Four-month course of adjuvant dabrafenib in patients with surgically resected stage IIIC melanoma characterized by a BRAFV600E/K mutation.

Abstract

BACKGROUND:

We tested the hypothesis that a 4-month course of adjuvant dabrafenib in stage IIIC BRAF-mutated melanoma would improve 2 year RFS from 24% to 51%, and that tumor-derived cell free DNA (cfDNA) in plasma would correlate with and predict recurrence.

METHODS:

Patients with stage IIIC BRAF V600E/K mutated melanoma who were free of disease after surgical resection received 4 months of adjuvant dabrafenib. Patients were evaluated with imaging at baseline, at the end of cycles 2, 4, 6, then every 3 months until disease relapse or 2 years, whichever came first. Serial blood samples were collected for evaluation of cfDNA at the same time.

RESULTS:

21/23 patients enrolled were evaluable; 2 patients withdrew consent during the first week of treatment. The 2 year RFS was 28.6% (95% CI 12-48%). The estimated overall survival at 2 years was 78% (95% CI 51-91%). cfDNA detection had a 53% sensitivity in relapsing patients but cfDNA detection did not provide lead-time advantage over CT scanning.

CONCLUSION:

A 4-month course of adjuvant dabrafenib did not result in a detectable improvement in 2-year RFS. cfDNA was less sensitive than standard CT imaging and did not provide a lead-time advantage in detecting relapse.

• Authors: Parisa Momtaz, James J Harding, Charlotte Ariyan, Daniel G Coit, Taha Merghoub, Billel Gasmi, Daoqi You, Agnes Viale, Katherine S Panageas, Aliaksandra Samoila, Michael A Postow, Jedd D Wolchok, Paul B Chapman
• Journal: Oncotarget (Oncotarget) Vol. 8 Issue 62 Pg. 105000-105010 (Dec 01 2017) ISSN: 1949-2553 [Electronic] United States
• PMID: 29285228 (Publication Type: Journal Article)