Portable Optical Fiber Probe-Based Spectroscopic Scanner for Rapid Cancer Diagnosis: A New Tool for Intraoperative Margin Assessment

Abstract

There continues to be a significant clinical need for rapid and reliable intraoperative margin assessment during cancer surgery. Here we describe a portable, quantitative, optical fiber probe-based, spectroscopic tissue scanner designed for intraoperative diagnostic imaging of surgical margins, which we tested in a proof of concept study in human tissue for breast cancer diagnosis. The tissue scanner combines both diffuse reflectance spectroscopy (DRS) and intrinsic fluorescence spectroscopy (IFS), and has hyperspectral imaging capability, acquiring full DRS and IFS spectra for each scanned image pixel. Modeling of the DRS and IFS spectra yields quantitative parameters that reflect the metabolic, biochemical and morphological state of tissue, which are translated into disease diagnosis. The tissue scanner has high spatial resolution (0.25 mm) over a wide field of view (10 cm×10 cm), and both high spectral resolution (2 nm) and high spectral contrast, readily distinguishing tissues with widely varying optical properties (bone, skeletal muscle, fat and connective tissue). Tissue-simulating phantom experiments confirm that the tissue scanner can quantitatively measure spectral parameters, such as hemoglobin concentration, in a physiologically relevant range with a high degree of accuracy (<5% error). Finally, studies using human breast tissues showed that the tissue scanner can detect small foci of breast cancer in a background of normal breast tissue. This tissue scanner is simpler in design, images a larger field of view at higher resolution and provides a more physically meaningful tissue diagnosis than other spectroscopic imaging systems currently reported in literatures. We believe this spectroscopic tissue scanner can provide real-time, comprehensive diagnostic imaging of surgical margins in excised tissues, overcoming the sampling limitation in current histopathology margin assessment. As such it is a significant step in the development of a platform technology for intraoperative management of cancer, a clinical problem that has been inadequately addressed to date.

How Close Are We to Real Time Optical Margin Control in Head and Neck Oncologic Surgery?

“…This fact has prompted numerous scientific and clinical investigations regarding novel optical technology, which may allow for improved accuracy in margin detection. The field of image-guided oncologic surgery is an emerging area of research, and a variety of optical imaging modalities have been proposed during head and neck ablative oncologic surgery [16][17][18] . The development of cost-effective technology that would allow the surgeon to establish immediate, real-time margin information that is consistent with the histologic diagnosis is the ultimate objective of the field.…”

Cancer Detection in Human Tissue Samples Using a Fiber-Tip pH Probe

“…These include methodology based on Raman spectroscopy (10,11), scanning in situ spectroscopy and mapping of whole specimens (12), combined diffuse reflectance spectroscopy and intrinsic autofluorescence (10,13), or multimodal optical imaging (14). These studies have been exploratory and have examined and mapped tissue distribution in whole excised specimens ex vivo.…”

Developing an Instrument-Independent Algorithm for Raman Spectroscopy: A Case of Cancer Detection

“…Despite the potential of histopathological analysis in diagnosing the disease, it still suffers from problems such as the need for biopsy (invasion), long response time and subjective results, which highly depend on experience and expert knowledge of pathologists (3). Different techniques have been proposed for overcoming these problems among which optical techniques have recently attracted more interest due to their noninvasive and nondestructive approach (3)(4)(5)(6)(7). One of these techniques that enjoys a strong potential for detection of molecular changes and, subsequently, accurate and rapid detection of tissue lesions, is Raman spectroscopy.…”

“…One of these techniques that enjoys a strong potential for detection of molecular changes and, subsequently, accurate and rapid detection of tissue lesions, is Raman spectroscopy. Many studies have employed this technique for cancer detection (1,(7)(8)(9)(10)(11)(12).…”