BRAF (V600E) mutation analysis on liquid‐based cytology‐processed aspiration biopsies predicts bilaterality and lymph node involvement in papillary thyroid microcarcinoma. Issue 6 (28th November 2012)

• Record Type: Journal Article
• Authors: Rossi, Esther Diana; Martini, Maurizio; Capodimonti, Sara; Lombardi, Celestino Pio; Pontecorvi, Alfredo; Vellone, Valerio Gaetano; Zannoni, Gian Franco; Larocca, Luigi Maria; Fadda, Guido
• Is Part Of: Cancer cytopathology. Volume 121:Issue 6(2013:Jun.)
• Page Start: 291
• Page End: 297
• Publication Date: 2012-11-28
• Subjects: Cancer -- Cytopathology -- Periodicals; Pathology, Cellular -- Periodicals; Cytology -- Technique -- Periodicals; 611.01815
• DOI: 10.1002/cncy.21258
• Languages: English
• ISSNs: 1934-662X

Abstract

<abstract abstract-type="main"> <title> <x xml:space="preserve">Abstract</x> </title> <sec id="cncy21258-sec-0001" sec-type="section"> <title>BACKGROUND</title> <p>Activating mutations in the valine‐to‐glutamic acid substitution at position 600 of the v‐raf murine sarcoma viral oncogene homolog B1 (<italic>BRAF‐1</italic>) gene are detected frequently in patients with papillary thyroid carcinoma (PTC). These mutations have been identified in approximately 29% to 69% of PTCs and in >80% of PTCs of the tall cell variant, whereas they have not been detected in benign lesions or in the majority of those (80%) with the follicular variant of PTC. The objective of the current study was to evaluate the role of liquid‐based cytology (LBC) for the detection of <italic>BRAF</italic> mutations in the outcome of patients who have thyroid PTC measuring ≤1 cm and, hence, in guiding their clinical and surgical management.</p> </sec> <sec id="cncy21258-sec-0002" sec-type="section"> <title>METHODS</title> <p>From October 2010 through June 2011, 230 consecutive cases were diagnosed as positive for malignancy on fine‐needle aspiration cytology processed by LBC. Of these, 73 PTCs ≤1 cm underwent <italic>BRAF</italic> mutational analysis. The aspirated material was processed using an LBC technique. After DNA extraction of the residual material, <italic>BRAF</italic> mutation analysis was performed using a direct sequencing method.</p> </sec> <sec id="cncy21258-sec-0003" sec-type="section"> <title>RESULTS</title> <p>Fifty of 73 patients (68.5%) underwent surgery, and 34 of those patients (68%) had tumors that expressed a <italic>BRAF</italic> mutation (31 PTCs, including 11 tall cell variants and 3 follicular‐variant PTCs). A significant association between <italic>BRAF</italic> mutation and bilaterality of cancer was observed (odds ratio, 0.077; <italic>P</italic> = .0007). <italic>BRAF</italic> mutation was associated significantly with lymph node involvement (odds ratio, 19; <italic>P</italic> = .0007) but not with extracapsular infiltration (odds ratio, 0.298; <italic>P</italic> = .179).</p> </sec> <sec id="cncy21258-sec-0004" sec-type="section"> <title>CONCLUSIONS</title> <p>The current results indicated that <italic>BRAF</italic> gene mutations can be identified successfully on LBC material and using other cytologic methods with high reproducibility, feasibility, and informative results. The presence of a <italic>BRAF</italic> mutation may preoperatively predict the behavior of microscopic PTC, suggesting a more aggressive surgical approach. Cancer (Cancer Cytopathol) 2013;121:291–7. © 2012 American Cancer Society.</p> </sec> </abstract>