Pragmatic Algorithm for Improving the Diagnostic Quality of Fine Needle Aspiration Cytopathology in the Classification of Hematolymphoid Proliferations
Benjamin H Durham, Alaa Afify, Heidi Jess, Joo Y Song, Denis M Dwyre, Mingyi Chen. University of California, Davis, School of Medicine, Sacramento, CA
Background: Fine needle aspiration (FNA) cytopathology is a common diagnostic screening tool for suspected hematolymphoid malignancies. With an atypical lymphoid proliferation in the differential diagnosis, flow cytometric analysis is implemented. However, after preparation of the routine cytopathology smears and the cell blocks, sufficient material is sometimes unavailable for complete flow cytometric analysis. Therefore, the application of a selected panel of immunohistochemistry (IHC) with supplemental molecular studies on the FNA cell blocks can be meaningful in developing a timely and precise classification of these entities.
Design: We retrospectively reviewed the laboratory information system for FNAs performed from 2002-2012 at an academic medical center where a lymphoproliferative disorder entered into the differential diagnosis. The 240 FNAs are categorized into those that are positive for malignancy, atypical lymphoid proliferation-suspicious for malignancy, reactive, granulomatous, or nondiagnostic. A subset of 30/240 FNAs have a corresponding hematopathological tissue diagnosis and a cell block with sufficient material for additional testing. We have designed a feasible and tactical IHC diagnostic algorithmic panel (CD3, CD5, CD10, CD20, CD30, CD56, CD79a, CD138, Cyclin D1, MUM-1, and Ki-67) to classify the common hematolymphoid proliferations from cell blocks. The addition of CD56, Cyclin D1, and MUM-1 is to help differentiate a plasma cell neoplasm from a B-cell lymphoma with plasmacytic differentiation. Additionally, we use cell block molecular testing in selected cases to refine the diagnoses.
Results: Of the reviewed 240 FNA cases, 42% are positive for malignancy; 35% are atypical lymphoid proliferations-suspicious for malignancy; 19% are reactive; 1% are granulomatous; and 3% are non-diagnostic. The cell blocks of the selected subset of 30 FNA cases are evaluated by our IHC panel with the use of FISH and molecular studies in selected cases, which leads to a cell block-based classification with reasonable correlation (70%) with the corresponding tissue diagnoses.
Conclusions: Therefore, we are proposing a pragmatic diagnostic algorithm for the classification of hematolymphoid proliferations using cell blocks. Thus, use of our IHC panel and molecular studies on cell blocks can be meaningful in generating more specific diagnoses prior to the acquisition of a definitive biopsy, which is a practical approach to hematolymphoid cytopathology for improving diagnostic patient care.
Category: Quality Assurance
Tuesday, March 5, 2013 9:30 AM
Poster Session III # 286, Tuesday Morning