Method: Twelve cases of PTC and respective lymph node metastases were retrieved from our archive from 2010 to present. Formalin fixed paraffin embedded tissue sections were stained with routine hematoxilin-eosin and representative tissue areas for both tumour and metastases were microdissected and DNA was extracted. After PCR amplification the mutational status of BRAF and RAs was determined by DNA sequencing.