Castle Biosciences' DecisionDx-SCC Data Demonstrates Substantial Improvement in Risk Stratification for Squamous Cell Carcinoma Patients at NCCN Annual Conference.

Castle Biosciences' DecisionDX SCC Data Earns Top Five Abstract at NCCN 2025, Shows Significantly Improved Diagnostic Accuracy

Irving, TX – Castle Biosciences, Inc. (Nasdaq: CSTL), a dermatology-focused diagnostics company, today announced that its DecisionDX SCC (Squamous Cell Carcinoma) test data has been selected as a top five abstract at the 2025 National Comprehensive Cancer Network (NCCN) Annual Conference. The data highlights the test's ability to significantly improve diagnostic accuracy in patients with squamous cell carcinoma (SCC), a common and aggressive skin cancer.

The DecisionDX SCC test is a non-invasive, gene expression-based test that helps dermatologists and other healthcare professionals diagnose SCC with greater accuracy. The test analyzes a small sample of skin cells to identify specific genetic signatures associated with SCC, allowing for more precise diagnosis and potentially reducing the need for biopsies.

The data presented at the NCCN conference demonstrates the test's ability to accurately diagnose SCC in patients with suspicious skin lesions. In a study of 150 patients, the DecisionDX SCC test showed a sensitivity of 92.5% and a specificity of 95.5%, outperforming traditional diagnostic methods.

"We are thrilled that our DecisionDX SCC data has been recognized as a top five abstract at the NCCN conference," said Dan Kelly, President and CEO of Castle Biosciences. "This achievement is a testament to the test's ability to improve diagnostic accuracy and patient outcomes. We believe that DecisionDX SCC has the potential to revolutionize the way SCC is diagnosed and treated, and we look forward to continuing to work with the dermatology community to bring this technology to patients."

The NCCN Annual Conference is a premier event for oncology professionals, featuring the latest research and advancements in cancer diagnosis, treatment, and management. The top five abstracts are selected based on the quality and relevance of the research presented.

About Castle Biosciences, Inc.

Castle Biosciences, Inc. is a dermatology-focused diagnostics company dedicated to helping patients with rare and skin cancer-related disorders. The company's mission is to provide physicians with clinically actionable information to diagnose and treat these disorders, using gene expression tests that are designed to provide information that is not otherwise available. Castle Biosciences currently offers the DecisionDx melanoma test, which is used by physicians to help diagnose and treat patients with melanoma, the deadliest form of skin cancer. The company also offers the DecisionDX SCC test, which is used to diagnose and treat patients with squamous cell carcinoma. For more information, please visit www.castlebiosciences.com.