Objective: Papillary thyroid carcinoma (PTC) represents the majority of differentiated thyroid cancers, presenting the V600E activating BRAF mutation in 29-83% o f cases. The aim of our study is to analyze the influence of BRAF mutation analysis on the diagnostic accuracy of fine needle aspiration biopsy (FNAB) in patients with suspected PTC. Design and methods: Thyroid cytoaspirates from 469 nodules (size: 1.1 +/- 0.8 cm) with ultrasonographic features suspicious of malignant lesion, performed in 374 patients, were submitted to cytological evaluation and to biomolecular analysis, carried out after somatic DNA isolation, specific PCR amplification and subsequent automated direct sequencing. All PCR fragments were also processed by specific enzyme restriction analysis. Results: V600E BRAF mutation was found in 48 samples, 41 of which were also cytologically diagnosed as PTC, with histologic confirmation after thyroidectomy. Total thyroidectomy was perfomed also in 7 patients with negative cytology but positive BRAF mutation, with histological confirmation of PTC in all. Among the 429 BRAF negative samples, 407 had negative cytology for PTC, while 22 were diagnosed as suspected PTC and underwent total thyroidectomy with histological diagnosis of PTC in 17 and of benign lesion in 5. The prevalence of V600E BRAF mutation among histologically diagnosed PTC patients was 64%. Biomolecular analysis significantly increased cytology sensitivity for PTC from 77.3% to 86.7% (P<0.01). Conclusions: These data indicate that V600E BRAF mutation analysis can significantly improve FNAB diagnostic accuracy. However, biomolecular analysis is complementary to cytology, which should always be performed.
BRAF V600E mutation analysis increases diagnostic accuracy for papillary thyroid carcinoma in fine needle aspiration biopsies.
ZATELLI, Maria Chiara;TRASFORINI, Giorgio;LEONI, Stefania;FRIGATO, Gemma;Buratto M.;TAGLIATI, Federico;ROSSI, Roberta;CAVAZZINI, Luigi;ROTI, Elio;DEGLI UBERTI, Ettore
2009
Abstract
Objective: Papillary thyroid carcinoma (PTC) represents the majority of differentiated thyroid cancers, presenting the V600E activating BRAF mutation in 29-83% o f cases. The aim of our study is to analyze the influence of BRAF mutation analysis on the diagnostic accuracy of fine needle aspiration biopsy (FNAB) in patients with suspected PTC. Design and methods: Thyroid cytoaspirates from 469 nodules (size: 1.1 +/- 0.8 cm) with ultrasonographic features suspicious of malignant lesion, performed in 374 patients, were submitted to cytological evaluation and to biomolecular analysis, carried out after somatic DNA isolation, specific PCR amplification and subsequent automated direct sequencing. All PCR fragments were also processed by specific enzyme restriction analysis. Results: V600E BRAF mutation was found in 48 samples, 41 of which were also cytologically diagnosed as PTC, with histologic confirmation after thyroidectomy. Total thyroidectomy was perfomed also in 7 patients with negative cytology but positive BRAF mutation, with histological confirmation of PTC in all. Among the 429 BRAF negative samples, 407 had negative cytology for PTC, while 22 were diagnosed as suspected PTC and underwent total thyroidectomy with histological diagnosis of PTC in 17 and of benign lesion in 5. The prevalence of V600E BRAF mutation among histologically diagnosed PTC patients was 64%. Biomolecular analysis significantly increased cytology sensitivity for PTC from 77.3% to 86.7% (P<0.01). Conclusions: These data indicate that V600E BRAF mutation analysis can significantly improve FNAB diagnostic accuracy. However, biomolecular analysis is complementary to cytology, which should always be performed.I documenti in SFERA sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
