Serial circulating tumor DNA identification associated with the efficacy and prognosis of neoadjuvant chemotherapy in breast cancer

Circulating tumor DNA (ctDNA) provides a promising noninvasive alternative to evaluate the efficacy of neoadjuvant chemotherapy (NCT) in breast cancer. Herein, we collected 63 tissue (aspiration biopsies and resected tissues) 206 blood samples (baseline, during (Chemo), after (Post-Chemo), operation (Post-Op), follow-up) from 32 patients, preformed targeted deep sequencing with customed 1021-gene panel. As results, TP53 (43.8%) PIK3CA (40.6%) were most common mutant genes primary tumors. At least one tumor-derived mutation was detected following number samples: 21, baseline; 3, Chemo; 9, Post-Chemo; 5, Post-Op. Four patients pathologic complete response had no Chemo Post-Chemo blood. Compared mutation-positive or blood, counterparts showed superior decrease (median, 86.5% versus 54.6%) lymph involvement 1 3.5). All five Post-Op developed distant metastases follow-up, sensitivity detecting clinically relapsed 71.4% (5/7). The median DFS 9.8 months for but not reached others (HR 23.53; 95% CI, 1.904–290.9; p < 0.0001). Our study shows that sequential monitoring ctDNA an effective method evaluating NCT patient recurrence. Integrating profiling into management LABC might improve clinical outcome. This prospective recruited at Peking Union Medical College Hospital (ClinicalTrials.gov Identifier: NCT02797652).