To investigate the clinical value of conventional ultrasonographic (US), US-guided diffuse optical tomography (US-guided DOT) and both combined to assess treatment response of breast cancer to neoadjuvant chemotherapy(NAC).

Eighty-eight breast cancer patients, totally 93 lesions were included in the study. Pre- and post-last chemotherapy, size, and total hemoglobin concentration (THC) of each lesion were measured by conventional US and US-guided DOT before biopsy, the change of lesion Size(ΔSize) and the change of THC(ΔTHC) were calculated respectively. Based on the guidelines to evaluate the response to treatment in solid tumors, the responses to NAC were classified into complete response, partial response, static disease, progressive disease groups. The histological response to chemotherapy were categorised as partial pathological response and complete pathological response using Miller and Payne system.

Of 93 breast cancers, the overall response rate was 81.7%, the cPR rate was 24.7%. According to ROC curve analysis, when ΔSize 42.6% and ΔTHC 23.9% as cutoff values to evaluate the complete response and partial response, the area under the curve (AUC) were 0.666 and 0.751, respectively, the AUC of US and US-guided DOT combined in parallel and in series were 0.680 and 0.737 respectively. When ΔSize 64.5% and ΔTHC 27.2% as cutoff values to evaluate complete pathologial response, the AUC were 0.690 and 0.728 respectively, the AUC of US and US-guided DOT combined in parallel and in series were 0.693 and 0.726 respectively.

US-guided DOT and US can be used to predict breast cancers response to NAC, US and US-guided DOT combined in parallel and in series can not improve response prediction comparing with US or US-guided DOT alone.

Ultrasonography; Diffuse optical tomography; Breast carcinoma; Neoadjuvant Chemotherapy; Total hemoglobin concentration