Investigation of optical coherence micro-elastography as a method to visualize micro-architecture in human axillary lymph nodes.
Evaluation of lymph node involvement is an important factor in detecting metastasis and deciding whether to perform axillary lymph node dissection (ALND) in breast cancer surgery. As ALND is associated with potentially severe long term morbidity, the accuracy of lymph node assessment is imperative in avoiding unnecessary ALND. The mechanical properties of malignant lymph nodes are often distinct from those of normal nodes. A method to image the micro-scale mechanical properties of lymph nodes could, thus, provide diagnostic information to aid in the assessment of lymph node involvement in metastatic cancer. In this study, we scan axillary lymph nodes, freshly excised from breast cancer patients, with optical coherence micro-elastography (OCME), a method of imaging micro-scale mechanical strain, to assess its potential for the intraoperative assessment of lymph node involvement.



Twenty-six fresh, unstained lymph nodes were imaged from 15 patients undergoing mastectomy or breast-conserving surgery with axillary clearance. Lymph node specimens were bisected to allow imaging of the internal face of each node. Co-located OCME and optical coherence tomography (OCT) scans were taken of each sample, and the results compared to standard post-operative hematoxylin-and-eosin-stained histology.



The optical backscattering signal provided by OCT alone may not provide reliable differentiation by inspection between benign and malignant lymphoid tissue. Alternatively, OCME highlights local changes in tissue strain that correspond to malignancy and are distinct from strain patterns in benign lymphoid tissue. The mechanical contrast provided by OCME complements the optical contrast provided by OCT and aids in the differentiation of malignant tumor from uninvolved lymphoid tissue.



The combination of OCME and OCT images represents a promising method for the identification of malignant lymphoid tissue. This method shows potential to provide intraoperative assessment of lymph node involvement, thus, preventing unnecessary removal of uninvolved tissues and improving patient outcomes.
Optical+Biomedical Engineering Laboratory, School of Electrical, Electronic & Computer Engineering, The University of Western Australia, 35 Stirling Highway, Perth, WA, 6009, Australia.
Kelsey M
KM
Kennedy
Optical+Biomedical Engineering Laboratory, School of Electrical, Electronic & Computer Engineering, The University of Western Australia, 35 Stirling Highway, Perth, WA, 6009, Australia. lixin.chin@research.uwa.edu.au.|BRITElab, Harry Perkins Institute of Medical Research, QEII Medical Centre, 6 Verdun St, Nedlands, Perth, WA, 6009, Australia. lixin.chin@research.uwa.edu.au.
Lixin
L
Chin
Optical+Biomedical Engineering Laboratory, School of Electrical, Electronic & Computer Engineering, The University of Western Australia, 35 Stirling Highway, Perth, WA, 6009, Australia.|BRITElab, Harry Perkins Institute of Medical Research, QEII Medical Centre, 6 Verdun St, Nedlands, Perth, WA, 6009, Australia.
Philip
P
Wijesinghe
Optical+Biomedical Engineering Laboratory, School of Electrical, Electronic & Computer Engineering, The University of Western Australia, 35 Stirling Highway, Perth, WA, 6009, Australia.|Australian Research Council Centre of Excellence for Nanoscale BioPhotonics, School of Medicine, Faculty of Health Sciences, University of Adelaide, Adelaide, SA, 5005, Australia.
Robert A
RA
McLaughlin
PathWest, Fiona Stanley Hospital, Robin Warren Drive, Murdoch, WA, 6150, Australia.
Bruce
B
Latham
Optical+Biomedical Engineering Laboratory, School of Electrical, Electronic & Computer Engineering, The University of Western Australia, 35 Stirling Highway, Perth, WA, 6009, Australia.|Centre for Microscopy, Characterisation & Analysis, The University of Western Australia, 35 Stirling Highway, Perth, WA, 6009, Australia.
David D
DD
Sampson
School of Surgery, The University of Western Australia, 35 Stirling Highway, Perth, WA, 6009, Australia.|Breast Clinic, Royal Perth Hospital, 197 Wellington Street, Perth, WA, 6000, Australia.
Christobel M
CM
Saunders
Optical+Biomedical Engineering Laboratory, School of Electrical, Electronic & Computer Engineering, The University of Western Australia, 35 Stirling Highway, Perth, WA, 6009, Australia.|BRITElab, Harry Perkins Institute of Medical Research, QEII Medical Centre, 6 Verdun St, Nedlands, Perth, WA, 6009, Australia.
Brendan F
BF
Kennedy
D001365:Axilla; D001943:Breast Neoplasms / Q000000981:diagnostic imaging* / Q000601:surgery; D054459:Elasticity Imaging Techniques / Q000379:methods*; D005260:Female; D006801:Humans; D007430:Intraoperative Care; D008198:Lymph Nodes / Q000000981:diagnostic imaging* / Q000601:surgery; D008207:Lymphatic Metastasis; D064847:Multimodal Imaging; D041623:Tomography, Optical Coherence / Q000379:methods*
Breast cancer; Elastography; Intraoperative; Lymph node; Mechanical properties; Optical coherence tomography