Premium
Diagnosis of anaplastic lymphoma kinase rearrangement in cytological samples through a fluorescence in situ hybridization–based assay: Cytological smears versus cell blocks
Author(s) -
Zito Marino Federica,
Rossi Giulio,
Brunelli Matteo,
Malzone Maria Gabriella,
Liguori Giuseppina,
Bogina Giuseppe,
Morabito Alessandro,
Rocco Gaetano,
Franco Renato,
Botti Gerardo
Publication year - 2017
Publication title -
cancer cytopathology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.29
H-Index - 57
eISSN - 1934-6638
pISSN - 1934-662X
DOI - 10.1002/cncy.21835
Subject(s) - medicine , fluorescence in situ hybridization , anaplastic lymphoma kinase , in situ , pathology , lymphoma , in situ hybridization , fluorescence , biology , chemistry , biochemistry , gene , malignant pleural effusion , chromosome , lung cancer , gene expression , physics , organic chemistry , quantum mechanics
Anaplastic lymphoma kinase (ALK) status analysis of lung cytological specimens should be successfully encouraged in routine practice because biopsy specimens are not always available. To date, the US Food and Drug Administration has approved both fluorescence in situ hybridization (FISH) and immunohistochemistry (IHC) as diagnostic tests for identifying ALK‐positive patients eligible for treatment with crizotinib. Although ALK IHC is an optimal diagnostic tool, FISH becomes mandatory in equivocal cases. ALK FISH of paraffin‐embedded tissue material is still the gold standard, whereas the cytological specimen assay has not yet been completely standardized. Many controversial data have been reported on the adequacy of cytology cell blocks (CBs) versus conventional smears for FISH testing. This review discusses some critical issues related to ALK FISH of cytological samples, including the triaging of collected specimens to optimize the material, the use of CBs versus conventional smears, and alternative methods for an ALK rearrangement diagnosis. Conventional smears have the advantages of an immediate evaluation, no probe tissue‐related artifactual loss, no fixation‐related alterations, and usually sufficient material for an analytic preparation. On the other hand, CBs have several advantages, including the appropriate conservation of the tissue architecture, an absence of problems related to cell overlapping, and the ability to evaluate neoplastic cells in a dark field. Cancer Cytopathol 2017;125:303–312. © 2017 American Cancer Society.