Background Near-infrared fluorescence (NIRF) imaging is a relatively novel technique that can aid surgeons during intraoperative tumour identification.
Methods Nine canine oncology patients (five mammary gland tumours, three mast cell tumours and one melanoma) received intravenous indocyanine green (ICG). After 24 hours, tumours were resected and fluorescence intensities of tumours and surroundings were evaluated. Additional wound bed tissue was resected if residual fluorescence was present after tumour resection. Ex vivo, fluorescence-guided dissection was performed to separate tumour from surrounding tissue.
Results Intraoperative NIRF-guided tumour delineation was feasible in four out of nine dogs. Wound bed imaging after tumour removal identified nine additional fluorescent lesions, of which four contained tumour tissue. One of these four true positive in vivo lesions was missed by standard-of-care inspection. Ex vivo fluorescence-guided tumour dissection showed a sensitivity of 72 per cent and a specificity of 80 per cent in discriminating between tumour and surrounding tissue.
Conclusion The value of ICG for intraoperative tumour delineation seems more limited than originally thought. Although NIRF imaging using ICG did identify remaining tumour tissue in the wound bed, a high false positive rate was also observed.
- indocyanine green
- near-infrared fluorescence imaging
- tumour margin assessment
Statistics from Altmetric.com
KV and HdR contributed equally.
Funding This work was supported by the Research Foundation—Flanders (FWO; grant number 1S 00717N). Furthermore, this work was funded by Bracco Imaging SpA.
Competing interests None declared.
Ethics approval The study protocol adhered to the European Communities Council Directive (2010/63/EU). The local research ethical committee granted ethical approval for this trial (Institutional Animal Care and Use Committee; EC2015/124). Additionally, this project received approval of the deontological committee of the Federal Public Service Health, Food Chain Safety and Environment, required because of the enrolment of client-owned dogs. All owners signed an informed consent form.
Provenance and peer review Not commissioned; externally peer reviewed.
Data availability statement The authors confirm that the data supporting the findings are available within the article.
If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.