Equipment and organization of a frozen tissue bank--an update.

The growth of molecular diagnostics and its application in various clinical laboratories has made it necessary to standardize the methods used to freeze and store tissues used in molecular testing. It may now be advantageous to preserve fresh tissues and other specimen types in a central frozen tissue bank so that sample preparation and storage conditions are appropriate for molecular applications and so that the specimen inventory can be efficiently managed. The pathology laboratory is a logical site for this facility since the professional and technical expertise available is focused on the complex scientific and managerial aspects of laboratory medicine. Organizationally, the tissue bank program should be overseen by a surgical pathologist in order to integrate it into routine surgical pathology activities. A member of the laboratory technical staff can serve as the tissue bank coordinator with responsibility for systematic storage and retrieval of specimens and routine maintenance of equipment and supplies. In order to facilitate the tissue freezing procedure as well as efficient storage of multiple types of specimens, 2.0 ml cryogenic vials are used as the uniform storage container. All specimens are stored at -140 to -150 degrees C in the vapor phase of liquid nitrogen. The specimen inventory data are maintained with a computerized program specifically designed to manage complex specimen storage. A frozen tissue bank is easily implemented in a pathology laboratory and is a valuable institutional asset for diagnostic and research purposes.