Eur J Cancer: Circulating tumor DNA (ctDNA) to identify EGFR-mutated NSCLC who benefited from continuous EGFR-TKI treatment

Osimertinib is a third-generation EGFR-TKI inhibitor.

Therefore, a retrospective, multi-center, observational study from the Spanish Lung Cancer Group (SLCG) used digital polymerase chain reaction (dPCR) to detect ctDNA to evaluate the prognostic value of ctDNA in EGFR+NSCLC patients using EGFR-TKI treatment .

A total of 228 patients from 25 research centers were included in the study, and a total of 830 blood samples were analyzed.

The median follow-up time was 28.

189 patients were treated with first- or second-generation TKIs in the first line, and low-risk patients were defined as pre-treatment mutant allele frequency (MAF) <7%.

PFS and OS in low-risk patients and responders

PFS and OS in low-risk patients

High-response patients were defined as MAF <7% at diagnosis and ctDNA negative at 3 or 6 months after treatment.

OS of low-risk and high-response patients with different TKI treatment sequence

However, there is no significant difference in the order of TKI in low-risk patients with OS.

OS in low-risk patients with different TKI treatment sequence

In summary, the level of ctDNA before treatment helps to identify low-risk patients, so as to benefit from continuous treatment of EGFR-TKI.

Mariano Provencio, Roberto Serna-Blasco, Fabio Franco, et al.