New Data at AACR Annual Meeting Highlights Use of DecisionDx®-Melanoma to Identify Early-Stage Melanoma Patients at High Risk of Distant Metastasis
Castle Biosciences (CSTL) presented new research data at the AACR Annual Meeting 2025 focusing on their DecisionDx tests for melanoma patients. The study of DecisionDx-Melanoma (n=1,661) showed that patients with Class 2B results had significantly higher distant metastasis rates compared to Class 1A across multiple sites: CNS (7.4% vs 0.9%), lung (7.4% vs 1.2%), liver (4.5% vs 0.6%), and bone (3.0% vs 0.8%).
Additionally, research on DecisionDx-UM for uveal melanoma revealed that among 79 patients, 72% were classified as low risk (Class 1) and 28% as high risk for metastasis. The study identified significant protein differences in aqueous humor samples between risk classes (N=386, p<0.0001), potentially enabling earlier detection and intervention for uveal melanocytic tumors.
Castle Biosciences (CSTL) ha presentato nuovi dati di ricerca al Meeting Annuale AACR 2025, concentrandosi sui test DecisionDx per i pazienti con melanoma. Lo studio su DecisionDx-Melanoma (n=1.661) ha evidenziato che i pazienti con risultati di Classe 2B presentavano tassi di metastasi a distanza significativamente più elevati rispetto alla Classe 1A in diversi siti: SNC (7,4% vs 0,9%), polmone (7,4% vs 1,2%), fegato (4,5% vs 0,6%) e ossa (3,0% vs 0,8%).
Inoltre, la ricerca su DecisionDx-UM per il melanoma uveale ha mostrato che, su 79 pazienti, il 72% è stato classificato a basso rischio (Classe 1) e il 28% ad alto rischio di metastasi. Lo studio ha identificato differenze significative nelle proteine dei campioni di umore acqueo tra le classi di rischio (N=386, p<0,0001), aprendo la possibilità a una diagnosi e un intervento più precoci per i tumori melanocitici uveali.
Castle Biosciences (CSTL) presentó nuevos datos de investigación en la Reunión Anual AACR 2025, centrados en sus pruebas DecisionDx para pacientes con melanoma. El estudio de DecisionDx-Melanoma (n=1.661) mostró que los pacientes con resultados de Clase 2B tenían tasas significativamente más altas de metástasis a distancia en comparación con la Clase 1A en varios sitios: SNC (7,4% vs 0,9%), pulmón (7,4% vs 1,2%), hígado (4,5% vs 0,6%) y hueso (3,0% vs 0,8%).
Además, la investigación sobre DecisionDx-UM para melanoma uveal reveló que de 79 pacientes, el 72% fue clasificado como bajo riesgo (Clase 1) y el 28% como alto riesgo de metástasis. El estudio identificó diferencias significativas en proteínas en muestras de humor acuoso entre las clases de riesgo (N=386, p<0,0001), lo que podría permitir una detección e intervención más tempranas para tumores melanocíticos uveales.
Castle Biosciences (CSTL)는 2025년 AACR 연례회의에서 흑색종 환자를 위한 DecisionDx 검사에 관한 새로운 연구 데이터를 발표했습니다. DecisionDx-Melanoma 연구(n=1,661)에서 클래스 2B 결과를 가진 환자들은 여러 부위에서 클래스 1A에 비해 원격 전이율이 유의하게 높게 나타났습니다: 중추신경계(7.4% vs 0.9%), 폐(7.4% vs 1.2%), 간(4.5% vs 0.6%), 뼈(3.0% vs 0.8%).
또한, 포도막 흑색종을 위한 DecisionDx-UM 연구에서는 79명의 환자 중 72%가 저위험군(클래스 1), 28%가 고위험군으로 분류되었습니다. 연구는 위험군 간에 수방액 샘플에서 유의한 단백질 차이를 확인했으며(N=386, p<0.0001), 이는 포도막 멜라닌 세포 종양의 조기 발견 및 개입 가능성을 제시합니다.
Castle Biosciences (CSTL) a présenté de nouvelles données de recherche lors de la réunion annuelle AACR 2025, axées sur leurs tests DecisionDx pour les patients atteints de mélanome. L'étude sur DecisionDx-Melanoma (n=1 661) a montré que les patients avec des résultats de Classe 2B présentaient des taux de métastases à distance significativement plus élevés que ceux de la Classe 1A dans plusieurs sites : SNC (7,4 % contre 0,9 %), poumon (7,4 % contre 1,2 %), foie (4,5 % contre 0,6 %) et os (3,0 % contre 0,8 %).
