FIXATION AND STAINING OF TESTICULAR TISSUE

The aim of this study was to determine the optimal conditions for the processing and staining of specimens obtained by fine needle tissue as piration biopsy (FNTAB) of the testis. We assessed the 5 most commonly cited fixative solutions, the 6 most popular staining schedules, the effects of 6 hour and overnight dehydration and infiltration cycles, a nd 2 slide incubation temperatures. Comparisons were obtained from sou rces allocated by 5 independent observers to 7 histological features f rom 20 specimens. Sections incubated at 37 degrees C prior to staining were graded significantly higher than those incubated at 60 degrees C . Similarly, samples processed on the overnight dehydration and infilt ration cycle were found to be better preserved than those processed on the 6 hour cycle. Phosphate buffered formalin and zinc formalin were graded significantly lower than the other fixatives for all features. Scores allocated to zinc sulfate, Bouin, and Stieve solutions differed slightly. Stieve solution was selected for FNTAB because of its prove n ability to maintain the immunoreactivity of testicular tissue. The v arious staining techniques highlighted different elements of the tissu e, with the Giemsa and hematoxylin and eosin schedules providing the b est overall representations. A slight variation of the hematoxylin and eosin schedule was selected for FNTAB as it provided particularly cle ar nuclear definition.