Abstract
Veterinary diagnostic techniques are pivotal for the early identification and effective treatment planning, making them central to advancing veterinary oncology. They underpin the accurate identification and characterisation of neoplastic diseases, helping to guide effective treatment planning and improve animal health outcomes. This review emphasises the critical role of diverse diagnostic techniques, including cytology, histopathology, immunohistochemistry, electron microscopy, radiographic imaging (X-ray, computed tomography, positron mission tomography, magnetic resonance imaging), serology, and molecular techniques such as polymerase chain reaction (PCR), fluorescence in situ hybridization, and gene sequencing, that are critical for tumour diagnosis in veterinary practice. Despite their indispensability, these methods face significant challenges, mainly a lack of comprehensive standardisation and limited validation of established protocols and grading schemes. Recognising these related issues will assist in resolving them, which is vital for improving diagnostic accuracy, promoting innovation, and equipping veterinary professionals to make informed and effective clinical oncology decisions, thereby advancing both veterinary care and research.