Clinicopathological and prognostic impact of imaging of breast cancer angiogenesis and hypoxia using diffuse optical spectroscopy

Prediction of disease-free survival using strain elastography and diffuse optical tomography in patients with T1 breast cancer: a 10-year follow-up study

BACKGROUND

Early-stage breast cancer (BC) presents a certain risk of recurrence, leading to variable prognoses and complicating individualized management. Yet, preoperative noninvasive tools for accurate prediction of disease-free survival (DFS) are lacking. This study assessed the potential of strain elastography (SE) and diffuse optical tomography (DOT) for non-invasive preoperative prediction of recurrence in T1 BC and developed a prediction model for estimating the probability of DFS.

METHODS

A total of 565 eligible patients with T1 invasive BC were enrolled prospectively and followed to investigate the recurrence. The associations between imaging features and DFS were evaluated and a best-prediction model for DFS was developed and validated.

RESULTS

During the median follow-up period of 10.8 years, 77 patients (13.6%) developed recurrences. The fully adjusted Cox proportional hazards model showed a significant trend between an increasing strain ratio (SR) (P < 0.001 for trend) and the total hemoglobin concentration (TTHC) (P = 0.001 for trend) and DFS. In the subgroup analysis, an intensified association between SR and DFS was observed among women who were progesterone receptor (PR)-positive, lower Ki-67 expression, HER2 negative, and without adjuvant chemotherapy and without Herceptin treatment (all P < 0.05 for interaction). Significant interactions between TTHC status and the lymphovascular invasion, estrogen receptor (ER) status, PR status, HER2 status, and Herceptin treatment were found for DFS(P < 0.05).The imaging-clinical combined model (TTHC + SR + clinicopathological variables) proved to be the best prediction model (AUC = 0.829, 95% CI = 0.786-0.872) and was identified as a potential risk stratification tool to discriminate the risk probability of recurrence.

CONCLUSION

The combined imaging-clinical model we developed outperformed traditional clinical prognostic indicators, providing a non-invasive, reliable tool for preoperative DFS risk stratification and personalized therapeutic strategies in T1 BC. These findings underscore the importance of integrating advanced imaging techniques into clinical practice and offer support for future research to validate and expand on these predictive methodologies.

Optical Breast Imaging: A Review of Physical Principles, Technologies, and Clinical Applications

Optical imaging involves the propagation of light through tissue. Current optical breast imaging technologies, including diffuse optical spectroscopy, diffuse optical tomography, and photoacoustic imaging, capitalize on the selective absorption of light in the near-infrared spectrum by deoxygenated and oxygenated hemoglobin. They provide information on the morphological and functional characteristics of different tissues based on their varied interactions with light, including physiologic information on lesion vascular content and anatomic information on tissue vascularity. Fluorescent contrast agents, such as indocyanine green, are used to visualize specific tissues, molecules, or proteins depending on how and where the agent accumulates. In this review, we describe the physical principles, spectrum of technologies, and clinical applications of the most common optical systems currently being used or developed for breast imaging. Most notably, US co-registered photoacoustic imaging and US-guided diffuse optical tomography have demonstrated efficacy in differentiating benign from malignant breast masses, thereby improving the specificity of diagnostic imaging. Diffuse optical tomography and diffuse optical spectroscopy have shown promise in assessing treatment response to preoperative systemic therapy, and photoacoustic imaging and diffuse optical tomography may help predict tumor phenotype. Lastly, fluorescent imaging using indocyanine green dye performs comparably to radioisotope mapping of sentinel lymph nodes and appears to improve the outcomes of autologous tissue flap breast reconstruction.

The diagnostic performance of dynamic contrast-enhanced MRI and its correlation with subtypes of breast cancer

To evaluate diagnostic performance of perfusion-weighted imaging in differentiating benign from malignant breast lesions, and the correlation between the prognostic factors/subtypes of breast cancers and the perfusion parameters.A total of 76 patients (59 cases with breast cancer) were included in our study. The Wilcoxon rank-sum test or the Kruskal-Wallis test were adopted for comparisons according to the dichotomous histopathologic prognostic factors or immunohistochemical subtypes. Receiver operating characteristic curves were used to determine the area under the curve (AUC) values for perfusion parameters to assess discrimination ability.Confirming by pathology after operation, the percentage of benign lesions is 22.37% (17/76), malignant lesions (breast cancer) is 77.63% (59/76). According to puncture and pathological findings after operation, the standard of the molecular subtypes of breast cancer, triple negative account for 13.6% (8/59), non-triple negative account for 86.4% (51/59). The value of mean Ktrans and Kep were lower in benign than malignant lesions (P ≤ .001). The AUC of the 3 indicators are significantly improved after adjusting for age (AUC = 0.858 for Ktrans, AUC = 0.926 for Kep, and AUC = 0.827 for Ve). Moreover, the Ve index showed better discrimination performance than other indicators in identifying patients with triple-negative subtypes. Similarly, the identification ability came to the highest when combing Kep and Ve.Perfusion parameters on dynamic enhanced magnetic resonance imaging are statistically significant in distinguishing benign from malignant breast lesion, and may potentially be used as biomarkers in discriminating patients with triple-negative molecular subtypes of breast cancer.

