Fine needle aspiration, often abbreviated FNA, is one of the most powerful yet underappreciated tools in veterinary medicine. The technique involves inserting a thin needle into a mass and drawing out cells, which are then smeared onto a slide, stained, and examined under a microscope. Compared with surgical biopsy, it is minimally invasive, carries low risk, costs far less, and can produce results within minutes to days. When a dog or cat presents with a persistent lump measuring at least one centimeter, roughly the size of a pea, that has been present for a month or longer, established guidelines from the American Animal Hospital Association recommend FNA or biopsy to obtain a diagnosis before any treatment decisions are made. The rationale is straightforward: knowing whether a mass is benign or malignant, and what type of tumor it might be, fundamentally changes how a veterinarian plans surgery, staging, and follow-up care.

The stakes are considerable. Roughly 30 percent of all tumors in dogs and cats arise in the skin or the tissue just beneath it, and malignancy rates in these lesions vary dramatically between species. In dogs, an estimated 20 to 40 percent of skin tumors are malignant; in cats, the figure climbs to between 70 and 82 percent. Because a lump that feels benign to the examining hand may in fact be an aggressive cancer, the guidelines emphasize that no definitive diagnosis can ever be made on palpation alone. Yet the new survey suggests that in everyday practice, clinical impression frequently wins out over cytology.

The research team, led by Gillian Dank of Onco Pet Veterinary Services in Israel along with colleagues at HT Vet and in private consulting, distributed a 16-question survey by email to 10,000 small-animal veterinary professionals across the United States, including veterinarians, veterinary technicians, and practice managers. A total of 240 respondents completed the questionnaire, a response rate of 2.4 percent, with 235 providing fully answered forms. Most respondents were veterinarians, about 62 percent of practices were independently owned, and the vast majority worked in general practice. The survey asked about daily caseloads of mass patients, the proportion of cases in which FNA was performed, whether samples were evaluated in-house or sent to reference laboratories, the perceived rate of inconclusive results, and the barriers that discouraged the test.

The statistical analysis, conducted in Python using standard tests of association, revealed several striking patterns. Clinicians who evaluated four or more patients with dermal or subcutaneous masses per day were significantly less likely to perform FNA than those seeing fewer than four such patients daily, a difference that reached statistical significance. The mean FNA rate fell from roughly 41 to 42 percent among lower-volume respondents to 33 percent among those with the heaviest caseloads. The authors suggest that the cumulative cognitive load of making dozens of clinical decisions each day may push busy veterinarians toward a quick wait-and-see discharge rather than an additional procedure, particularly when a lump is an incidental finding during a visit for something else.

Experience, surprisingly, worked in the opposite direction. Clinicians with more than 20 years in practice were significantly over-represented among the high users of FNA, performing the test on more than half of masses at rates of 40 to 44 percent, compared with only 19 to 24 percent among less experienced colleagues. This contradicts the intuitive assumption that seasoned veterinarians feel comfortable judging a lump by look and feel alone. The authors speculate that decades of practice bring greater familiarity with the aspiration technique and a deeper appreciation of its clinical utility, gained through years of watching palpation-based guesses go wrong.

The barriers veterinarians cited for skipping the test were revealing. The most common primary reason, selected by 35 percent of respondents, was the perception that the mass was benign and did not require further investigation. Cost concerns came second at 32 percent, and client declination for reasons other than cost accounted for 19 percent. Taken together, the cost and refusal categories suggest that in roughly half of cases, the veterinarian would have performed the aspiration if the owner had agreed. Only 8 percent cited limited confidence in the diagnostic value of FNA itself, and just 4 percent pointed to the time the procedure takes. Notably, when the same respondents were asked what percentage of lumps could be accurately diagnosed from palpation and history alone, half estimated that this was reliable in fewer than 10 percent of cases, a striking contradiction with their stated reliance on clinical impression. The authors interpret this as a gap between theoretical knowledge and the practical, split-second decision-making of a busy appointment.

One of the most consequential findings concerned surgery. Respondents reported performing excisional biopsies, in which the entire mass is surgically removed, without any prior FNA in an average of 30 percent of cases. Clinicians who expressed confidence in diagnosing lumps by palpation alone were two and a half times more likely to skip the preoperative aspiration. This matters because knowing the tumor type before surgery provides critical information about local invasiveness, metastatic potential, and whether the cancer spreads through lymphatic or blood vessels, all of which influence the width of surgical margins, the need for preoperative staging tests, and the overall surgical strategy. Since the first operation often offers the best chance of complete tumor removal, proceeding blind may, in some cases, compromise the outcome. The authors caution, however, that there are legitimate reasons to excise directly, such as very small masses that appear benign, or palliative procedures where tumor typing would not change the plan.

The survey also examined the role of digital cytology, a rapidly growing technology that allows slide images to be transmitted to remote board-certified clinical pathologists for interpretation. About 35 percent of clinics reported using such services, with medium and large practices significantly more likely to adopt them than small ones. Counterintuitively, clinics with digital cytology performed fewer aspirations overall, 35 percent versus 42 percent, evaluated fewer samples in-house, and reported higher rates of inconclusive results. The authors offer several possible explanations: clinicians may expect definitive answers from submitted samples and grow frustrated when findings are non-diagnostic; the higher cost of digital services may discourage routine use; slide preparation and upload take time during busy consultations; or the association may simply be confounded by the fact that larger, high-volume clinics, which already perform fewer aspirations, are also the ones most likely to have the technology.

The study has limitations that the authors acknowledge candidly. The response rate was low, the survey reached only US-based subscribers of a single professional publication, and many answers relied on recollection rather than verified clinical records. The questionnaire also did not capture the clinical reasoning behind every decision to skip aspiration. Even so, the overall picture is consistent: a fast, cheap, minimally invasive test that veterinary schools teach and guidelines endorse is being underused, especially where caseload pressure is highest. The authors argue that better integration of FNA into routine workflows, along with hands-on training for veterinary students and practicing clinicians in both aspiration technique and slide assessment, could close the gap between what the guidelines recommend and what actually happens when a worried owner points to a lump on their pet. Early diagnosis, they emphasize, remains one of the most powerful predictors of a good outcome in veterinary oncology, and the pea-sized lump dismissed today may be the aggressive tumor that a two-minute needle test could have caught in time.

Subject of Research: Underuse of fine needle aspiration for diagnosing skin masses in dogs and cats in veterinary practice

Article Title: Underutilization of fine needle aspiration for canine and feline superficial masses-survey results

Article References: Dank, G., Buber, T., Levy-Hirsch, L., Fink, A., Marks, N., Greenberg, U., & Hanael, E. (2026). Underutilization of fine needle aspiration for canine and feline superficial masses-survey results. Veterinary Oncology, 3(1), Article 25. https://doi.org/10.1186/s44356-026-00077-0

Image Credits: AI Generated

DOI: 10.1186/s44356-026-00077-0

Keywords: fine needle aspiration, veterinary oncology, cytology, dogs, cats, skin masses, biopsy, digital cytology, diagnostic guidelines, survey research, cancer diagnosis, veterinary practice