De plus, la recherche sur DecisionDx-UM pour le mélanome uvéal a révélé que parmi 79 patients, 72 % étaient classés à faible risque (Classe 1) et 28 % à haut risque de métastases. L'étude a identifié des différences protéiques significatives dans les échantillons d’humeur aqueuse entre les classes de risque (N=386, p<0,0001), ce qui pourrait permettre une détection et une intervention plus précoces pour les tumeurs mélanocytaires uvéales.
Castle Biosciences (CSTL) präsentierte neue Forschungsdaten auf dem AACR Jahreskongress 2025, die sich auf ihre DecisionDx-Tests für Melanompatienten konzentrieren. Die Studie zu DecisionDx-Melanoma (n=1.661) zeigte, dass Patienten mit Klasse 2B-Ergebnissen signifikant höhere Fernmetastasierungsraten im Vergleich zu Klasse 1A an mehreren Stellen aufwiesen: ZNS (7,4% vs. 0,9%), Lunge (7,4% vs. 1,2%), Leber (4,5% vs. 0,6%) und Knochen (3,0% vs. 0,8%).
Zusätzlich ergab die Forschung zu DecisionDx-UM beim uvealen Melanom, dass von 79 Patienten 72% als Niedrigrisiko (Klasse 1) und 28% als Hochrisiko für Metastasen eingestuft wurden. Die Studie identifizierte signifikante Proteinunterschiede in Proben des Kammerwassers zwischen den Risikoklassen (N=386, p<0,0001), was potenziell eine frühere Erkennung und Intervention bei uvealen Melanozytärtumoren ermöglicht.
- DecisionDx-Melanoma demonstrated significant accuracy in identifying high-risk patients across multiple metastasis sites
- DecisionDx-UM showed strong classification capability with 72% low-risk and 28% high-risk patient identification
- Development of new minimally invasive liquid biopsy approach for early detection
- Class 2B patients showed persistently elevated metastasis risk several years after diagnosis
- Up to 50% of uveal melanoma patients develop metastatic disease
Insights
DecisionDx-Melanoma shows significant ability to identify early-stage melanoma patients at high risk for distant metastasis, supporting more personalized treatment approaches.
The new data from Castle Biosciences demonstrates clinically meaningful risk stratification capabilities of their DecisionDx-Melanoma test in early-stage melanoma patients. The study of 1,661 AJCC stage I-II patients reveals that the 31-gene expression profile effectively identifies those at elevated risk for distant metastasis to critical organs. Patients with Class 2B (highest risk) results showed substantially higher distant metastasis rates compared to Class 1A (lowest risk):
Particularly noteworthy is that high-risk patients exhibited significantly lower five-year distant metastasis-free survival, with elevated risk persisting for several years post-diagnosis. This temporal risk persistence is clinically significant as it suggests the need for extended surveillance protocols for high-risk patients.
The findings suggest integrating DecisionDx-Melanoma with traditional AJCC staging could improve risk-appropriate surveillance strategies. This combined approach may enable earlier metastasis detection in high-risk patients while potentially reducing unnecessary interventions in those at lower risk.
Additionally, the early research on aqueous humor (AH) protein biomarkers addresses a critical unmet need in uveal melanoma management. The development of a minimally invasive liquid biopsy could potentially overcome the clinical challenges of monitoring small uveal melanocytic tumors where conventional biopsies are impractical. The identification of 386 proteins with significant differences between risk classes provides a promising foundation for future diagnostic development in this rare but aggressive ocular cancer.
Castle Biosciences strengthens clinical utility evidence for DecisionDx-Melanoma while advancing early-stage research for potential uveal melanoma liquid biopsy technology.
The new research presented at AACR provides incremental validation for Castle Biosciences' flagship DecisionDx-Melanoma test, building on previous findings from ASCO 2024. The data strengthens the test's clinical utility proposition by demonstrating its ability to identify specific distant metastasis risks across multiple organs, which could potentially influence surveillance protocols and treatment planning for early-stage melanoma patients.
From a market perspective, these findings enhance DecisionDx-Melanoma's value proposition by providing more granular risk information that can guide clinical decision-making. The robust statistical significance in the study of 1,661 patients lends credibility to these findings, potentially supporting broader clinical adoption and utilization.
The uveal melanoma research represents earlier-stage pipeline development but addresses an important clinical challenge in monitoring small uveal melanocytic tumors. The development of a liquid biopsy approach via aqueous humor protein biomarkers shows forward-looking innovation within Castle's R&D pipeline. If successfully developed and validated, such a test could complement Castle's existing DecisionDx-UM test and potentially expand their addressable market within this rare but high-mortality cancer segment.
