What does that cytology report really tell veterinarians?

Veterinary medicine is frequently about interpreting information and decision-making. Often when we read a cytology report, we base our diagnostic or treatment recommendations on the findings. When a diagnosis of malignant neoplasia is in doubt, terms expressing probability are frequently used. We have all seen the words presumptive, supportive of, can't rule out, indicative of or compatible with written on cytology reports. Do we all interpret these findings the same way?

A question of interpretation: This study explored how your colleagues interpret cytology reports when a diagnosis of malignant neoplasia is in doubt.

A survey was recently conducted that included the responses from 871 veterinarians with differing backgrounds and education. The participants were asked to give percentage probabilities of a diagnosis of lymphoma based on 18 commonly used adjective modifiers. The survey also asked the veterinarians to choose the clinical action that they would take given one of four qualified lymphoma diagnoses. When presented with the terms consistent with, probable, suggestive of or possible, the clinicians chose to either initiate treatment, perform a biopsy, consult the clinical pathologist, recheck later or recommend euthanasia if the client were considering this action if the animal had cancer.

The percentages attached to each term varied widely, with significant overlap. Interestingly, in a previous study, clinical pathologists assigned very different percentages to most of the same terms. In the current study, consistent with topped the list when it came to initiating treatment or recommending euthanasia if the client were considering it. Significant gender and experience differences were uncovered in the results. Women, general practitioners and veterinarians with less than 10 years of experience tended to assign higher percentages to the terms. Women also preferred numerical percentages to qualitative language. Even so, no one seemed to prefer being given both.

Factors affecting decision-making such as personal experiences with similar cases, clinical presentations and familiarity with a particular clinical pathologist's reports were not taken into consideration. Still, since a course of action can depend largely on the interpretation of this common vocabulary, a more standardized terminology may be needed. The comments section of any report may be the best place for clinical pathologists to further elaborate, clarify the terminology or give recommendations.

The clinical pathology terms evaluated in this study greatly affect the care of our patients, and yet they can have very different meanings to each of us. The complete results demonstrate the significant variation in interpretations and offer a thought-provoking read.

Source: Christopher MM, Hotz CS, Shelly SM, et al. Interpretation by clinicians of probability expressions in cytology reports and effect on clinical decision-making. J Vet Intern Med (2010);24(3):496-503.

Dr. Blake is a freelance technical editor and writer in Eudora, Kan.