EVALUATION OF A METHOD FOR CRYOGENIC STORAGE OF CYTOLOGICAL SPECIMENS

A technique for long-term storage of cytological specimens at -70-degr ees-C was evaluated with a range of nongynaecological cytology specime ns. The effects of frozen storage on the cellularity, morphology, ultr astructure, and reactivity to cytochemical and immunochemical stains w ere investigated. These parameters were compared in preparations made from specimens processed conventionally and after frozen storage. No s ignificant deterioration in the quality of subsequent preparations was apparent after storage. The method is technically simple and has prov en successful for storing a range of specimens, including serous effus ions, urine samples, and fine-needle aspirates. This technique allows storage of material until initial microscopic evaluation is complete. If required, the relevant adjuvant procedure, such as cell blocking, m ay then be carried out using the stored material Wastage of cytologica l material on unnecessary preparations is minimised, and material may be stored over years for research or confirmation procedures. (C) 1993 Wiley-Liss, Inc.