Microwave assisted irradiation in tissue preparation: From fixation to staining as an alternative approach in histopathology laboratories

Fixation, which is the first step in tissue preparation in histopathology laboratories, followed
by tissue processing, embedding and staining. Routine use of formalin fixation, dehydration,
paraffin infiltration, embedding and sectioning gives uniform and well preserved tissue
structure closest to the live one. These routine procedures take at least 1 to 4 days, depending
on the technique used. In this study it is aimed to assess microwave assisted irradiation in tissue
fixation, processing and staining and to determine if it can be replaced routine formalin fixed
paraffin embedded tissue preparation. For this purpose, liver and kidney pieces taken from rats
were fixed with microwave irradiation. After fixation; tissue dehydration, clearing (1,1,1
trichloroethane), impregnation and staining steps were all performed in the microwave oven.
When the results were compared with the standard protocol there was no statistically significant
difference in terms of morphology as structural preservation and staining quality. All tissue
preparations carried out in microwave oven were completed in 2 hours and 10 minutes. Because
of the ease of application and speed of the technique; this microwave assisted tissue preparation
technique can be used as an alternate in histopathology laboratories for rapid diagnosis. For
example formaline fixed parafine embedded tissues stored for longer period had a reduced
concentration and quantity of extractable protein, RNA and DNA. Especially in precision
oncology for detecting somatic variations; it can be speculated that our microwave assisted
tissue preparation can be an alternative method for better quality of protein, RNA and DNA.
To show this; an experiment will be planned for future directions.