Vet360 Vet360 Vol 05 Issue 04 - Page 5

CPD ACCREDITED ARTICLE 8. The pathologist usually lacks corroborative data. 9. The clinician will believe the diagnosis is accurate and act on it. 10. The patient is still alive, so the diagnosis better be correct. The World of Veterinary Oncology Clinicians and pathologists inhabit very different parts of the oncology world and have become isolated from one another geographically as well as scientifically. Such barriers need to be broken down to achieve the best possible outcome for patients and this requires careful, timely and accurate communication among all the parties involved in the biopsy process. This breakdown in communication accounts for most of the problems, mistakes and complaints. The objective of the biopsy The objective is to obtain a sample of tissue from a living patient to identify or characterize a neoplastic process. The surgeon or clinician is involved in the decision to biopsy, the sampling of the tissue, preparation of the tissue and submission of the samples to the laboratory. The pathologist and the laboratory team continue the process, create the microscopic slides, evaluate the specimens and communicate the information back to the clinician. New and minimally invasive techniques are being applied in surgical pathology and to justify the cost of these techniques, one must maximise the diagnostic and therapeutic yields from the procedure. As a result, clinicians are wanting more useful information from each sample and with the trend toward smaller and smaller pieces of tissue, increases the pressure for an accurate diagnosis on the first samples submitted. With the cost involved with these new procedures it is unlikely that a second biopsy would be an option if the first one did not yield a useful diagnosis. Total patient evaluation Clinicians practice the principle of total patient evaluation when making judgments about diagnosis and treatment. They consider all of the data and facts at hand in reaching their conclusions. Likewise, pathologists should not base their diagnosis just on what they see on the slide. Unfortunately, in many scenarios none of the data facts are provided to the pathologists and all that they are left with is a slide to evaluate in isolation. Pathologists should describe what they see in the biopsy but make a final interpretation or diagnosis in context of all the relevant information about the case. This ability for pathologists to perform a total patient evaluation depends almost entirely on the clinician. • Total patient evaluation for pathologists: read a slide but interpret a patient. • Total patient evaluation for clinicians: give the pathologists what they need to make a patient interpretation. Outcomes of the biopsy procedure • Best outcome: rapid, accurate diagnosis of a specific neoplasia and timely application of appropriate therapy. • Worst outcome: no diagnosis made and therapy is delayed or inappropriate. • The middle route: a partial diagnosis is made but does not translate into a specific entity. The non-specific nature does not meet the clinicians expectations or the patient’s requirements. The particular outcome category depends largely on total patient evaluation information being provided pathologist. Getting a diagnostic biopsy This remains the most important task of the clinician in his workup of the tumour case. So, what constitutes a diagnostic biopsy? 1. Adequate amount of tissue. 2. Representative of the neoplastic process. 3. Sufficiently free of artefacts to permit a definitive evaluation. 4. Signalment, history, description of the lesion. 5. The clinicians differential diagnoses, rule out’s, thoughts. Adequate amount of tissu e Clinicians had a wide array of techniques at their disposable with which to obtain surgical biopsies for tumour diagnosis. Pathologists should never question first technique used by the clinician, as this is often a 1st rule of medicine (do no harm) decision. However, clinicians should be fully aware of the limitations and potential problems associated with their choice of biopsy technique. A) Fine needle aspirates • Advantage: easy, inexpensive. minimally • Use: when significant conclusions can be drawn by evaluating individual dissociated cells and is largely employed to distinguish between inflammation and neoplasia. • Disadvantage: it is extremely limited as no architectural detail can be examined. Issue 04 | SEPTEMBER 2018 | 5 invasive and