Your 6-year-old cat has been to the vet 3 times in the past 2 months for a GI problem with no clear diagnosis and you feel strongly that it's time for a second opinion from a specialist. Many pet owners feel that this request will be an affront to their current trusted general vet. Just remember you are your pet's primary advocate, just as you would be for your underage child or any other person for whom you have health care guardianship. So asking your general vet for a referral to a veterinary specialist is a common-sense next step, just as it is in human medicine. Veterinary specialists work in partnership with pet owners and their vet to offer advisement, and in many instances, perform tests or procedures that are not available in a general veterinary practice.

In addition to second opinions that can be offered by veterinary specialists in internal medicine, cardiology, surgery, and ophthalmology (among others), second opinions may be sought when a biopsy is performed and test results reported. In humans with suspected cancer, second opinions on biopsies are standard practice because many studies have found the rates of discrepancies in diagnosis, and thus treatment, to be significant. In addition, studies have shown that the cost of second opinions is typically minor and can help reduce overall cost of care (eg, avoid unnecessary tests / procedures).

Although similar studies are few in veterinary medicine, results mirror those in human medicine. One study of second opinions of biopsies in 430 cats or dogs found diagnostic disagreement in 30% of cases, some disagreement in 20%, and complete disagreement in 10% of cases.

In another study, biopsies from 48 dogs and 4 cats were examined. Differences in cancer histopathology diagnoses were: 52% agreement, 29% partial disagreement, and 19% complete disagreement. The disagreements typically related to the degree of tumor malignancy, tumor type, and whether there was evidence of metastasis. Second opinions prompted changes in staging test recommendations (53%), treatment plan (100%), and prognosis (53%).

As the numbers of veterinary specialists increase, second opinions are becoming more common, and the majority of vets welcome collaboration with specialists on difficult cases. The potential benefit of a second opinion to the patient is well demonstrated in human medicine and increasingly so in veterinary medicine, not only in terms of more accurate treatment and prognosis but also in potential cost savings.

To find more information on this subject, the latest VetVine Evidence Based Update reports on the impact of second opinions in dogs and cats with cancer (veterinary professionals can earn CE credit by logging in here to register and view).

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