Scanning elastic scattering spectroscopy detects metastatic breast cancer in sentinel lymph nodes

Abstract

Abstract.A novel method for rapidly detecting metastatic breast cancer within excised sentinel lymph node͑s͒ of the axilla is presented. Elastic scattering spectroscopy ͑ESS͒ is a point-contact technique that collects broadband optical spectra sensitive to absorption and scattering within the tissue. A statistical discrimination algorithm was generated from a training set of nearly 3000 clinical spectra and used to test clinical spectra collected from an independent set of nodes. Freshly excised nodes were bivalved and mounted under a fiber-optic plate. Stepper motors rasterscanned a fiber-optic probe over the plate to interrogate the node's cut surface, creating a 20ϫ 20 grid of spectra. These spectra were analyzed to create a map of cancer risk across the node surface. Rules were developed to convert these maps to a prediction for the presence of cancer in the node. Using these analyses, a leave-one-out crossvalidation to optimize discrimination parameters on 128 scanned nodes gave a sensitivity of 69% for detection of clinically relevant metastases ͑71% for macrometastases͒ and a specificity of 96%, comparable to literature results for touch imprint cytology, a standard technique for intraoperative diagnosis. ESS has the advantage of not requiring a pathologist to review the tissue sample.

Evaluation of breast tissue with confocal strip-mosaicking microscopy: a test approach emulating pathology-like examination

“…[1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19] Confocal microscopy is an emerging technology for rapid imaging of freshly excised tissue without the need for frozen-or fixed-section processing. Initial studies have described the major findings of invasive breast cancers using fluorescence confocal microscopy.…”

Structured light scatteroscopy

“…While these absorbers can be diagnostically powerful, in many situations, such as in surgery, the ability to remove the effects of absorption (e.g., from the presence of surface blood) from the image and to simply visualize scatter changes would be valuable. Several confocal and specialized fiber-based scanning approaches 3,4 have been developed to probe or image optical property variations in cells and tissue surfaces. But almost all these techniques rely on semianalytical or empirical light-transport models to separate absorption effects from scattering.…”

Scanning in situ Spectroscopy platform for imaging surgical breast tissue specimens

“…Direct adaptations of probe-based approaches to imaging can involve mechanically scanning or positioning the probe head across the tissue surface, which is time consuming and does not scale well for efficient wide field imaging of large tissue specimens, that is needed for comprehensive margin assessment [7][8][9][10][11]. Similarly, scanning confocal approaches offer sufficient signal localization and imaging capabilities in a scalable, non-contact design that can help characterize tissue heterogeneity effectively.…”