Hemodynamic signature of breast cancer under fractional mammographic compression using a dynamic diffuse optical tomography system

Abstract

Near infrared dynamic diffuse optical tomography measurements of breast hemodynamics during fractional mammographic compression offer a novel contrast mechanism for detecting breast cancer and monitoring chemotherapy. Tissue viscoelastic relaxation during the compression period leads to a slow reduction in the compression force and reveals biomechanical and metabolic differences between healthy and lesion tissue. We measured both the absolute values and the temporal evolution of hemoglobin concentration during 25-35 N of compression for 22 stage II and III breast cancer patients scheduled to undergo neoadjuvant chemotherapy. 17 patients were included in the group analysis (average tumor size 3.2 cm, range: 1.3-5.7 cm). We observed a statistically significant differential decrease in total and oxy-hemoglobin, as well as in hemoglobin oxygen saturation in tumor areas vs. healthy tissue, as early as 30 seconds into the compression period. The hemodynamic contrast is likely driven by the higher tumor stiffness and different viscoelastic relaxation rate, as well as the higher tumor oxygen metabolism rate. References and links 1. Cancer Facts & Figs. 2013 (American Cancer Society, Atlanta, 2013

Normalization of compression-induced hemodynamics in patients responding to neoadjuvant chemotherapy monitored by dynamic tomographic optical breast imaging (DTOBI)

“…1) consists of a high temporal resolution, hybrid continuous wave/frequency domain transmission mode diffuse optical tomography system. The optical instrumentation is integrated into a compression setup also equipped with a Tekscan I-Scan pressure mapping system [44]. The frequency domain component consists of an ISS Imagent (model 96208, ISS Inc., Champaign, IL).…”

“…A full description of the experimental setup has been previously published by our group [44]. In summary, the breast is placed between two horizontal parallel plates (equivalent to mammographic craniocaudal (CC) compression), which apply a repeated step compression/release to the breast.…”

“…Both gas inhalation/breath-holding [36,37] and external mechanical stimuli [38][39][40][41][42][43][44][45][46] have been proposed to develop novel imaging biomarkers of breast cancer. In particular, our group has obtained promising initial results by dynamically imaging the breast tissue response to fractional mammographic compression [47,48].Tissue viscoelastic relaxation during the compression period leads to a slow reduction in the compression force and reveals biomechanical and metabolic differences between normal and lesion tissue.…”

“…In particular, our group has obtained promising initial results by dynamically imaging the breast tissue response to fractional mammographic compression [47,48].Tissue viscoelastic relaxation during the compression period leads to a slow reduction in the compression force and reveals biomechanical and metabolic differences between normal and lesion tissue. Using this method, we have shown that there is a significant difference in the hemodynamic response to compression between the tumor area and the surrounding normal tissue in a group of seventeen breast cancer patients [44].…”

Frequency domain near-infrared multiwavelength imager design using high-speed, direct analog-to-digital conversion

“…The lengthy measurement is a result of sequential cycling through both laser wavelengths and output fibers, where sufficient integration time is needed for each data point to overcome the inherently lower signal-to-noise ratio (SNR) of RF measurements. The need to improve these long acquisition times has become more important recently with the increased use of dynamic breast optical tomography to characterize the breast tissue response to external stimuli 20,21 which requires obtaining a full dataset at least every few seconds.…”