A bench-top model of middle ear effusion diagnosed with optical tympanometry

OBJECTIVES

To assess the validity of a bench-top model of an optical tympanometry device to diagnose in vitro model of middle ear effusion (MEE).

METHODS AND MATERIALS

We illuminated an in vitro model of ear canal and tympanic membrane with broadband light and relayed remitted light to a spectrometer system. We then used our proprietary algorithm to extract spectral features that, together with our logistic regression classifiers, led us to calculate a set of simplified indices related to different middle ear states. Our model included a glass vial covered with a porcine submucosa (representing the tympanic membrane) and filled with air, water, or milk solution (representing different MEE), and a set of cover-glass slips filled with either blood (representing erythema) or cerumen. By interchanging fluid types and cover-glass slips, we made measurements on combinations corresponding to normal healthy ear and purulent or serous MEE.

RESULTS

Each simulated condition had a distinct spectral profile, which was then employed by our algorithm to discriminate clean and cerumen-covered purulent and serous MEE. Two logistic purulent and serous MEE classifiers correctly classified all in vitro middle ear states with 100% accuracy assessed by leave-one-out and k-fold cross validation.

CONCLUSIONS

This proof-of-concept in vitro study addressed an unmet need by introducing a device that easily and accurately can assess middle ear effusion. Future in vivo studies aimed at collecting data from clinical settings are warranted to further elucidate the validity of the technology in diagnosing pediatric acute otitis media.

Near-Infrared Spectroscopy in Bio-Applications

Near-infrared (NIR) spectroscopy occupies a specific spot across the field of bioscience and related disciplines. Its characteristics and application potential differs from infrared (IR) or Raman spectroscopy. This vibrational spectroscopy technique elucidates molecular information from the examined sample by measuring absorption bands resulting from overtones and combination excitations. Recent decades brought significant progress in the instrumentation (e.g., miniaturized spectrometers) and spectral analysis methods (e.g., spectral image processing and analysis, quantum chemical calculation of NIR spectra), which made notable impact on its applicability. This review aims to present NIR spectroscopy as a matured technique, yet with great potential for further advances in several directions throughout broadly understood bio-applications. Its practical value is critically assessed and compared with competing techniques. Attention is given to link the bio-application potential of NIR spectroscopy with its fundamental characteristics and principal features of NIR spectra.

Long non-coding RNA NKILA inhibited angiogenesis of breast cancer through NF-κB/IL-6 signaling pathway

OBJECTIVE

The relationship between NF-κB Interacting lncRNA (NKILA) and angiogenesis in breast cancer has never been studied. Our study aimed to investigate effect of NKILA on proliferation, migration, apoptosis, as well as angiogenesis in breast cancer.

METHODS

NKILA was over-expressed in MDA-MB-231 cells by transfection of pcDNA3.1-NKILA vector. Cell viability, apoptosis and migration were measured by MTT, flow cytometry and wound healing assays, respectively. Angiogenesis of human umbilical vein endothelial cells (HUVEC) was measured using tube formation assay. The expression levels of NKILA, IL-6, VEGFA, VEGFR, apoptosis and epithelial-mesenchymal transition (EMT) and NF-κB/IL-6 signaling-related markers were determined using qRT-PCR or Western blotting.

RESULTS

Cell viability and migration of MDA-MB-231 cells were significantly inhibited, while cell apoptosis was obviously promoted by overexpression of NKILA. Overexpression of NKILA could also inhibit the phosphorylation of IκBα and the nuclear transposition of p65, as well as induce cell apoptosis-related proteins and inhibit epithelial-mesenchymal transition-related proteins. Cell viability and migration of HUVEC were also significantly inhibited when treated with supernatant of cells overexpressed NKILA or treated with BAY11-7028. Exogenous IL-6 significantly increased the cell viability and migration of HUVEC, and overexpression of NKILA could reverse these effects induced by IL-6. Overexpression of NKILA significantly inhibited the protein levels of IL-6 and VEGFA in supernatant, as well as VEGFR in HUVEC, thus inhibited the angiogenesis of HUVEC. NKILA also reversed the above effects on protein levels of IL-6 and VEGFA in supernatant and angiogenesis induced by exogenous IL-6.

