Intact or broken-apart RNA: an alternative concept for ALK fusion screening in non-small cell lung cancer (NSCLC).
Title | Intact or broken-apart RNA: an alternative concept for ALK fusion screening in non-small cell lung cancer (NSCLC). |
Publication Type | Journal Article |
Year of Publication | 2015 |
Authors | Kotoula, V., Bobos M., Vassilakopoulou M., Tsolaki E., Chrisafi S., Psyrri A., Lazaridis G., Papadopoulou K., Efstratiou I., Michail-Strantzia C., Debelenko L. V., Kosmidis P., & Fountzilas G. |
Journal | Appl Immunohistochem Mol Morphol |
Volume | 23 |
Issue | 1 |
Pagination | 60-70 |
Date Published | 2015 Jan |
ISSN | 1533-4058 |
Keywords | Aged, Antineoplastic Agents, Carcinoma, Non-Small-Cell Lung, Diagnostic Errors, Female, Humans, Immunohistochemistry, In Situ Hybridization, Fluorescence, Lung Neoplasms, Male, Middle Aged, Neoplasm Staging, Oncogene Proteins, Fusion, Predictive Value of Tests, Prognosis, Pyrazoles, Pyridines, Receptor Protein-Tyrosine Kinases, RNA, Messenger, Survival Analysis, Translocation, Genetic |
Abstract | Anaplastic lymphoma kinase (ALK) break-apart fluorescent in situ hybridization (FISH) is currently used in diagnostics for the selection of non-small cell lung cancer (NSCLC) patients to receive crizotinib. We evaluated ALK status in NSCLC with a novel ALK mRNA test based on the break-apart FISH concept, which we called break-apart transcript (BAT) test. ALK5' and ALK3' transcript patterns were established with qPCR for ALK-expressing controls including fusion-negative neuroblastomas, as well as fusion-positive anaplastic large cell lymphomas and NSCLC. The BAT test was evaluated on 271 RNA samples from routinely processed paraffin NSCLC tissues. Test results were compared with ALK FISH (n=121), immunohistochemical (IHC) analysis (n=86), and automated quantitative analysis (AQUA, n=83). On the basis of the nonoverlapping ALK BAT patterns in ALK-expressing controls (P<0.0001), 8/174 adenocarcinomas (4.6%) among 259 informative NSCLC were predicted as fusion positive. Overall concordance for paired method results was high (94.1% to 98.8%) but mainly concerned negative prediction because of the limited availability of positive-matched cases. Tumors with 100% cytoplasmic IHC staining of any intensity (n=3) were positive for AQUA, FISH, and BAT test; tumors with lower IHC positivity and different staining patterns were AQUA-negative. Upon multiple reevaluations, ALK gene status was considered as originally misinterpreted by FISH in 3/121 cases (2.5%). Tumors with >4 ALK gene copies were associated with longer overall survival upon first-line chemotherapy. In conclusion, application of the ALK BAT test on routinely processed NSCLC tissues yields the same fusion partner independent information as ALK break-apart FISH but is more robust and cost-effective. The BAT concept may be considered for the development of further drug-predictive translocation tests. |
DOI | 10.1097/PAI.0000000000000028 |
Alternate Journal | Appl. Immunohistochem. Mol. Morphol. |
PubMed ID | 25153496 |