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An Urban Experience
Tip #6:
Optimize the biopsy procedure itself. The use of cautery to excise tissue for biopsy should be avoided, as it creates coagulative necrosis of the sample. Punch or wedge biopsies are preferred. As a general rule, bigger biopsies provide more and better information than smaller ones. While small biopsies may sometimes be necessary (e.g., 4 mm punches are often used to sample the planum nasale), 6 or 8mm punches are preferred. New, sharp biopsy punches produce less shearing artifact than dull ones. Punches should be pressed down into the skin and twisted in a single direction until the blade pops through to the subcutaneous tissue. The sample should be carefully grasped by the subcutaneous tissue from underneath the biopsy. The dermis itself should not be grabbed or pinched, as this induces substantial artifact. The biopsy can then be gently blotted to remove excess blood and then placed in at least a 10- fold volume excess of 10% buffered formalin.
Tip #7
Provide the pathologist with as much information as possible. It can be difficult for even the most skilled pathologist to provide a meaningful interpretation from a tiny 4 or 6mm slice of skin. It can be virtually impossible when there is no context provided for the sample.
More information is always better. Provide a complete signalment for the patient, and indicate where the biopsy sample(s) were taken. A thorough history and gross description of the problem should be provided. This should include the duration of the condition, the clinical appearance, any treatment provided (and the response to that treatment), and any current medications. Differential diagnoses should be included as well. If you think that a piece of information is important for you
to know, it’s important for the pathologist to know. If possible, include photographs of the patient and the lesions.
The judicious acquisition of skin biopsies provides the clinician with a very powerful diagnostic tool. Knowledge of factors that can contribute to optimal or suboptimal samples will help the clinician maximize the likelihood
of obtaining a diagnostic specimen. Most of all, it is important to remember that the pathologist and the clinician must work together as a team for the best results. Having a thorough history, clinical description and differential list allows the pathologist to more accurately narrow down possible differentials. This can minimize the requirement for adjunctive diagnostic tests and will help the pathologist to provide the most reliable information in a timely manner.

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