Diffuse optical spectroscopy for monitoring the responses of patients with breast cancer to neoadjuvant chemotherapy A meta-analysis

Background: This study aimed to investigate the potential of diffuse optical spectroscopy (DOT) for monitoring the responses of patients with breast cancer to neoadjuvant chemotherapy (NAC). Methods: We searched PubMed, EMBASE, Cochrane Database of Systematic Reviews, and Web of Science for relevant studies. Data were extracted for pooled analysis, heterogeneity testing, threshold effect testing, sensitivity analysis, publication bias analysis, and subgroup analysis. Results: The pooled meta-analysis of the 10 eligible studies that included 422 patients indicated the high performance of DOT for monitoring total patient responses to NAC (OR= 14.78, 95% CI: 8.23-26.54, P<.001), with low significant heterogeneity (I-2= 7.2%, P=.375). DOT possessed an area under the curve of 0.84 (95% CI: 0.81-0.87) to distinguish total patient responses to NAC. Subgroup analysis showed that the pooled sensitivity of DOT for monitoring pathologic complete response to NAC was 87%, and the pooled specificity was 70%. Meanwhile, the pooled sensitivity of DOT for monitoring pathologic complete and partial responses to NAC was 82%, and the pooled specificity was 82%. Although Begg's funnel plot (P=.049) indicated the presence of publication bias among the included studies, trim-and-fill method verified the stability of the pooled outcomes. Conclusion: Our meta-analysis of available published data indicated that DOT can be potentially used to predict and monitor patient responses to NAC. A larger study population is needed to fully assess the use of DOT for guiding therapies and predicting responses of individual subjects to NAC.