While this research doesn't represent an entirely new product launch or immediate revenue catalyst, it demonstrates Castle's commitment to expanding the clinical evidence supporting their test portfolio. In the precision diagnostics market, robust clinical validation is a key driver of physician adoption, payer coverage, and potential guideline inclusion - all factors that support sustainable long-term market position. The findings point to incremental enhancement of Castle's existing melanoma testing franchise rather than transformative new product development.
FRIENDSWOOD, Texas, April 25, 2025 (GLOBE NEWSWIRE) -- Castle Biosciences, Inc. (Nasdaq: CSTL), a company improving health through innovative tests that guide patient care, will share new research intended to improve the care of patients with cutaneous and uveal melanoma (CM and UM, respectively) via poster presentations at the American Association for Cancer Research® (AACR) Annual Meeting 2025, being held April 25-30 in Chicago.
"At Castle Biosciences, our commitment to advancing care for melanoma patients helps drive our continuous innovation," said Rebecca Critchley-Thorne, Ph.D., vice president, research and development, of Castle Biosciences. "The new data being presented at AACR underscores this commitment and further advances our mission to improve health through innovative tests that can help guide personalized treatment strategies designed to enhance patient outcomes.”
Castle will present the following posters at AACR (all times Central Time). The corresponding abstracts are available on AACR’s website using the inline links below.
DecisionDx-Melanoma
- Abstract 3344: The 31-gene expression profile identifies patients at risk of developing early distant metastases and can guide risk-appropriate surveillance strategies
- Lead Author and Presenter: Merve Hasanov, M.D., oncologist and director of the division of medical oncology at The Ohio State University Comprehensive Cancer Center, Columbus, Ohio
- Session Category: Clinical Research
- Session Title: Prognostic Biomarkers 2
- Location: Poster Section 32
- Poster Board Number: 14
- Date & Time: April 28, 2-5 p.m.
- Summary: Building on findings presented at ASCO 2024, this study demonstrates that DecisionDx-Melanoma can identify early-stage CM patients (American Joint Committee on Cancer (AJCC) stage I-II, n=1,661) at higher risk of distant metastasis (DM) not only to the central nervous system (CNS), but also to the lung, liver and bone. Patients with Class 2B (highest risk) results showed significantly higher DM rates compared to Class 1A (lowest risk) patients across all sites: CNS (
7.4% vs.0.9% , p<0.001), lung (7.4% vs.1.2% , p<0.001), liver (4.5% vs.0.6% , p<0.001) and bone (3.0% vs.0.8% , p<0.05). Notably, Class 2B patients had significantly lower five-year DM-free survival and elevated metastasis risk persisted several years after diagnosis, particularly to CNS and lung. These results support combining DecisionDx-Melanoma with AJCC staging to potentially identify high-risk patients for tailored surveillance and treatment strategies, which may enable earlier metastasis detection and potentially improve survival outcomes.
DecisionDx-UM
- Abstract LB262: Development of a clinically feasible aqueous proteomic signature to assess the malignant potential of small uveal melanocytic tumors
- Session Title: Late-Breaking Research: Clinical Research 2 / Endocrinology
- Location: Poster Section 51
- Poster Board Number: 11
- Date & Time: April 29, 9 a.m.-12 p.m.
- Summary: UM, though rare, is the most common eye cancer, with up to
50% of patients developing metastatic disease. While tumor biopsy-based molecular testing is widely utilized to identify high-risk biology, repeated intraocular tumor biopsies are not feasible for monitoring small uveal melanocytic tumors of indeterminate malignant potential (UMTIMP). This study seeks to address this unmet clinical need by evaluating aqueous humor (AH) protein biomarkers—obtainable through a minimally invasive office-based liquid biopsy from the anterior chamber of the eye—to help identify high-risk lesions early to help inform the decision to biopsy. Among 79 UM patients assessed with the DecisionDx-UM test (the current standard of care for evaluating metastatic risk in UM),72% (57/79) were classified as low risk (Class 1) and28% (22/79) as high risk for developing metastasis. The study identified proteins in the AH with significant differences between risk classes (N=386, p<0.0001) for the development of several risk prediction models. The proteins from the highest-performing models may be further evaluated for their ability to detect high-risk UMTIMPs with a goal of enabling more timely clinical decisions, determining the need for further prognostic testing (DecisionDx-UM, -PRAME, -UMSeq), and potentially allowing for earlier therapeutic intervention to improve patient outcomes.
