New Data at ASCO 2025 Affirms DecisionDx®-Melanoma's Ability to Improve Upon Staging-Based Risk Stratification and Predict Survival Outcomes

Study results show that DecisionDx-Melanoma was associated with a 32% reduction in mortality risk compared to untested patients

FRIENDSWOOD, Texas, May 29, 2025 (GLOBE NEWSWIRE) -- Castle Biosciences, Inc. (Nasdaq: CSTL), a company improving health through innovative tests that guide patient care, will present novel research aimed at enhancing the clinical management of patients with cutaneous melanoma (CM) and uveal melanoma (UM) at the 2025 American Society of Clinical Oncology (ASCO) Annual Meeting, being held May 30-June 3, 2025, in Chicago. This includes the latest findings from Castle's ongoing collaboration with the National Cancer Institute's Surveillance, Epidemiology and End Results (NCI's SEER) Program Registries affirming the significant, independent risk stratification provided by DecisionDx-Melanoma in an expanded, real-world cohort of more than 13,500 patients who received the test as part of their melanoma care.

"Management decisions for melanoma patients, such as referrals for sentinel lymph node biopsy and surveillance intensity, are guided by a patient's risk of dying from their disease,” said Merve Hasanov, M.D., oncologist and director of the division of medical oncology at The Ohio State University Comprehensive Cancer Center in Columbus, Ohio. “The findings being presented at ASCO demonstrate that the DecisionDx-Melanoma test can provide more precise mortality risk predictions based on a patient's unique tumor biology and can improve upon the population-based risk assessment provided by American Joint Committee on Cancer (AJCC) staging. This can, in turn, help clinicians tailor treatment approaches to individual patient needs.”

Castle’s presentations at ASCO will take place during the Melanoma/Skin Cancers poster session on Sunday, June 1, from 9 a.m. to 12 p.m. Central time in Hall A – Posters and Exhibits.

• Title: The 31-gene expression profile can guide better risk-aligned care decisions for patients with stage I–III cutaneous melanoma: an NCI-SEER analysis
• Abstract: 9573
• Poster Bd #: 56
• Lead Author: Merve Hasanov, M.D., oncologist and director of the division of medical oncology at The Ohio State University Comprehensive Cancer Center, Columbus, Ohio
• Study highlights: This study presents an updated validation of the DecisionDx-Melanoma test's ability to independently stratify CM patients' mortality risk within AJCC sub-stages (stages I-IIA, IIB-C and III) as part of Castle's ongoing collaboration with the NCI’s SEER Program Registries. In this large, real-world cohort of 13,560 patients with CM – the largest real-world study of gene expression profile testing to date – the test provided significant risk stratification within the AJCC sub-groups (p