CRTC1-MAML2 fusion in mucoepidermoid carcinoma of the breast.
Histopathology
; 74(3): 463-473, 2019 Feb.
Article
en En
| MEDLINE
| ID: mdl-30380176
ABSTRACT
AIMS:
Mucoepidermoid carcinomas (MEC) are the most common malignant neoplasms of salivary glands, but are uncommon in other sites. Salivary gland MEC are most frequently associated with CRTC1-MAML2 translocations. Exceedingly rare MEC of the breast demonstrate a basal-like and often triple (oestrogen and progesterone receptor, HER2)-negative immunophenotype, with a single case previously reported to show MAML2 rearrangement, although the fusion partner was not known. Comprehensive genomic studies of breast MEC are lacking. In this study, we analysed the immunophenotype and molecular landscape of two breast MEC to elucidate the pathogenesis of these rare tumours. METHODS ANDRESULTS:
Two breast MEC were subjected to capture-based next-generation DNA sequencing of 479 cancer-related genes. The presence of the CRTC1-MAML2 fusion transcript was interrogated by reverse transcriptase-polymerase chain reaction. In addition, the immunoprofiles of breast MEC were compared to salivary gland MEC. Both breast MEC harboured CRTC1-MAML2 fusions. In contrast to most triple-negative breast carcinomas of no special type, the mutational burden of MEC was very low, with one case demonstrating only an inactivating SETD2 mutation, and the other harbouring no somatic variants in genes on the panel. No copy number alterations were identified. The immunoprofiles of breast and salivary gland MEC were overlapping, but not identical.CONCLUSIONS:
The findings highlight MEC as a breast cancer subtype more closely related to its salivary gland counterpart than to basal-like/triple-negative breast cancers of no special type.Palabras clave
Texto completo:
1
Colección:
01-internacional
Banco de datos:
MEDLINE
Asunto principal:
Factores de Transcripción
/
Neoplasias de la Mama
/
Proteínas Nucleares
/
Carcinoma Mucoepidermoide
/
Proteínas de Unión al ADN
Tipo de estudio:
Prognostic_studies
Límite:
Female
/
Humans
/
Middle aged
Idioma:
En
Revista:
Histopathology
Año:
2019
Tipo del documento:
Article
País de afiliación:
Estados Unidos