Castle Biosciences, Inc. announced new discovery data from an ongoing study exploring the potential for developing a complementary, minimally invasive test to evaluate small, suspicious lesions of uncertain malignant potential in patients' eyes. The current clinical standard of care to determine which patients to treat involves a "watch and wait" approach that consists of monitoring lesions for growth or appearance of high-risk features that would indicate transformation into a malignant melanoma. Castle's ongoing exploratory study is investigating the potential for developing a test that would complement DecisionDx-UM and provide a minimally invasive solution to identify lesions with aggressive biology earlier, enabling more timely treatment with the goal of improving uveal melanoma patient outcomes.

DecisionDx-UM is Castle Biosciences' 15-gene expression profile (GEP) test that uses an individual patient's tumor biology to predict individual risk of metastasis in patients with uveal melanoma. 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 uveal melanoma 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 the only prognostic test for uveal melanoma 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.