The Usefulness of Extemporaneous Cytological Examination in Imaging-Guided Biopsies

This study investigates the usefulness of extemporaneous cytological examination per-formed during imaging-guided biopsies in dogs and cats. In veterinary diagnostics, im-aging techniques such as ultrasound and computed tomography are essential for identi-fying lesions, but they cannot distinguish between inflammatory and neoplastic process-es. Biopsies are therefore required, and this study explores whether immediate cytological evaluation of tissue cores, rolled onto slides and examined under a microscope, can help determine sample adequacy and reduce the number of biopsies needed. Seventy-nine animals with soft tissue or bone masses underwent ultrasound or CT-guided biopsies, followed by extemporaneous cytology and histopathological analysis. Cellular material representative of the lesion was identified in 81.1% of cases, allowing clinicians to con-clude the procedure without further sampling. The diagnostic accuracy of cytology com-pared to histology was 68.3%, with particularly high accuracy for lipomas, melanomas, and mast cell tumors. When excluding non-diagnostic samples due to poor preparation or lesion characteristics, accuracy reaches 93.1%. These findings suggest that extemporane-ous cytology is a useful tool for verifying sample adequacy in real time, potentially reduc-ing procedural risks and improving diagnostic efficiency. While histology remains the gold standard, this method offers immediate feedback and may enhance clinical deci-sion-making in veterinary interventional diagnostics.