Identification of liver metastases with probe-based confocal laser endomicroscopy at two excitation wavelengths

TY - JOUR

T1 - Identification of liver metastases with probe-based confocal laser endomicroscopy at two excitation wavelengths

AU - Schneider, Crispin

AU - Johnson, Sean P.

AU - Gurusamy, Kurinchi

AU - Cook, Richard J.

AU - Desjardins, Adrien E.

AU - Hawkes, David J.

AU - Davidson, Brian R.

AU - Walker-Samuel, Simon

PY - 2017/3

Y1 - 2017/3

N2 - Background: Metastasis of colorectal cancer to the liver is the most common indication for hepatic resection in a western population. Incomplete excision of malignancy due to residual microscopic disease normally results in worse patient outcome. Therefore, a method aiding in the real time discrimination of normal and malignant tissue on a microscopic level would be of benefit. Material and Methods: The ability of fluorescent probe-based confocal laser endomicroscopy (pCLE) to identify normal and malignant liver tissue was evaluated in an orthotopic murine model of colorectal cancer liver metastasis (CRLM). To maximise information yield, two clinical fluorophores, fluorescein and indocyanine green (ICG) were injected and imaged in a dual wavelength approach (488 and 660nm, respectively). Visual tissue characteristics on pCLE examination were compared with histological features. Fluorescence intensity in both tissues was statistically analysed to elucidate if this can be used to differentiate between normal and malignant tissue. Results: Fluorescein (488nm) enabled good visualisation of normal and CRLM tissue, whereas ICG (660nm) visualisation was limited to normal liver tissue only. Fluorescence intensity in areas of CRLM was typically 53-100% lower than normal hepatic parenchyma. Using general linear mixed modelling and receiver operating characteristic analysis, high fluorescence intensity was found to be statistically more likely in normal hepatic tissue. Conclusion: Real time discrimination between normal liver parenchyma and metastatic tissue with pCLE examination of fluorescein and ICG is feasible. Employing two (rather than a single) fluorophores allows a combination of qualitative and quantitative characteristics to be used to distinguish between hepatic parenchyma and CRLM.

AB - Background: Metastasis of colorectal cancer to the liver is the most common indication for hepatic resection in a western population. Incomplete excision of malignancy due to residual microscopic disease normally results in worse patient outcome. Therefore, a method aiding in the real time discrimination of normal and malignant tissue on a microscopic level would be of benefit. Material and Methods: The ability of fluorescent probe-based confocal laser endomicroscopy (pCLE) to identify normal and malignant liver tissue was evaluated in an orthotopic murine model of colorectal cancer liver metastasis (CRLM). To maximise information yield, two clinical fluorophores, fluorescein and indocyanine green (ICG) were injected and imaged in a dual wavelength approach (488 and 660nm, respectively). Visual tissue characteristics on pCLE examination were compared with histological features. Fluorescence intensity in both tissues was statistically analysed to elucidate if this can be used to differentiate between normal and malignant tissue. Results: Fluorescein (488nm) enabled good visualisation of normal and CRLM tissue, whereas ICG (660nm) visualisation was limited to normal liver tissue only. Fluorescence intensity in areas of CRLM was typically 53-100% lower than normal hepatic parenchyma. Using general linear mixed modelling and receiver operating characteristic analysis, high fluorescence intensity was found to be statistically more likely in normal hepatic tissue. Conclusion: Real time discrimination between normal liver parenchyma and metastatic tissue with pCLE examination of fluorescein and ICG is feasible. Employing two (rather than a single) fluorophores allows a combination of qualitative and quantitative characteristics to be used to distinguish between hepatic parenchyma and CRLM.

KW - Confocal laser endomicroscopy

KW - Fluorescein

KW - Fluorescence microscopy

KW - Indocyanine green

KW - Liver metastases

KW - Virtual histology

UR - http://www.scopus.com/inward/record.url?scp=85007022958&partnerID=8YFLogxK

U2 - 10.1002/lsm.22617

DO - 10.1002/lsm.22617

M3 - Article

AN - SCOPUS:85007022958

SN - 0196-8092

VL - 49

SP - 280

EP - 292

JO - Lasers in Surgery and Medicine

JF - Lasers in Surgery and Medicine

IS - 3

ER -