Tumor classification by electron microscopy of fine needle aspiration biopsy material

The application of fine needle aspiration biopsy cytology to tumor diagnosis and classification is gaining increased acceptance. The classification of some poorly differentiated tumors may prove particularly difficult for the cytologist as well as for the pathologist. In such cases electron microscopic examination of fine needle aspiration biopsy material can be of great assistance. A simple, yet dependable, technique is described for the study of such material. The method has been shown to be of decisive importance in the classification of 80% of a selected series of cases submitted to ultrastructural analysis. Using this method, a preoperative diagnosis can be obtained in otherwise equivocal cases.