Castle Biosciences Inc. has announced the publication of study results that assess current clinical practices for uveal melanoma (UM) and demonstrate the impact of molecular prognostic testing on patient management. The paper, "Current clinical practice: differential management of uveal melanoma in the era of molecular tumor analyses," was published in the peer-reviewed journal Clinical Ophthalmology.

The publication presents results from three studies: a survey of 109 ophthalmologists specializing in the treatment of uveal melanoma conducted in 2012; a follow-up survey of 72 physicians in 2014; and a retrospective medical record review of 195 consecutively tested Medicare patients with UM. Consistent across all three studies, a majority of ophthalmologists treating UM use molecular diagnostic tests to help design risk-appropriate treatment follow-up plans for their patients. Castle Biosciences' prognostic test for uveal melanoma, DecisionDx-UM, is a molecular diagnostic test that measures the gene expression profile (GEP) of an individual's tumor and classifies the likelihood of metastasis as low risk (Class 1) or high risk (Class 2).

"The ability to better assess risk represents an important shift in the management of uveal melanoma patients," commented study author Thomas M. Aaberg, Jr., Michigan State University Medical School and Retina Specialists of Michigan. "Since less than 5% of patients have detectable metastatic disease at the time their primary tumor is diagnosed, there is great need for a more accurate tool to assess the risk of metastasis. These results suggest that physicians have widely adopted the new prognostic tools, and have incorporated the results to devise the most appropriate follow-up care plans for patients. Ultimately, we hope to use these tools to design and appropriately enroll patients into clinical trials aimed at prophylactically treating uveal melanoma patients at high risk for metastatic disease."

Study Details

Based on the results from the Medicare medical records review, 58% of patients undergoing the DecisionDx-UM test had a low risk (GEP Class 1) result and 42% were high risk (GEP Class 2). In cases where documented reference to follow-up systemic surveillance was made, all of the low risk patients underwent a low-intensity plan including liver function tests with or without abdominal ultrasound at a frequency of one or two times per year. In contrast, 100% of the high risk patients were followed with high intensity surveillance, primarily defined as liver function tests and abdominal ultrasound, CT, and/or positron emission tomography (PET) at a frequency of 2 to 4 times per year (P<0.0001 versus Class 1 surveillance).

Ophthalmologist Survey Results

  • 74% of ophthalmologists who participated in the 2012 survey used the information obtained from cytogenetic or GEP analyses to adjust the frequency of metastatic disease surveillance for their patients;
  • For patients at higher risk of metastasis, 15% of doctors offered prophylactic therapy and 23% offered participation in clinical trial of investigational therapy.
  • 79% of respondents who participated in the 2014 survey used the information from cytogenetic or GEP analyses to change their clinical practice, such as adjusting the frequency of metastatic disease surveillance, referral to medical oncology for follow-up, and/or counseling/referral regarding adjuvant treatment or clinical trials.

"These data support the conclusion that molecular analyses, including GEP testing (DecisionDx-UM), have been widely accepted and adopted to support more informed uveal melanoma management decisions. In addition to the impact on patient management, the results from these tests are now used as entry criteria for clinical trials involving adjuvant therapies," said Derek Maetzold, President and CEO of Castle Biosciences.