Clinical | Small Animal

Ultrasound-guided percutaneous fine needle cytology moderately effective at retrieving clinically useful samples from GI lesions

vetreportFebruary 24, 2021

A recent study, published in the Journal of Small Animal Practice (JSAP), found that ultrasound-guided fine-needle cytological biopsies (FNCB) of gastrointestinal masses provided a clinically useful sample in two thirds of cases, particularly when more slides were provided and thicker lesions were sampled.

The study

The study titled “Assessment of the clinical usefulness of ultrasound-guided cytological specimens obtained from gastrointestinal lesions in dogs and cats” retrospectively analysed GI cytology samples obtained by ultrasound-guided FCNB from 25 dogs and 19 cats from the same institution between February 2014 to August 2016.

The study aimed to assess factors influencing the clinical usefulness of the GI lesion samples collected by the method of ultrasound-guided percutaneous FCNB. This method included a combination of FNI (non-aspiration) and FNA techniques, as the specific technique could not be determined retrospectively.

Clinical records of all animals were examined to collect a detailed history, clinical findings, diagnostic results and patient outcomes. Samples considered to be clinically useful were smears with sufficient cell yield and preservation to allow for at least a tentative cytological diagnosis of the lesion character or pathological process.

Factors that could have influenced the retrieval of a clinically useful sample were assessed and included lesion location, lesion thickness on ultrasound, any loss or change to the intestinal layer, and the number of sample slides submitted to the cytologists. The thickness of lesions was further categorised as either a mass (≥20 mm thickness) or a thickening (<20mm).

Dr Robert Turner, Registrar in Veterinary Radiology at the University of Melbourne and corresponding author for the paper said: “Of the submitted cytological samples, 68% (30/44) were considered clinically useful, including 11 of 18 from the stomach, eight of 12 from the small intestine, five of six from the ileocaecal junction and six of eight cases from the colon.

“The study found that both increasing lesion thickness and number of slides submitted to the cytologists were positively associated with the odds of obtaining a clinically useful sample. In a multivariable logistic regression model, some evidence was obtained that these factors were related, but the available data was insufficient to precisely estimate their combined effect.”

Nicola Di Girolamo, Editor of JSAP concluded: “The results of this study indicate that ultrasound-guided percutaneous cytology is moderately effective at retrieving clinically useful samples from GI lesions. Future research including larger, prospective studies would help to ascertain safety of this diagnostic technique, potential inter-operator variability, as well as a pragmatic comparison in terms of patient outcomes with the current standards for diagnosing GI lesions.”

The full article can be found in the February issue of the Journal of Small Animal Practice and can be read online here.

The Journal of Small Animal Practice is published monthly and access to articles is free for BSAVA members. For information on how to become a BSAVA member visit here.

Read more articles on JSAP studies here.