CONCLUSION

Overexpression of NKILA could inhibit cell proliferation, migration and promote apoptosis of breast cancer cells. It could also inhibit cell proliferation, migration and angiogenesis of HUVEC through inhibiting IL-6 secretion via NF-κB signaling pathway.

Bevacizumab Induces Acute Hypoxia and Cancer Progression in Patients with Refractory Breast Cancer: Multimodal Functional Imaging and Multiplex Cytokine Analysis

Purpose: Bevacizumab, an antibody against endothelial growth factor, is a key but controversial drug in the treatment of metastatic breast cancer. We, therefore, aimed to determine the intrinsic resistance to bevacizumab at the physiologic and molecular levels in advanced breast cancer using PET, dynamic contrast-enhanced MRI, diffuse optical spectroscopic imaging (DOSI), and multiplex cytokine assays.Experimental Design: In total, 28 patients diagnosed with advanced stage III/IV breast cancer receiving single-agent bevacizumab for 1 week followed by paclitaxel combined with bevacizumab underwent ¹⁸F-fluorodeoxyglucose (FDG)-PET, ¹⁸F-fluoromisonidazole (FMISO)-PET, and MRI at both baseline and two courses after treatment initiation. Hemodynamic measurement using DOSI and blood sample collection were performed at baseline and multiple times during the first week after the initiation of single-agent bevacizumab. We distinguished nonresponders from responders by serial FDG-PET based on their glycolytic changes to chemotherapy.Results: Nonresponders showed significantly higher hypoxic activity on FMISO-PET and less tumor shrinkage than responders. Hemodynamic parameters showed higher tumor blood volume and a remarkable decrease in the tissue oxygen level in nonresponders compared with responders after the infusion of single-agent bevacizumab. Multiplex cytokine assays revealed increased plasma levels of both proangiogenic and hypoxia-related inflammatory cytokines in nonresponders and decreased levels in responders.Conclusions: Nonresponders exhibited a higher degree of angiogenesis with more severe hypoxia than responders during bevacizumab treatment. These findings demonstrated that the addition of bevacizumab to paclitaxel treatment under hypoxic conditions could be ineffective and may result in acute hypoxia and increased cytokine secretion associated with cancer progression. Clin Cancer Res; 23(19); 5769-78. ©2017 AACR.

Visualization of tumor-related blood vessels in human breast by photoacoustic imaging system with a hemispherical detector array

Noninvasive measurement of the distribution and oxygenation state of hemoglobin (Hb) inside the tissue is strongly required to analyze the tumor-associated vasculatures. We developed a photoacoustic imaging (PAI) system with a hemispherical-shaped detector array (HDA). Here, we show that PAI system with HDA revealed finer vasculature, more detailed blood-vessel branching structures, and more detailed morphological vessel characteristics compared with MRI by the use of breast shape deformation of MRI to PAI and their fused image. Morphologically abnormal peritumoral blood vessel features, including centripetal photoacoustic signals and disruption or narrowing of vessel signals, were observed and intratumoral signals were detected by PAI in breast cancer tissues as a result of the clinical study of 22 malignant cases. Interestingly, it was also possible to analyze anticancer treatment-driven changes in vascular morphological features and function, such as improvement of intratumoral blood perfusion and relevant changes in intravascular hemoglobin saturation of oxygen. This clinical study indicated that PAI appears to be a promising tool for noninvasive analysis of human blood vessels and may contribute to improve cancer diagnosis.

In vivo imaging of eribulin-induced reoxygenation in advanced breast cancer patients: a comparison to bevacizumab

Background:

Eribulin mesylate (eribulin) is a first-in-class halichondrin B-based microtubule dynamics inhibitor. To compare the anti-angiogenic activity of eribulin to that of bevacizumab, we compared tumour vessel remodelling and reoxygenation between the two agents.

Methods:

Patients with advanced breast cancer with stage III/IV were eligible for the study. Patients were assigned to receive either eribulin or single-agent bevacizumab. Tissue concentrations of oxyhaemoglobin (O₂Hb) and deoxyhaemoglobin (HHb), and oxygen saturation (SO₂) of breast tumours before and day 7 after the first infusion were repeatedly measured using diffuse optical spectroscopic imaging (DOSI). A pair of blood samples was collected for multiplex biomarker studies.