About DecisionDx-Melanoma
DecisionDx-Melanoma is a 31-gene expression profile (31-GEP) risk stratification test. It is designed to inform two clinical questions in the management of cutaneous melanoma: a patient’s individual risk of sentinel lymph node (SLN) positivity and a patient's personal risk of melanoma recurrence and/or metastasis. By integrating tumor biology with clinical and pathologic factors using a validated proprietary algorithm, DecisionDx-Melanoma is designed to provide a comprehensive and clinically actionable result to guide risk-aligned patient care. DecisionDx-Melanoma has been shown to be associated with improved patient survival and has been studied in more than 10,000 patient samples. DecisionDx-Melanoma’s clinical value is supported by more than 50 peer-reviewed and published studies, providing confidence in disease management plans that incorporate the test’s results. Through Dec. 31, 2024, DecisionDx-Melanoma has been ordered more than 191,000 times for patients diagnosed with cutaneous melanoma. Learn more at www.CastleBiosciences.com.
About DecisionDx-UM
DecisionDx-UM is Castle Biosciences’ 15-gene expression profile (15-GEP) test that uses an individual patient’s tumor biology to predict individual risk of metastasis in patients with uveal melanoma (UM). DecisionDx-UM is the standard of care in the management of newly diagnosed UM in the majority of ocular oncology practices in the United States. Since 2009, the American Joint Committee on Cancer (AJCC; v7 and v8) Staging Manual for UM has specifically identified the GEP test as a prognostic factor that is recommended for collection as a part of clinical care. Further, the National Comprehensive Cancer Network (NCCN) guidelines for UM include the DecisionDx-UM test result as a prognostic method for determining risk of metastasis and recommended differential surveillance regimens based on a Class 1A, 1B and 2 result. DecisionDx-UM is currently the only prognostic test for UM that has been validated in prospective, multi-center studies, and it has been shown to be a superior predictor of metastasis compared to other prognostic factors, such as chromosome 3 status, mutational status, AJCC stage and cell type. It is estimated that nearly 8 in 10 patients diagnosed with UM in the United States receive the DecisionDx-UM test as part of their diagnostic workup. Learn more at www.CastleBiosciences.com.
About Castle Biosciences
Castle Biosciences (Nasdaq: CSTL) is a leading diagnostics company improving health through innovative tests that guide patient care. The Company aims to transform disease management by keeping people first: patients, clinicians, employees and investors.
Castle’s current portfolio consists of tests for skin cancers, Barrett’s esophagus, mental health conditions and uveal melanoma. Additionally, the Company has active research and development programs for tests in other diseases with high clinical need, including its test in development to help guide systemic therapy selection for patients with moderate-to-severe atopic dermatitis seeking biologic treatment. To learn more, please visit www.CastleBiosciences.com and connect with us on LinkedIn, Facebook, X and Instagram.
DecisionDx-Melanoma, DecisionDx-CMSeq, i31-SLNB, i31-ROR, DecisionDx-SCC, MyPath Melanoma, DiffDx-Melanoma, TissueCypher, IDgenetix, DecisionDx-UM, DecisionDx-PRAME and DecisionDx-UMSeq are 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 “safe harbor” created by those sections. These forward-looking statements include, but are not limited to, statements concerning: the ability of DecisionDx-Melanoma to identify early-stage melanoma patients at high risk of DM to enable risk-appropriate surveillance and treatment; Castle’s ability to continuously innovate; the ability of new data to further advance Castle’s mission to improve health through innovative tests that can help guide personalized treatment strategies designed to enhance patient outcomes; the ability of Castle’s tests to enable more personalized treatment and improve patient outcomes; the ability of DecisionDx-Melanoma, combined with AJCC staging, to identify high-risk patients and enable earlier metastasis detection and improve survival outcomes; and the ability of the DecisionDx-UM test to detect high risk UMTIMP’s and to allow earlier therapeutic intervention to improve patient outcomes. The words “believe,” “can” and similar expressions are intended to identify forward-looking statements, although not all forward-looking statements contain these 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 that we make. These forward-looking statements involve risks and uncertainties that could cause our actual results to differ materially from those in the forward-looking statements, including, without limitation: subsequent study or trial results and findings may contradict earlier study or trial results and findings or may not support the results obtained in these studies, including with respect to the discussion of our tests in this press release; actual application of our tests may not provide the aforementioned benefits to patients; and the risks set forth under the heading “Risk Factors” in our Annual Report on Form 10-K for the year ended December 31, 2024, and in our other filings with the SEC. The forward-looking statements are applicable only as of the date on which they are made, and we do not assume any obligation to update any forward-looking statements, except as may be required by law.
Investor Contact:
Camilla Zuckero
czuckero@castlebiosciences.com
Media Contact:
Allison Marshall
amarshall@castlebiosciences.com
FAQ
What are the key findings of CSTL's DecisionDx-Melanoma study presented at AACR 2025?
How effective is CSTL's DecisionDx-UM test in identifying uveal melanoma risk?
What new biomarker approach is CSTL developing for uveal melanoma detection?
How can DecisionDx-Melanoma improve patient treatment strategies?
