DecisionDx^®-Melanoma Overview

Predicting Individual Risk of Recurrence or Metastasis

DecisionDx-Melanoma was designed to address the need for a more accurate predictor of metastatic risk in patients diagnosed with cutaneous (skin) melanoma.

Traditional Approaches May Have Limitations

Prior to the introduction of DecisionDx-Melanoma, nearly all treatment plan decisions made around the time of diagnosis relied solely upon traditional clinical and pathologic prognostic factors, including whether to perform the invasive sentinel lymph node biopsy (SLNB) surgical procedure to see whether cancer cells were found in lymph nodes.

However, the traditional clinical and pathology factors that drive clinician management decisions and SLNB recommendations have limitations. Unfortunately, despite being classified as low risk, two out of three patients who develop metastatic disease and die from their primary melanoma tumor were initially classified as Stage I or II, many of whom received an SLN-negative biopsy result following SLNB surgery. In fact, approximately 88% of patients who undergo the SLNB surgery are found to have an SLN-negative biopsy result, meaning they remain categorized as lower risk (Stage I or II). 

We saw an opportunity to improve patient care by adding personalized genomic information to address this situation.  We believed that by using the latest molecular diagnostic techniques, we could better understand the biological behavior of a patient’s tumor and enable improvement over traditional clinical and pathologic factors.

Designed to Identify Risk of Recurrence or Metastasis Including the Likelihood of Sentinel Lymph Node Positivity

DecisionDx-Melanoma, our gene expression profile (GEP) test for melanoma prognosis was designed to identify the risk of recurrence or metastasis in patients with Stage I, II, and III melanoma based on the biologic profile of 31 genes within their tumor tissue.  DecisionDx-Melanoma has been included in 30 peer-reviewed publications and has been studied in more than 5,700 patient samples. The test has been validated in four archival risk of recurrence studies of 901 patients and six prospective risks of recurrence studies including more than 1,600 patients. Prediction of the likelihood of sentinel lymph node positivity has also been validated in two prospective multicenter studies that included more than 3,000 patients. Impact on patient management plans for one of every two patients tested has been demonstrated in four multicenter and single-center studies including more than 560 patients. The consistent performance and accuracy demonstrated in these studies provide confidence in disease management plans that incorporate DecisionDx-Melanoma test results. 

Today, more than 7,700 healthcare professionals have trusted and incorporated DecisionDx-Melanoma into their practice.  The test results are used to guide two treatment plan decisions that are made around the time of diagnosis:

1. Guide management decisions such as surveillance, follow-up frequency and referrals in patients with tumors ≥0.3 mm thick

2. Identify the likelihood of sentinel lymph node positivity using the independently validated i31-GEP algorithm that combines a patient’s clinical and pathologic factors with the DecisionDx-Melanoma test score. This integrated test result is designed to provide a more precise and personalized SLN positivity risk prediction to better identify patients with a low risk of SLN positivity who could potentially forgo the procedure and those patients at high risk of SLN positivity who should consider and be offered a SNLB. 

DecisionDx-Melanoma is performed in Castle Biosciences’ CAP accredited, CLIA certified laboratory using formalin-fixed, paraffin embedded (FFPE) primary tumor tissue from either a biopsy or excision.