Department of Anatomical & Cellular Pathology, The Chinese University of Hong Kong, Prince of Wales Hospital, Hong Kong

A new method of ultra-rapid histoprocessing is described which reduces the processing times for needle and endoscopic biopsies to 30 minutes and that of other surgical biopsy tissue blocks of up to 4 mm thick to 120 minutes. The MicroMED U.R.M. Histoprocessor, which combines microwave irradiation with precise computer control of power, time, temperature, vacuum, and pressure, when used with a one-step dehydrating/clearing reagent, consistently produces rapidly processed tissues with optional cytomorphology and improved tissue sectioning properties. Staining properties are excellent with no deleterious effects on routine staining, histochemistry or immunohistochemistry. This new processing technique represents a major change from conventional tissue processing and eliminates the use of hazardous reagents such as xylene. The ease of application and speed indicates that this unique technique will be a major factor in the reduction of turnaround times in diagnostic laboratories.