Frozen sections are performed for the purpose of rapid diagnosis while a patient is undergoing surgery, usually under general anesthesia, as a basis for making immediate treatment decisions. Therefore, frozen section diagnosis is often a highly demanding situation for the pathologist who must render a diagnosis quickly and a crucial determination for the patient and surgeon. In addition to the need for rapid recall of differential diagnoses, there are many pitfalls and artifacts that add to the risk of frozen section diagnosis that are not present with permanent sections of fully processed...