Ontology highlight
ABSTRACT: Purpose
To examine circulating tumor DNA (ctDNA) and its association with residual cancer burden (RCB) using an ultrasensitive assay in patients with triple-negative breast cancer (TNBC) receiving neoadjuvant chemotherapy (NAT).Patients and methods
We identified responders (RCB-0/1) and matched non-responders (RCB-2/3) from the phase II TBCRC 030 prospective study of neoadjuvant paclitaxel vs. cisplatin in TNBC. We collected plasma samples at baseline, three weeks, and twelve weeks (end of therapy). We created personalized ctDNA assays utilizing MAESTRO mutation enrichment sequencing. We explored associations between ctDNA and RCB status and disease recurrence.Results
Of 139 patients, 68 had complete samples and no additional NAT. Twenty-two were responders and 19 of those had sufficient tissue for whole-genome sequencing. We identified an additional 19 non-responders for a matched case-control analysis of 38 patients using a MAESTRO ctDNA assay tracking 319-1000 variants (median 1000) to 114 plasma samples from 3 timepoints. Overall, ctDNA positivity was 100% at baseline, 79% at week 3, and 55% at week 12. Median tumor fraction (TFx) was 3.7 × 10 -4 (range: 7.9 × 10 -7 to 4.9 × 10 -1 ). TFx decreased 285-fold from baseline to week 3 in responders and 24-fold in non-responders. Week 12 ctDNA clearance correlated with RCB: clearance was observed in 10/11 patients with RCB-0, 3/8 with RCB-1, 4/15 with RCB-2, and 0/4 with RCB-3. Among 6 patients with known recurrence five had persistent ctDNA at week 12.Conclusion
NAT for TNBC reduced ctDNA TFx by 285-fold in responders and 24-fold in non-responders. In 58% (22/38) of patients, ctDNA TFx dropped below the detection level of a commercially available test, emphasizing the need for sensitive tests. Additional studies will determine if ctDNA-guided approaches can improve outcomes.
SUBMITTER: Parsons HA
PROVIDER: S-EPMC10029037 | biostudies-literature | 2023 Mar
REPOSITORIES: biostudies-literature

Parsons Heather A HA Blewett Timothy T Chu Xiangying X Sridhar Sainetra S Santos Katheryn K Xiong Kan K Abramson Vandana G VG Patel Ashka A Cheng Ju J Brufsky Adam A Rhoades Justin J Force Jeremy J Liu Ruolin R Traina Tiffany A TA Carey Lisa A LA Rimawi Mothaffar F MF Miller Kathy D KD Stearns Vered V Specht Jennifer J Falkson Carla C Burstein Harold J HJ Wolff Antonio C AC Winer Eric P EP Tayob Nabihah N Krop Ian E IE Makrigiorgos G Mike GM Golub Todd R TR Mayer Erica L EL Adalsteinsson Viktor A VA
medRxiv : the preprint server for health sciences 20230308
<h4>Purpose</h4>To examine circulating tumor DNA (ctDNA) and its association with residual cancer burden (RCB) using an ultrasensitive assay in patients with triple-negative breast cancer (TNBC) receiving neoadjuvant chemotherapy (NAT).<h4>Patients and methods</h4>We identified responders (RCB-0/1) and matched non-responders (RCB-2/3) from the phase II TBCRC 030 prospective study of neoadjuvant paclitaxel vs. cisplatin in TNBC. We collected plasma samples at baseline, three weeks, and twelve wee ...[more]