Research Discovery: A Blood Test May Help Track Melanoma and Guide Care

Researchers explored how circulating tumor DNA, or ctDNA, might be used in melanoma care. ctDNA consists of tiny pieces of genetic material released by cancer cells into the bloodstream.

A blood test—sometimes called a liquid biopsy—can look for this tumor DNA. It may provide information about whether melanoma is still present, has returned, or is responding to treatment.

This study surveyed 116 melanoma experts from 27 countries. It gathered their opinions about when ctDNA testing may be most helpful and what must happen before it can become a routine part of care. The study assessed expert perspectives; it did not test whether ctDNA improves patient outcomes.

How It Works

The experts answered questions about the value of ctDNA testing at different stages of melanoma. They also reviewed five examples based on real patient situations, including:

• Detecting very small amounts of cancer remaining after treatment
• Monitoring for melanoma recurrence
• Clarifying uncertain imaging results
• Making urgent treatment decisions when tumor tissue testing is delayed or unavailable
• Monitoring treatment response and deciding when treatment may need to change

Experts were also asked about practical issues such as testing costs, how quickly results should be available, and barriers to using ctDNA in everyday care.

Key Findings

Experts saw the greatest potential for ctDNA testing in advanced melanoma, detecting small amounts of cancer remaining after treatment, and identifying melanoma that has returned.

Most respondents reported that:

• 80% believed ctDNA results generally reflect how a tumor is responding on clinical exams or imaging.
• 82% supported adding ctDNA testing to routine follow-up care.
• Experts often considered ctDNA more useful than the traditional blood markers S100 and LDH for detecting recurrence or disease progression.
• In an urgent situation involving advanced melanoma, 83% would use ctDNA results to begin targeted treatment while waiting for tumor tissue results. This increased to 94% if tissue testing was not possible.
• ctDNA testing appeared less useful for people with early-stage melanoma, when very small amounts of tumor DNA may be difficult to detect.
• For melanoma involving the brain or central nervous system, most experts did not consider blood-based ctDNA testing helpful. However, 66% thought testing fluid surrounding the brain and spinal cord could provide useful information.

Experts preferred focused tests that could provide results quickly and at a reasonable cost. However, they identified several major barriers to routine use:

• 85% said larger forward-looking clinical studies are needed.
• 83% cited the lack of standardized clinical guidelines.
• 82% identified uncertainty about insurance coverage and reimbursement.

Because the findings reflect expert opinions—primarily from academic melanoma centers—they do not establish that ctDNA testing should replace current diagnostic or monitoring methods.

Community Impact

ctDNA testing could eventually offer people with melanoma a less invasive way to monitor their cancer through a blood draw. It may help detect recurrence earlier, provide more information when scans are unclear, and support faster treatment decisions when obtaining tumor tissue is difficult.

For now, ctDNA should be viewed as a possible addition to—not a replacement for—imaging, tissue testing, and other parts of melanoma care. More research is needed to determine when testing should be performed, how results should guide treatment, whether its use improves patient outcomes, and how access and insurance coverage can be made equitable.