Premium
MED12 exon 2 mutation as a highly sensitive and specific marker in distinguishing phyllodes tumours from other spindle neoplasms of the breast
Author(s) -
Lien HuangChun,
Huang ChiunSheng,
Yang YaWen,
Jeng YungMing
Publication year - 2016
Publication title -
apmis
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.909
H-Index - 88
eISSN - 1600-0463
pISSN - 0903-4641
DOI - 10.1111/apm.12516
Subject(s) - exon , mutation , phyllodes tumor , pathology , medicine , biology , gene , genetics
Spindle neoplasms of the breast (SNB) primarily include metaplastic breast carcinoma (MBC), phyllodes tumour (PT), fibromatosis and primary nonspecific sarcoma (PNS). Mutations in MED12 exon 2 have been reported in PTs. Because spindle tumour components are shared by SNB, we assessed the diagnostic use of MED12 exon 2 mutation in SNB. We investigated MED12 exon 2 mutations in a total of 91 samples of SNB, including 49 PT cases that have been previously analysed. Mutations were identified using direct sequencing. MED12 exon 2 mutation was absent in all cases of MBC, fibromatosis and PNS, in contrast to the 71.4% positivity in PTs. MED12 mutations were identified in four of six previously diagnosed monophasic sarcomatous MCB cases, however, these four cases were revised as malignant PT based on additional bcl‐2 staining, albeit very focal. Consistence in the MED12 mutational status between a paired core biopsy and a surgical specimen was observed in all 20 tested PT cases. In conclusion, we demonstrated the restriction of MED12 exon 2 mutation to PTs (73.6%, 39/53) and its absence in other SNB. MED12 exon 2 mutational analysis can be included in the differential diagnosis between PT and other SNB, especially with limited specimen where diagnostic clues are not evident.