DecisionDx-Melanoma is a gene expression profile risk stratification test designed to inform a patient’s individual risk of SLN positivity and a patient's personal risk of melanoma recurrence and/or metastasis. 

The use of Castle Biosciences, Inc. DecisionDx-Melanoma test results to guide radiological surveillance may lead to improved patient outcomes, according to a new study in Archives of Dermatological Research.

The new study, conducted at three National Cancer Institute-designated cancer centers, included patients with Stage I or II cutaneous melanoma who had a negative sentinel lymph node biopsy. The experimental group was comprised of patients who had received high-risk DecisionDx-Melanoma test results and thus received routine imaging every six to twelve months. Patients in the control group did not receive DecisionDx-Melanoma testing and had imaging studies driven only by clinical symptoms or physical exam findings.

Key findings of the study include:

• Patients in the experimental group who received DecisionDx-Melanoma testing and surveillance imaging had melanoma recurrences detected approximately ten months earlier than patients in the control group.
• The average tumor burden detected at patients’ melanoma recurrence was significantly lower in the experimental group compared to the control group. (Note: recent studies cited in the paper suggest a survival benefit when metastatic melanoma is treated at a lower tumor burden.
• Of the patients with a recurrence, 82% in the experimental group and 71% in the control group started immunotherapy.
• At patients’ last follow up, 76% of the patients with melanoma recurrence in the experimental group were alive (average follow-up time=45.6 months), compared to 50% of recurrent melanoma patients in the control group (average follow-up time=63.3 months).

Overall, the study found that using DecisionDx-Melanoma to risk-stratify patients to guide care resulted in earlier detection of melanoma recurrence while the tumor burden was lower, which could lead to improved patient outcomes.

We believe this study is significant in that it provides a direct chain of evidence between the use of DecisionDx-Melanoma to guide treatment plan decisions, which could result in improved survival compared to patients from the same institution who did not have their treatment plans informed by our test,” says Derek Maetzold, president and chief executive officer of Castle Biosciences, in a news release.