Intraoperative Resection Guidance with Photoacoustic and Fluorescence Molecular Imaging Using an Anti–B7-H3 Antibody-Indocyanine Green Dual Contrast Agent

Abstract

Breast cancer often requires surgical treatment including breast-conserving surgical resection. However, with current postsurgical histologic margin analysis, one quarter of breast cancer patients undergo reexcision to achieve negative margins corresponding to decreased local recurrence and better outcomes. Therefore, a method with high resolution and specificity for intraoperative margin assessment is needed. First, quantitative immunofluorescence staining of B7-H3 expression was assessed in four pathologic stages of breast cancer progression of the MMTV-PyMT transgenic murine model. Next, an antibody-dye contrast agent, B7-H3-ICG, was injected into mice prior to surgical resection of breast cancer. Anatomic ultrasound, spectroscopic photoacoustic (sPA), and fluorescence imaging were used to guide resection of mammary glands suspected of containing cancer. Resected tissues were processed for H&E staining and pathologic assessment and compared with sPA and fluorescence imaging signals. Tissue containing DCIS (46.0 ± 4.8 a.u.) or invasive carcinoma (91.7 ± 21.4 a.u.) showed significantly higher ( < 0.05) B7-H3 expression than normal and hyperplastic tissues (1.3 ± 0.8 a.u.). During image-guided surgical resection, tissue pieces assessed as normal or hyperplastic ( = 17) showed lower average sPA (3.17 ± 0.48 a.u.) and fluorescence signal [6.83E07 ± 2.00E06 (p/s)/(μW/cm²)] than DCIS and invasive carcinoma tissue ( = 63) with an average sPA signal of 23.98 ± 4.88 a.u. and an average fluorescence signal of 7.56E07 ± 1.44E06 (p/s)/(μW/cm²) with AUCs of 0.93 [95% confidence interval (CI), 0.87-0.99] and 0.71 (95% CI, 0.57-0.85), respectively.t was demonstrated that sPA and fluorescence molecular imaging combined with B7-H3-ICG agent can assess the disease status of tissues with high diagnostic accuracy, intraoperatively, with high resolution, sensitivity, and specificity. .

Evaluation of ductal carcinoma in situ grade via triple-modal molecular imaging of B7-H3 expression

“…The high specificity of photoacoustic imaging of the B7-H3 agent arises from the dynamic optical absorption spectrum of the B7-H3-ICG when binding to its molecular target. Photoacoustic imaging has the sensitivity to detect the changes in the optical absorption spectrum and suppress background signal from blood and unbound agent and this ability was verified through a multi-control study 24,26 . While the required imaging depth was limited in this study due to the superficial and small nature of murine mammary glands, photoacoustic imaging was able to provide high-resolution images of optical contrast at depth within the glands.…”

“…Aside from detecting and monitoring DCIS for screening purposes, it is also critical to be able to do so in the intraoperative setting to ensure negative margins. Significant research effort is currently dedicated to implementing fluorescence and photoacoustic imaging for intraoperative guidance 26,[39][40][41] . Here, photoacoustic molecular imaging combined with the B7-H3-ICG contrast agent was shown to be able to detect small foci of DCIS in a murine model of breast cancer development.…”

“…It was shown previously that combined photoacoustic (PA) and fluorescent molecular imaging using an anti-B7-H3 antibody-near infrared dye (indocyanine green) conjugate (B7-H3-ICG) could differentiate clinically actionable breast carcinomas from normal mammary tissues in a transgenic murine model of breast cancer 24,26 . Photoacoustic imaging, utilizing the photoacoustic effect of generating sound waves subsequent to absorption of nanosecond pulses of light 27,28 , allows for high-resolution imaging of optical absorption at depth (up to 5 cm), while fluorescence imaging, lacking background signal, provides high sensitivity to the contrast agent and mimics a surgeon's field of view.…”

CLPTM1L induces estrogen receptor β signaling-mediated radioresistance in non-small cell lung cancer cells

“…Immunofluorescence staining was performed as described previously [57]. After 48 h of transfection (24 h of 4 Gy IR), the cells were fixed with paraformaldehyde, and permeabilized with 0.1% Triton X-100 in PBS.…”

Current concepts in nanostructured contrast media development for in vivo photoacoustic imaging

“…Later, in 2018, Wilson et al employed antibody-conjugated ICG for intraoperative photoacoustic and dual fluorescence imaging of breast cancer to help the surgeon during the removal of tumoral tissues for minimizing positive resection margins. 180 In 2015, Garcia-Uribe et al employed methylene blue for the same application in a clinical trial on Fig. 8 Monomeric units principally employed in semiconducting polymers for PA imaging.…”