Ultrasensitive detection of BRAF mutations in circulating tumor DNA of non-metastatic melanoma

ESMO Open. 2022 Feb;7(1):100357. doi: 10.1016/j.esmoop.2021.100357. Epub 2021 Dec 20.

Abstract

Background: Implementation of adjuvant therapies in non-metastatic melanoma improved treatment outcomes in some patients; however, adjuvant therapy can be associated with significant cost and risk of toxicity. Therefore, there is an unmet need to better identify patients at high risk of recurrence.

Patients and methods: We carried out an ultrasensitive droplet digital PCR (ddPCR)-based detection of BRAFV600E-mutated circulating tumor DNA (ctDNA) from blood samples prospectively collected before surgery, 1 hour after surgery, and then serially during follow-up.

Results: In 80 patients (stages ≤III), BRAFV600E mutations were detected in 47.2% of tissue, in 37.7% of ctDNA samples collected before surgery, and in 25.9% of ctDNA samples collected 1 hour after surgery. Patients with detected ctDNA in blood collected 1 hour after surgery compared to patients without detected ctDNA had higher likelihood of melanoma recurrence (P < 0.001) and shorter median disease-free survival (P = 0.001) and overall survival (P = 0.003).

Conclusions: Ultrasensitive ddPCR can detect ctDNA in pre- and post-surgical blood samples from patients with resectable melanoma. Detection of ctDNA in post-surgical samples is associated with inferior treatment outcomes.

Keywords: circulating tumor DNA; liquid biopsy; melanoma.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Circulating Tumor DNA* / genetics
  • Humans
  • Melanoma* / genetics
  • Mutation*
  • Polymerase Chain Reaction
  • Proto-Oncogene Proteins B-raf* / genetics

Substances

  • Circulating Tumor DNA
  • BRAF protein, human
  • Proto-Oncogene Proteins B-raf