Fluoroscopy-guided fine-needle aspiration of deep-seated pulmonary masses in dogs and cats appears safe and accurate.

Objective: Deep-seated pulmonary lesions can be difficult to sample safely. The objective of this study was to determine the relative safety and accuracy of fluoroscopy-guided fine-needle aspiration of deep-seated pulmonary lesions regardless of their size and depth.

Animals: Client-owned animals; 5 dogs and 5 cats.

Clinical Presentation: Pulmonary lesion locations were determined on dorsoventral and lateral views using fluoroscopy. The lateral thoracic wall was aseptically scrubbed, and an indelible marker was used to mark the point of entry of the needle for sampling. The path of a 22-gauge needle attached to a syringe was followed using fluoroscopic guidance. Mass volume (Vma) and distance from skin and pleura to lesion (DSK-L and DPL-L) were recorded.

Results: In dogs, mean Vma was 137.2 cm3 (range, 6.3 to 426.2 cm3). Mean DSK-L was 71 mm (range, 37 to 101 mm) and DPL-L was 33 mm (range, 16 to 71 mm). Exfoliative cytology results were consistent with carcinoma in 4 dogs and lymphoma in 1 dog. A minor postprocedural complication was noted in 1 dog. In cats, the mean Vma was 2.4 cm3 (range, 1.6 to 3.7 cm3). Mean DSK-L was 42 mm (range, 20 to 75 mm) and DPL-L was 21 mm (range, 12 to 32 mm). Cytology results were consistent with pulmonary carcinoma in 2 cats, inflammation in 2 cats, and necrotic debris in 1 cat.

Clinical Relevance: Fluoroscopy-guided fine-needle aspiration of pulmonary masses is a safe and accurate technique to obtain cytologic samples irrespective of the size and depth of the lesions.