Comparison of usage of indocyanine green, 5-aminolevulinic acid, methylene blue and fluorescein sodium in oncology in human and veterinary medicine

This diploma thesis investigates the use of four fluorescent dyes—indocyanine green, 5- aminolevulinic acid, methylene blue, and fluorescein sodium — in oncology veterinary medicine and compares the findings with current state in human medicine. Fluorescent dyes play a crucial role in enhancing the visualization of neoplastic tissues, aiding in the precise detection of tumors, tumor margins, metastases and lymph nodes during surgical procedures. This thesis focuses on the application of the fluorophores in dogs and cats, comparing the findings with recent studies from human medicine. A systematic review of literature from 2014 to 2024 revealed that while all four dyes are already utilized in human oncology, their application in veterinary medicine remains underexplored. Indocyanine green and methylene blue show the most promise for sentinel lymph node mapping and tumor margin delineation, nevertheless, false positive results are commonly observed with the use of indocyanine green. 5-aminolevulinic acid is notable for its greater tumor specificity, however, the existing studies are limited by small sample sizes. The current research situation on fluorescein sodium in veterinary oncology is very limited as well. The number of reported adverse effects associated with the fluorophores in dogs and cats was low. The study identifies challenges such as false-positive results due to inflammation and very small sample sizes, highlighting the urgent need for further research to optimize these techniques for the clinical use in veterinary medicine. Overall, the findings suggest that the use of fluorophores can improve surgical outcomes in veterinary oncology and reduce tumor recurrence rates. However, additional research is needed to further validate the clinical applicability and safety of these methods in dogs and cats.