Benzinga | Apr 14, 2021 07:15AM EDT

Castle Biosciences Highlights Publication Of DecisionDx-Melanoma Data In American Journal of Surgery

Castle Biosciences, Inc. (NASDAQ:CSTL), a skin cancer diagnostics company providing personalized genomic information to improve cancer treatment decisions, today announced data from an independent, prospective study published in the American Journal of Surgery demonstrating DecisionDx(r)-Melanoma's utility for prediction of outcomes in patients with cutaneous melanoma. DecisionDx-Melanoma is Castle's gene expression profile test that uses an individual patient's tumor biology to predict risk of cutaneous melanoma metastasis or recurrence, as well as sentinel lymph node positivity, independent of traditional staging factors.

The publication, titled "Utility of a 31-gene expression profile for predicting outcomes in patients with primary cutaneous melanoma referred for sentinel node biopsy," describes a study comparing tumor features, sentinel node biopsy (SLNB) results, and patient outcomes from a prospective database of 383 patients with cutaneous melanoma who both underwent SLNB and had their primary tumor assayed with DecisionDx-Melanoma. Groups were compared by univariate and multivariate analyses, and relapse-free and distant metastasis-free survival (RFS, DMFS) were estimated by Kaplan-Meier method.

The study's results demonstrated that a Class 2 (high-risk) DecisionDx-Melanoma result was significantly associated with higher rates of SLNB positivity compared to Class 1 (low risk). With respect to risk prognoses, patients who received a Class 2B DecisionDx-Melanoma result and were SLNB-positive experienced the highest recurrence rates (38%), compared to only a 2% recurrence rate for patients who were Class 1A and SLNB-negative. DecisionDx-Melanoma Class 2 results were significantly associated with poorer RFS and DMFS rates compared to Class 1 results, both in the entire cohort of 383 cases and in patients staged as "low risk" (IA-IIA) according to American Joint Committee on Cancer (AJCC) staging criteria.

"We sought to study the utility of this 31 gene expression profile (31-GEP) test in the largest, independent, prospective study to date," said corresponding author John T. Vetto, M.D., FACS, Professor of Surgery, Division of Surgical Oncology, Oregon Health & Science University, Portland. "Current staging parameters in melanoma are invaluable but also imperfect. We were encouraged to find that, like AJCC stage, the 31-GEP results were independently associated with patient outcomes, including recurrence and distant metastasis, and that the 31-GEP results added prognostic information when incorporated with existing features to evaluate patient risk."