Optical imaging of the breast: evaluation of deoxyhemoglobin concentration alteration in 166 patients with suspicious breast lesions

Abstract

Background: We investigated the performance of optical imaging evaluating deoxyhemoglobin concentration alteration (DeHCA) in breast tissues.

Methods: We enrolled all consecutive patients from January 2015 to October 2016 with clinically suspicious and/or BI-RADS grade 3-5 lesions at mammography or ultrasound (US). Patients underwent optical imaging (ComfortScan) to evaluate for DeHCA. The reference standard was pathology from a surgical specimen for malignant lesions, pathology from a surgical specimen or core needle biopsy for benign lesions, and negative follow-up for contralateral negative breasts. Non-parametric statistics, receiver operating characteristic, and linear discrimination analyses were performed.

Results: Of 334 enrolled patients, 168 (50%) were excluded for technical problems and 166 (50%) (median age 52 years) were analyzed totaling 331 breasts and 176 lesions. Of these, 75 were benign (median size 19 mm) and 101 malignant (median size 20 mm). The median DeHCA score in malignant lesions (0.95, interquartile range [IQR] 1.00-0.87) was higher (p < 0.001) than in benign lesions (0.80, IQR 0.95-0.70). Using the optimal cutoff (0.85), DeHCA score was less accurate than mammography, US, and their combination, with 78% sensitivity, 52% specificity, 40% positive predictive value (PPV), and 85% negative predictive value (NPV); using a 0.8 cutoff, sensitivity reached 93% and NPV 91%, but specificity fell to 32% and PPV to 37%. The accuracy of DeHCA score linearly combined with mammography or US was higher than that of DeHCA score alone (p < 0.001) and not significantly higher than that of mammography or US alone.

Conclusions: DeHCA score was significantly higher in malignant than in benign lesions, but its accuracy was significantly lower than that of mammography or US. Future refinements are needed.

Keywords: Breast cancer; Breast ultrasound; Deoxyhemoglobin concentration alteration; Mammography; Optical imaging.

Fig. 1

Focality description: (a) blue diffusion area; (b) area with different colors (violet present); (c) area with different colors (no violet); (d) no focality

Fig. 2

Blue nipple: (a) overlap between nipple (blue cross) and lesion marker; (b) dark spot at the nipple

Fig. 3

Diffusion/sharpness of the focal area: (a) sharp focal area; (b) intermediate focal area; (c) diffused focal area

Fig. 4

Focal area dimension: calculation of both the general colored area (modeled by the red ellipse) and the lesion area (modeled by the yellow ellipse)

Fig. 5

Appearance time of the focal area

Fig. 6

Lesion curve typology: (a) waving; (b–d) rapidly descending; (e–g) slowly descending; (h) rapidly descending with bounce; (i) slowly descending with final bounce

Fig. 7

Comparison between the lesion curve and curves in other regions of the breast

Fig. 8

Bilaterality example: the comparison between the images of the two breasts show similar behavior

Fig. 9

Boxplot of DeHCA score to differentiate malignant versus non-malignant lesions

Fig. 10

ROC curve in the discrimination of breast diseases including non-malignant and malignant cases versus negative ones

Fig. 11

ROC curve to discriminate malignant lesions

Fig. 12

ROC curves for both linear classifiers (DeHCA score and mammography and DeHCA score and US) to (a) discriminate breast diseases versus negative cases and (b) differentiate malignant from non-malignant breast lesions

Fig. 13

Mammography appearance with prevalent, fibroglandular component most represented in the superior external quadrant, with consequent limited diagnostic definition. There is no obvious focal opacity. Instead, the DeHCA score was equal to 0.85. Final diagnosis: invasive ductal carcinoma

Fig. 14

Mammography (a) shows a heterogeneous finding with irregular edges of approximately 30 cm in diameter. DeHCA score (b) was equal to 0.92. At US (c), in the outer quadrant of the left breast, a hypoechoic nodule with irregular borders is visible, measuring 12 × 6 mm, with internal dot-like calcifications. Final diagnosis: invasive ductal carcinoma