Frozen/Permanent discrepency article in Archives of Pathology

This article in the October '07 issue of Archives of Pathology and Laboratory Medicine, by Plesec and Prayson at the Cleveland Clinic, looks at 57 instances (out of a pool of 2156 cases) where a diagnostic discrepancy was found between frozen and later permanent sections. Of those 57, the authors were able to identify a few pitfalls that one should be aware of when attempting to make a diagnosis at frozen section.

As I read this article, I wondered about all the cases in which the pathologist wrote something so vague that a discrepancy was virtually impossible. An example of such a frozen section diagnosis might be "lesional tissue present, defer to permanents". This is sometimes a legitimate diagnosis and all the surgeon needs to know. I cannot believe that vague frozen section diagnoses like that are never rendered at the Cleveland Clinic. So, what happened to those cases in their study? Were those put in the nondescrepant category? If so, the study is only looking at cases where the neuropathologist tended to somewhat "adventuresome" in making a specific diagnosis at frozen section.

In any case, to quote the authors: "The discrepencies did not significantly impact patient management in any of the cases because postoperative management was predicated on the final diagnosis." That goes to show you how important our frozen section diagnoses are!!!

Important tips to be gleaned from this article include: 1. Perivascular hemosiderin deposition is more likely to be seen in schwannomas as opposed to meningiomas; 2. Consider CNS lymphoma when contemplating a frozen section diagnosis of small cell glioblastoma; 3. Consider sarcoma when contemplating a frozen section diagnosis of schwannoma.