Results:

Baseline DOSI measurement of all 29 patients (eribulin, n=14 and bevacizumab, n=15) revealed significantly higher tumour concentrations of O₂Hb and HHb than that in the normal breast tissue. After eribulin treatment, DOSI revealed a significant decrease in HHb concentration and increased SO₂ during the observation period. This trend was not observed for bevacizumab. Instead, bevacizumab significantly decreased the concentration of O₂Hb. The multiplex biomarker study revealed that both eribulin and bevacizumab decreased plasma concentrations of VEGF and bFGF, but only eribulin treatment suppressed the plasma concentration of TGF-β1.

Conclusions:

Eribulin, but not bevacizumab, treatment increased tumour SO₂. Suppression of TGF-β1 by eribulin could have a favourable anti-angiogenic effect. Our results suggest that differences in vascular remodelling between these two agents may account for their different effects on tumour reoxygenation.

Clinical Report on the First Prototype of a Photoacoustic Tomography System with Dual Illumination for Breast Cancer Imaging

Photoacoustic tomography is a recently developed imaging modality that can provide high spatial-resolution images of hemoglobin distribution in tissues such as the breast. Because breast cancer is an angiogenesis-dependent type of malignancy, we evaluated the clinical acceptability of breast tissue images produced using our first prototype photoacoustic mammography (PAM) system in patients with known cancer. Post-excisionally, histological sections of the tumors were stained immunohistochemically (IHC) for CD31 (an endothelial marker) and carbonic anhydrase IX (CAIX) (a marker of hypoxia). Whole-slide scanning and image analyses were used to evaluate the tumor microvessel distribution pattern and to calculate the total vascular perimeter (TVP)/area for each lesion. In this clinical study, 42 lesions were primarily scanned using PAM preoperatively, three of which were reported to be benign and were excluded from statistical analysis. Images were produced for 29 out of 39 cancers (visibility rate = 74.4%) at the median depth of 26.5 (3.25-51.2) mm. Age, menopausal status, body mass index, history of neoadjuvant treatment, clinical stage and histological tumor angiogenesis markers did not seem to affect the visibility. The oxygen saturation level in all of the measured lesions was lower than in the subcutaneous counterpart vessels (Wilcoxon test, p value<0.001), as well as in the counterpart contralateral normal breast region of interest (ROI) (Wilcoxon test, p value = 0.001). Although the oxygen saturation level was not statistically significant between CAIX-positive vs. -negative cases, lesional TVP/area showed a positive correlation with the oxygen saturation level only in the group that had received therapy before PAM. In conclusion, the vascular and oxygenation data obtained by PAM have great potential for identifying functional features of breast tumors.

Effect of the chest wall on the measurement of hemoglobin concentrations by near-infrared time-resolved spectroscopy in normal breast and cancer

BACKGROUND

Optical imaging and spectroscopy using near-infrared light have great potential in the assessment of tumor vasculature. We previously measured hemoglobin concentrations in breast cancer using a near-infrared time-resolved spectroscopy system. The purpose of the present study was to evaluate the effect of the chest wall on the measurement of hemoglobin concentrations in normal breast tissue and cancer.

METHODS

We measured total hemoglobin (tHb) concentration in both cancer and contralateral normal breast using a near-infrared time-resolved spectroscopy system in 24 female patients with breast cancer. Patients were divided into two groups based on menopausal state. The skin-to-chest wall distance was determined using ultrasound images obtained with an ultrasound probe attached to the spectroscopy probe.

RESULTS

The apparent tHb concentration of normal breast increased when the skin-to-chest wall distance was less than 20 mm. The tHb concentration in pre-menopausal patients was higher than that in post-menopausal patients. Although the concentration of tHb in cancer tissue was statistically higher than that in normal breast, the contralateral normal breast showed higher tHb concentration than cancer in 9 of 46 datasets. When the curves of tHb concentrations as a function of the skin-to-chest wall distance in normal breast were applied for pre- and post-menopausal patients separately, all the cancer lesions plotted above the curves.

CONCLUSIONS

The skin-to-chest wall distance affected the measurement of tHb concentration of breast tissue by near-infrared time-resolved spectroscopy. The tHb concentration of breast cancer tissue was more precisely evaluated by considering the skin-to-chest wall distance.