methods. Additionally, the study data further supports the use of DecisionDx-SCC test results in combination with other risk assessment and staging systems to guide more refined and risk-aligned patient care.

About DecisionDx®-SCC

DecisionDx-SCC is a 40-gene expression profile test that uses an individual patient’s tumor biology to predict the individual risk of cutaneous squamous cell carcinoma metastasis in patients with one or more risk factors. The outcome of the test, in which patients are stratified into a class 1 (low), 2A (moderate) or 2B (high) risk category, predicts individual metastatic risk to inform risk-tailored management.

Peer-reviewed publications have demonstrated that DecisionDx-SCC is an independent predictor of metastatic risk and that integrating DecisionDx-SCC with current prognostic methods can add positive predictive value to clinicians’ decisions regarding staging and management .

You can find more information about the test and the disease at www.CastleTestInfo.com.

About Castle Biosciences

Castle Biosciences (Nasdaq: CSTL) is a leading diagnostics company that improves health through innovative tests that guide patient care. The Company aims to transform disease management by putting people first: patients, clinicians, employees and investors.

Castle’s current portfolio includes tests for skin cancers, uveal melanoma, Barrett’s esophagus and mental health issues. Additionally, the Company has active research and development programs for testing in other diseases of high clinical need, including its test in development to predict systemic therapeutic response in patients with moderate to severe psoriasis, atopic dermatitis and related conditions. To learn more, please visit www.CastleBiosciences.com and join us on LinkedIn, Facebook, Twitter and instagram.

DecisionDx-Melanoma, DecisionDx-CMSeqDecisionDx-SCC, myPath Melanoma, DecisionDx DiffDx-Melanoma, DecisionDx-UM, DecisionDx-PRAME, DecisionDx-UMSeqTissueCypher and IDgenetix are registered trademarks of Castle Biosciences, Inc.

Forward-looking statements

This press release contains forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended, which are subject to the “sphere of security” created by these sections. These forward-looking statements include, but are not limited to, statements regarding: DecisionDx-SCC’s ability to accurately and independently stratify the risks of patients with cutaneous SCC and one or more risk factors, to improve clinical decision-making by helping clinicians personalize treatment for their patients and add clinical value when used alongside other risk prediction systems. The word “may” and similar expressions are intended to identify forward-looking statements, although not all forward-looking statements contain such identifying words. We may not actually achieve the plans, intentions or expectations disclosed in our forward-looking statements, and you should not place undue reliance on our forward-looking statements. Actual results or events could differ materially from the plans, intentions and expectations disclosed in the forward-looking statements we make. These forward-looking statements involve risks and uncertainties that could cause our actual results to differ materially from those contained in the forward-looking statements, including, without limitation: the effects of the COVID-19 pandemic on our business and our efforts to address its impact on our business; the results and conclusions of subsequent studies or trials may contradict the results and conclusions of earlier studies or trials or may not support the results obtained in this study, including with respect to the discussion of DecisionDx -SCC in this press release; the actual application of our tests may not provide the above benefits to patients; and the risks set forth under “Risk Factors” in our Quarterly Report on Form 10-Q for the three months ended March 31, 2022, and in our other filings with the SEC. Forward-looking statements speak only as of the date they are made, and we assume no obligation to update forward-looking statements except as required by law.

1Wysong, A, Newman J, Covington K et al. Validation of a 40-gene expression profile test to predict metastatic risk in localized high-risk cutaneous squamous cell carcinoma. DAD 2021; 361-368. do I: https://doi.org/10.1016/j.jaad.2020.04.088

2Ibrahim S, Kasprzak J, Hall M et al. Improved assessment of metastatic risk in cutaneous squamous cell carcinoma with the 40-gene expression profile test. Future Oncology 2021. do I: https://doi.org/10.2217/fon-2021-1277