Early Circulating Tumour DNA Variations Predict Tumour Response in Melanoma Patients Treated with Immunotherapy

Area of Science:

• Oncology
• Immunotherapy
• Molecular Diagnostics

Background:

• Immune checkpoint inhibitors are approved for metastatic melanoma but lack universal efficacy.
• Some patients experience severe immune-related adverse events.
• Early identification of non-responders is crucial for optimizing clinical management.

Purpose of the Study:

• To evaluate the utility of circulating tumor DNA (ctDNA) monitoring for predicting response to immunotherapy in metastatic melanoma.
• To correlate ctDNA dynamics with treatment outcomes and adverse events.

Main Methods:

• Digital droplet PCR was employed to quantify BRAF and NRAS mutations in plasma ctDNA.
• ctDNA levels were monitored in patients with metastatic melanoma undergoing immunotherapy.

Main Results:

• ctDNA variations correlated significantly with tumor response (p=0.034).
• Increased ctDNA levels accurately predicted tumor progression (100% specificity).
• Early ctDNA changes were linked to clinical decisions (p=0.0046) and shorter progression-free survival.

Conclusions:

• Early ctDNA monitoring can help clinicians identify non-responder patients during immunotherapy.
• This approach facilitates rapid therapeutic strategy adaptation.
• It potentially reduces patient exposure to ineffective and costly treatments.