Uveal Melanoma

DecisionDx-UM Overview

Highly accurate prognostic tool is standard of care in eye cancer

Uveal melanoma, commonly known as ocular or choroidal melanoma, is a rare cancer of the eye. While the primary tumor is highly treatable, about half of patients will go on to develop metastasis —typically to the liver. While traditional staging methods such as tumor size and location still play a role in assessing metastatic risk, they are rarely used to individualize patient management plans.

The DecisionDx®-UM test was originally developed by ocular oncologist Dr. J. William Harbour while at Washington University (now at Bascom Palmer Eye Institute). The test measures the activity, or gene expression, of a set of 15 genes within an ocular melanoma tumor to identify the likelihood of metastasis within five years. Castle Biosciences exclusively licensed the technology and validated the test for clinical use in 2009. Since its introduction in 2009, the gene expression profile (GEP) test has become an important prognostic tool for uveal melanoma, and is now used as standard of care by over 95% of ocular oncologists in the U.S.

Clinical Utility

DecisionDx-UM enables a doctor to determine the intensity of a patient’s surveillance and management plan based on an accurate assessment of their individual risk. A recent study published in Clinical Ophthalmology (Aaberg et al, 2014), which involved doctor surveys and medical chart review of Medicare treated patients, showed that molecular testing such as the DecisionDx-UM test has a significant impact on the management of uveal melanoma. Not only are most ophthalmologists treating uveal melanoma using molecular testing to enable a risk appropriate reduction in the intensity of a patient’s surveillance and management plan based upon a low risk test result, but they are maintaining a high frequency disease monitoring plan and recommend clinical trials for those patients whose test results showed they were at high risk of metastasis.

These data were corroborated in a prospective, multi-center study (Plasseraud et al, 2016) in which physicians independently prescribed low-risk patients a lower intensity surveillance plan that matched their DecisionDx-UM risk profile while maintaining the more intense surveillance regimens for high-risk patients as determined by the DecisionDx-UM test.

Scientific Validation

To date, DecisionDx-UM is the only prognostic test for uveal melanoma that has been clinically validated for accuracy in multiple prospective and retrospective multi-center and single-center studies. According to a 446-patient study conducted by the Collaborative Ocular Oncology Group (COOG), the DecisionDx-UM test is clinically and statistically superior to all other prognostic factors in predicting metastatic risk—including clinical and pathologic factors—as well as chromosome 3 testing (Onken et al., 2012). These results are comparable to additional single-center and multi-center prospective and retrospective studies (Onken et al., 2010; Chappell et al., 2012; Correa & Augsburger et al., 2014; Plasseraud et al, 2016 Demirci et al, 2015; ).

Optional PRAME Testing

Castle Biosciences is now offering DecisionDx®-PRAME gene expression profile testing to assess expression of the PRAME (preferentially expressed antigen in melanoma) gene. The test is available as an option for patients who are undergoing the DecisionDx-UM test. Elevated expression of PRAME has been associated with an increased risk of metastasis in patients with uveal melanoma (Field et al., 2016; Field et al., 2016). When used in conjunction with results from the DecisionDx-UM test, PRAME expression status may add further precision to the predicted risk of metastasis and help guide physicians and patients to the most appropriate follow-up care regimens.

Additional studies of the relationship between PRAME and uveal melanoma patient tumors are underway, including a prospective, multi-center study.

More information about the DecisionDx-UM and DecisionDx-PRAME tests, along with information on uveal melanoma can be found at www.MyUvealMelanoma.com.