Experts highlight lack of reliable biomarkers for melanoma immunotherapy response

Dr. Mario Sznol, a professor of clinical medical oncology at the University of Miami, discussed the ongoing difficulty of predicting which patients with metastatic melanoma will benefit from immune checkpoint inhibitors.

He noted that commonly used biomarkers such as tumor mutational burden and PD‑L1 expression have not shown consistent clinical utility in melanoma, making it hard to select patients for these therapies.

While several experimental markers-including microbiome composition, HLA class I expression, and aspects of tumor microenvironment metabolism-show promise, they remain difficult to combine into a clear, actionable testing strategy.

Sznol emphasized that research continues to explore these avenues, but a reliable, clinically useful biomarker panel is not yet available.