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bioRxiv · 10.1101/2022.07.25.501438

Unsupervised determination of lung tumor margin with widefield polarimetric second-harmonic generation microscopy

Mirsanaye, K.·Castano, L. U.·Kamaliddin, Y.·Golaraei, A.·Kontenis, L.·Zurauskas, E.·Navab, R.·Yasufuku, K.·Tsao, M.-S.·Wilson, B. C.·Barzda, V.
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Abstract

The extracellular matrix (ECM) is amongst many tissue components affected by cancer, however, morphological changes of the ECM are not well-understood and thus, often omitted from diagnostic considerations. Polarimetric second-harmonic generation (P-SHG) microscopy allows for visualization and characterization of collagen ultrastructure in the ECM, aiding in better understanding of the changes induced by cancer throughout the tissue. In this paper, a large region of hematoxylin and eosin-stained human lung section, encompassing a tumor margin, connecting a significant tumor portion to normal tissue was imaged with P-SHG microscopy. The resulting polarimetric parameters were utilized in principal components analysis and unsupervised k-means clustering to separate normal- and tumor-like tissue. Consequently, a pseudo-color map of the clustered tissue regions is generated to highlight the irregularity of the ECM collagen structure throughout the region of interest and to identify the tumor margin.

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Mirsanaye, K., Castano, L. U., Kamaliddin, Y., Golaraei, A., Kontenis, L., Zurauskas, E., Navab, R., Yasufuku, K., Tsao, M.-S., Wilson, B. C., Barzda, V.. 2022-07-26. Unsupervised determination of lung tumor margin with widefield polarimetric second-harmonic generation microscopy. https://doi.org/10.1101/2022.07.25.501438

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