Castle Biosciences to Present New Data Highlighting the Clinical Value of its Dermatologic Tests for Patients with Skin Cancer at the 2024 American Academy of Dermatology (AAD) Annual Meeting - Seite 2

DecisionDx-SCC

• Oral Poster Presentation Title: Consistent utilization of the 40-gene expression profile (40-GEP) test in high-risk cutaneous squamous cell carcinoma (cSCC) by clinicians according to intended use indications
• Presenter and Lead Author: Jane Yoo, M.D., Icahn School of Medicine at Mount Sinai, New York
• Abstract Number: 54153
• Date: March 9, 2024
• Time: 10:30-10:35 a.m. Pacific Time
• Location: San Diego Convention Center (Upper Level, Sails Pavilion, Poster Center 2)

Summary: This study provides summary metrics regarding DecisionDx-SCC (40-GEP) test results and patient risk factors for tumor samples clinically tested in the first three years of the test’s availability between September 2020 and August 2023 (n=16,930). The study data demonstrate that clinicians are utilizing the DecisionDx-SCC test appropriately for patients with high-risk cutaneous squamous cell carcinoma (SCC). These patients are at a higher risk of poor outcomes compared to the general SCC patient population, yet over 70% of patients received a Decision-SCC Class 1 test result, indicating they are at a lower biological risk for metastasis. Each DecisionDx-SCC Class result was present in the various subgroupings of risk factors in the study (patients with 1-2, 3-4 and more than 5 risk factors), demonstrating that the test provides independent risk assessment from clinicopathological presentation. These data support incorporating the test’s results into clinical practice to improve the accuracy of risk predictions to guide more personalized treatment plans for patients.

MyPath Melanoma

• ePoster Title: Enabling access to prognostic gene expression profile (GEP) testing for invasive melanoma by leveraging RNA-based testing in the diagnostic workflow
• Abstract Number: 52819

Summary: Reaching a definitive diagnosis of melanoma can be challenging. Ancillary testing can provide clarity and a definitive diagnosis for problematic lesions. The MyPath Melanoma (23-GEP) diagnostic test returns accurate results quickly, with approximately 80% of cases tested receiving an actionable result in a median of four business days. Between March 1 and July 31, 2023, approximately 60% of ambiguous lesions tested with MyPath received a benign test result, potentially reducing overdiagnosis and overtreatment for diagnostically challenging lesions. Lesions that receive a malignant test result (approximately 20% of lesions tested with MyPath in the five-month study timeframe) can be tested with the DecisionDx-Melanoma risk stratification test, using the same extracted tumor material when available, to inform risk-aligned decisions about sentinel lymph node biopsy, surveillance imaging and patient follow-up schedules. Approximately 80% of clinically tested lesions with a malignant MyPath result have sufficient biopsy tumor content for DecisionDx-Melanoma testing.