The purpose of this study was to investigate whether B-cell clonality could be demonstrated in fine-needle aspiration (FNA)-type preparations by using automated and manual in situ hybridization (ISH) systems. FNA-like preparations were made from 10 cases of B-cell lymphoma and 5 cases of reactive lymphoid hyperplasia. Kappa/lambda expression was determined using an automated mRNA ISH assay or a manual ISH system. Other variables tested included type and length of fixation, protease digestion, and time in chromogen. Clonality data were corroborated by either flow cytometry or tissue-based analysis. Optimal conditions required formalin fixation, strong protease digestion, and prolonged hybridization and chromogen times; under these conditions, monoclonality was demonstrated by in situ in 8 of 10 cases. Each of the five cases of reactive lymphoid hyperplasia showed polyclonal light chain expression by automated mRNA ISH. In situ kappa/lambda mRNA analysis of FNA-type specimens allows direct determination of monoclonality in cytologic preparations.
|Original language||English (US)|
|Number of pages||7|
|Journal||Applied immunohistochemistry & molecular morphology : AIMM / official publication of the Society for Applied Immunohistochemistry|
|State||Published - Sep 2004|