Technical ArticlesSimultaneous Phenotyping and Genotyping (FICTION-Methodology) on Paraffin Sections and Cytologic Specimens: A Comparison of 2 Different ProtocolsBzorek, Michael Sr MT*; Petersen, Bodil Laub MD, PhD†; Hansen, Linda MT*Author Information *Department of Pathology, Storstrømmens Hospital, Naestved †Department of Pathology, National Hospital, Denmark Reprints: Michael Bzorek, Sr, MT, Department of Pathology, Storstrømmens Hospital in Naestved, Ringstedgade 61, 4700 Naestved, Denmark (e-mail: firstname.lastname@example.org). Received for publication January 30, 2007; accepted May 8, 2007 Applied Immunohistochemistry & Molecular Morphology: May 2008 - Volume 16 - Issue 3 - p 279-286 doi: 10.1097/PAI.0b013e3180de490f Buy Metrics Abstract Combining immunofluorescence labeling with fluorescence in situ hybridization (FISH) is a powerful technique simultaneously studying immunophetypic markers and genetic abnormalities present in tumor cells [the FICTION method (fluorescence immunophenotyping, and interphase cytogenetics as a tool for the investigation of neoplasms)]. However, few studies have been applied to the technical problems posed by antigen retrieval and accessibility of genetic probes to target-DNA, using formalin-fixed, paraffin-embedded tissue. In this study, we compared 2 immunofluorescence detection systems, the 3-step IF (TIF) method against the Tyramide Signal Amplification techniques (TSA). The FICTION-TSA technique significantly improved the sensitivity for detection of the immunophenotypic markers without influencing specific probe hybridization to target-DNA, compared with the results obtained with the TIF method. The reaction product of the TSA system was robust to the following FISH procedure in contrast to the TIF technique. The TSA technique used also allowed synchronous detection of nuclear antigens and FISH signals using both fusion (IgH/CCND1) and break-apart (CCND1) probes on formalin-fixed paraffin-embedded tissue. © 2008 Lippincott Williams & Wilkins, Inc.