Automated analysis of fluorescence in situ hybridization on fixed, paraffin-embedded whole tissue sections in B-cell lymphoma

Certain recurrent cytogenetic abnormalities are diagnostic of a specific neoplasm and may portend prognosis. As conventional cytogenetics may not reveal a neoplastic clone, and unfixed material for fluorescence in situ hybridization may be unavailable, performing fluorescence in situ hybridization on fixed tissues is diagnostically and prognostically valuable. Manual interpretation of fluorescence in situ hybridization signals may be difficult on paraffin-embedded tissue sections due to truncated nuclei. Therefore, we investigated the use of an automated image acquisition and analysis system (MetaSystems) for interpretation of fluorescence in situ hybridization signals in tissue sections from dual fusion translocation probes. Three probe sets were analyzed on archival specimens with a confirmed diagnosis of mantle cell lymphoma, follicular lymphoma or Burkitt lymphoma. 100% of mantle cell lymphomas (7/7) were positive for t(11;14), 91% of follicular lymphomas (10/11) for t(14;18) and 100% of Burkitt lymphomas (9/9) for t(8;14). Successful hybridization was achieved using various tissue fixatives and fluorescence in situ hybridization interpretation was blinded with respect to the underlying diagnosis. Based on these results, automated analysis of fluorescence in situ hybridization on fixed tissues is accurate and valuable in the evaluation of B-cell lymphoma, and may provide pertinent diagnostic and prognostic information.