In vivo absorption, scattering, and physiologic properties of 58 malignant breast tumors determined by broadband diffuse optical spectroscopy

Abstract

Diffuse optical imaging (DOI) may be a beneficial diagnostic method for women with mammographically dense breast tissue. In order to evaluate the utility of DOI, we are developing broadband diffuse optical spectroscopy (DOS) to characterize the functional origins of optical signals in breast cancer patients. Broadband DOS combines multifrequency intensity-modulated and continuous-wave near-infrared light to quantify tissue absorption and scattering spectra from 650 to 1000 nm. Values of intrinsic physiological properties (oxy- and deoxy-hemoglobin, water, lipid, and scatter power) derived from absorption and scattering spectra provide detailed information on breast physiology. We present the results of clinical studies of 58 stage II/III malignant breast tumors using a noninvasive, handheld, broadband DOS probe. On average, eight positions were scanned over tumor and contralateral normal breast for each subject. Intrinsic physiological properties were statistically significantly different for malignant vs. normal tissues for all subjects, without patient age or tumor size/type stratification. Breast tissues containing malignant tumors displayed reduced lipid content ( approximately 20%) and increased water, deoxy-, and oxy-hemoglobin (>50% each) compared to normal breast tissues. Functional perturbations by the tumor were significantly larger than functional variations in normal tissues. A tissue optical index (TOI) derived from intrinsic physiological properties yielded an average two-fold contrast difference between malignant tumors and intrinsic tissue properties. Our results demonstrate that intrinsic optical signals can be influenced by functional perturbations characteristic of malignant transformation; cellular metabolism, extracellular matrix composition, and angiogenesis. Our findings further underscore the importance of broadband measurements and patient age stratification in breast cancer DOI.

Diffuse optical tomography of the breast: preliminary findings of a new prototype and comparison with magnetic resonance imaging

“…Intra-and interobserver agreement were good to excellent, indicating a reproducible method. Our results are in agreement with previously published studies using different techniques [11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26]. Detection rates ranging from 0.04 to 1.00 were reported, irrespective of lesion classification (benign/malignant).…”

Near‐infrared imaging of breast cancer using optical contrast agents

“…Several investigators report an increase in diagnostic accuracy. Using diffuse optical spectroscopy (DOS) Cerussi et al [110] found intrinsic physiologic features of malignancy to significantly differ from normal glandular breast tissue: all malignant lesions had lower lipid content than normal breast tissue but higher water, desoxy-, and oxyhemoglobin content. Zhu et al [32] and Fang et al [111] also report significant differences in hemoglobin concentration between malignant and benign lesions.…”

A wireless handheld probe with spectrally constrained evolution strategies for diffuse optical imaging of tissue

“…The ranges for μ a and μ s were selected based on the typical optical properties of breast tissue. 4 In the first experiment, we used a reference solution of 3.2% by volume (32 ml/l) of Intralipid R 20% with no added ink or dye. This provides a medium where the absorption is predominantly due to water, which results in higher absorption at higher wavelengths (expected 0.042, 0.068, cm −1 @ 780, 808, 850, 904 nm).…”

“…[4][5][6][7] These handheld probes image in reflectance mode with a 0.5-3.5 cm sourcedetector separation in order to probe beneath the tissue surface. They use a range of near-infrared wavelengths to determine the concentration of chromophores relevant to detecting tumors including oxy-and deoxy-hemoglobin, lipid, water, and scattering.…”