Clinical and pathological characteristics of all the 105 patients enrolled in the clinical study. Patients highlighted (n=17) were excluded from statistical analysis due to the main reasons: patient withdrew from the study (n=4) (blue color); baseline DOTBIS measurement not collected due to instrumentation failure (n=8) (grey color); patient under investigational and not FDA approved drug regimen (n=1) (green color); and machine operator error (n=4) (yellow color).
ARTICLE ABSTRACT
This study's primary objective was to evaluate the changes in optically derived parameters acquired with a diffuse optical tomography breast imaging system (DOTBIS) in the tumor volume of patients with breast carcinoma receiving neoadjuvant chemotherapy (NAC).
In this analysis of 105 patients with stage II–III breast cancer, normalized mean values of total hemoglobin (ctTH{b_N}$), oxyhemoglobin (ct{O_2}H{b_N}$), deoxy-hemoglobin concentration (ctHH{b_N}$), water, and oxygen saturation (St{O_2}_N$) percentages were collected at different timepoints during NAC and compared with baseline measurements. This report compared changes in these optical biomarkers measured in patients who did not achieve a pathologic complete response (non-pCR) and those with a pCR. Differences regarding molecular subtypes were included for hormone receptor–positive and HER2-negative, HER2-positive, and triple-negative breast cancer.
At baseline, ctHH{b_N}$ was higher for pCR tumors (3.97 ± 2.29) compared with non-pCR tumors (3.00 ± 1.72; P = 0.031). At the earliest imaging point after starting therapy, the mean change of ctHH{b_N}$ compared with baseline ({\Delta _{TP1}}ctHH{b_N}$) was statistically significantly higher in non-pCR (1.23 ± 0.67) than in those with a pCR (0.87 ± 0.61; P < 0.0005), and significantly correlated to residual cancer burden classification (r = 0.448; P < 0.0005). {\Delta _{TP1}}ctHH{b_N}$ combined with HER2 status was proposed as a two-predictor logistic model, with AUC = 0.891; P < 0.0005; and 95% confidence interval, 0.812–0.969.
This study demonstrates that DOTBIS measured features change over time according to tumor pCR status and may predict early in the NAC treatment course whether a patient is responding to NAC.
