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Multimodal Imaging for Cancer Margin Delineation

Posted on:2014-12-27Degree:Ph.DType:Dissertation
University:University of Massachusetts LowellCandidate:Patel, RakeshFull Text:PDF
GTID:1454390005992802Subject:Medical Imaging
Abstract/Summary:
lntraoperative delineation of cancer margins is an important problem in surgical oncology. There are very few methods available currently' for intraoperative margin delineation, so a reliable method for demarcation of benign and malignant tissue during surgery would allow for the complete resection of tumor, thus reducing cancer recurrence rate. The goal of this work was to evaluate multimodal imaging, including for delineation of breast and nonmelanoma skin cancer (NMSC) margins.;Breast cancer is the second leading cause of cancer death in women. The first step in treatment is surgical resection, which is done without intraoperative margin control. This results in re-excision rate of up to 60%. Optical modalities, including wide-field, confocal, and optical coherence tomography (OCT), can provide rapid high resolution inspection of breast tumor margins during surgery. In this work breast lumpectomy specimens were stained with methylene blue (MB), quantitative optical images were acquired and evaluated against histology. Fluorescence polarization imaging was able to accurately identify breast cancer. Averaged fluorescence polarization values of breast tumors were higher as compared to normal breast tissue. While wide-field and confocal imaging provided the lateral extent of the tumor. OCT and polarization sensitive (PS) OCT provided useful information on the cross sectional extent (depth) of cancer. Wide-field high-resolution fluorescence and fluorescence polarization imaging combined with OCT and PS OCT has potential for intraoperative delineation of breast cancers.;Nonmelanoma skin cancer (NMSC) is the most common human cancer, which rarely metastasizes, but remains the major cause of morbidity in fair-skinned population. Mohs micrographic surgery is a highly effective form of NMSC treatment, as it uses histology for intraoperative evaluation of tumor margins. However, it is also time-inefficient, labor intensive and costly. Multimodal polarization optical and terahertz imaging was evaluated as an alternative rapid, non-invasive, low cost method for assessing intrinsic contrast of cancer in NMSC samples. Optical and terahertz imaging of NMSC provided high contrast evaluation without the use of exogenous contrast agents. When used in combination with wide-field imaging, terahertz imaging highlighted the gross location of the tumor whereas the optical images accurately represented morphological features. A combination of terahertz and optical imaging of NMSC served as a first step toward multimodal evaluation of intrinsic tumor contrast.;Wide-field, confocal, OCT, and terahertz imaging modalities are capable of cancer delineation and offer complementary information. A multimodal approach has the ability to exploit the strengths of each technique to adequately address the problem of intraoperative cancer detection. A combination of these methods for margin delineation in breast and skin tissues has yielded encouraging results and will serve as a basis towards clinical applications in other tissues and cancer types.
Keywords/Search Tags:Cancer, Delineation, Imaging, Margin, Multimodal, OCT, NMSC, Breast
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