Background: Neoadjuvant chemotherapy (NAC) is widely administered in the primary treatment of triple-negative breast cancer (TNBC). However, serum biomarkers for evaluating or monitoring the curative efficacy of NAC have not been established. Accumulating data have shown that soluble programmed death 1 (sPD-1) and its ligand (sPD-L1) might be potential biomarkers for evaluating the curative efficacy of chemotherapy and patient prognosis in several cancers but not yet in breast cancer.
Patients and methods: Blood specimens were obtained from 66 TNBC patients who received NAC and 59 healthy women. The serum concentrations of sPD-1 and sPD-L1 were measured by enzyme-linked immunosorbent assay.
Results: Compared to healthy women, the serum concentration of sPD-1 was significantly elevated in TNBC patients before NAC (549.3 ± 58.76 pg/mL vs. 379.2 ± 17.30 pg/mL, P = .007), but there was only an increase tendency for sPD-L1 (227.7 ± 23.99 pg/mL vs. 195.0 ± 8.49 pg/mL, P = .22). The serum levels of sPD-1 and sPD-L1 before NAC in TNBC patients increased with tumor stage (P = .038 and .030, respectively). Patients who experienced complete or partial remission after NAC had significantly decreased serum levels of sPD-1 and sPD-L1 compared to patients with a poor response to NAC (P = .019 and .021, respectively).
Conclusion: Serum levels of sPD-1 and sPD-L1 could be used as noninvasive biomarkers for evaluating the malignancy of TNBC before NAC and for predicting the NAC response in TNBC patients.
Keywords: Biomarker; Neoadjuvant chemotherapy; Soluble programmed death 1; Soluble programmed death ligand 1; Triple negative breast cancer.
Copyright © 2019. Published by Elsevier Inc.