Dec 11, 2025 By Kristin Emery 4 min read

Study results show a new technique that analyzes genomic information from a type of skin cancer tumor could help melanoma patients avoid additional surgery on their lymph nodes. The test was developed by the Mayo Clinic and SkylineDx and can help determine whether patients with melanoma are at a high or low risk for additional cancer in their lymph nodes.

The study showed nearly 93% of patients classified as low risk by the test had no cancer in their lymph nodes while roughly 25% of patients in the high risk group did. The clinical trial used data from more than 1,700 patients with early or middle stage melanoma across the country between 2021 and 2024.

Melanoma is the deadliest form of skin cancer, though it can often be successfully treated in early stages. However, the risk of recurrence increases if it spreads to the lymph nodes. That’s why this test could prove to be a game changer in determining treatment.

“A sentinel lymph node biopsy, which samples the first lymph node where melanoma would likely spread, remains the best way to detect whether the cancer has reached the lymph nodes,” says Dr. Deanna Huffman, Medical Oncology Lead with the AHN Skin Cancer Center of Excellence. “This information helps oncologists like me decide whether a patient might benefit from additional treatments such as immunotherapy.” Current guidelines recommend avoiding this second biopsy in patients who are unlikely to have affected lymph nodes, but Huffman cautions that skipping it also risks missing melanoma that may have already spread.

How does it work?

The test in the trial measured activity in eight genes inside melanoma tumors collected during an initial biopsy, then factored in the patient’s age and tumor thickness to generate the chance that cancer had reached the lymph nodes. A low risk could help prevent the need for a lymph node biopsy, which usually requires a second incision and can have side effects.

“Tests like this one may eventually help us better identify who can safely avoid the biopsy,” says Huffman. She sees the results as positive progress and the test as a useful tool but cautions it’s not right for every situation.

“While this particular test could not reliably single out those at the very lowest risk, it may be useful for patients who fall into a gray area, such as those who are less likely to have spread but may also face higher risks from surgery due to other health issues,” Huffman says. “It adds information for risk assessment but isn’t yet ready to replace the sentinel lymph node biopsy as a decision-making tool.”

She sees this test as one tool that can provide additional data and help to guide a conversation between patients and surgeons about the risks and benefits of a procedure.

“They’re not designed to give a definite ‘yes or no’, but rather to help personalize decision-making.”

Is genomic testing the future?

“We’re seeing rapid growth in the use of less invasive testing, including genetic profiling, to guide care,” Huffman said. “These tests are still being integrated into existing guidelines, but the data we’re gathering will only make them more accurate over time.”

Less invasive testing can reduce costs, shorten wait times, and spare patients from stressful or painful procedures. As technology improves, she says we may also see faster results and, most importantly, fewer unnecessary treatments or surgeries for patients who don’t need them. “These tests can offer benefits in cost, time, and the potential to avoid unnecessary procedures or treatments,” Huffman says. “They also help patients make more informed decisions, for example, whether to proceed with a sentinel lymph node biopsy based on their individual level of risk.”

Genetic testing in cancer can be done in several ways, often using tissue from a biopsy, and in some cases from a blood sample. Gene expression profiling (GEP) tests, like the one in this study, analyze tumor tissue to see how active certain genes are. The pattern, or “gene profile,” can help predict specific tumor behaviors.

“In this study, researchers looked at a profile of eight genes linked to whether melanoma is likely to have spread to a sentinel lymph node,” Huffman said. “Similar tests are already used in other cancers. For instance, in breast cancer, a GEP test helps estimate the likelihood of breast cancer recurrence and guides decisions about whether chemotherapy would be beneficial.” Looking ahead, she thinks we’ll see these types of tests used more widely across many cancers.

“They could help tailor treatment to each patient’s unique tumor biology, though we still have more work to do before that becomes routine.”