TY - JOUR T1 - Recurrent <em>MED12</em> exon 2 mutations in benign breast fibroepithelial lesions in adolescents and young adults JF - Journal of Clinical Pathology JO - J Clin Pathol SP - 258 LP - 262 DO - 10.1136/jclinpath-2018-205570 VL - 72 IS - 3 AU - Fresia Pareja AU - Arnaud Da Cruz Paula AU - Melissa P Murray AU - Timothy Hoang AU - Rodrigo Gularte-Mérida AU - David Brown AU - Edaise M da Silva AU - Ana Paula Martins Sebastiao AU - Dilip D Giri AU - Britta Weigelt AU - Jorge S Reis-Filho AU - Edi Brogi Y1 - 2019/03/01 UR - http://jcp.bmj.com/content/72/3/258.abstract N2 - Aims Most benign breast fibroepithelial lesions (FEL) in adults harbour recurrent somatic MED12 exon 2 mutations and rare TERT promoter hotspot mutations. We sought to determine the frequency of MED12 exon 2 and TERT promoter hotspot mutations in fibroadenomas (FA) and benign phyllodes tumours (BePT) in adolescents and young adults.Methods DNA from 21 consecutive FAs and eight consecutive BePTs in adolescents and young adults was subjected to Sanger sequencing of the exon 2 of MED12 and the TERT promoter hotspot locus.Results We identified MED12 exon 2 mutations in 62% and 88% of FAs and BePTs, respectively, and no TERT promoter hotspot mutations. The majority of the MED12 exon 2 mutations identified were in-frame deletions (60%).Conclusions As in adults, benign FELs in juvenile patients harbour recurrent MED12 exon 2 mutations. ER -