Premium
Fusion gene profile of biphenotypic sinonasal sarcoma: an analysis of 44 cases
Author(s) -
Fritchie Karen J,
Jin Long,
Wang Xiaoke,
Graham Rondell P,
Torbenson Michael S,
Lewis Jean E,
Rivera Michael,
Garcia Joaquin J,
SchembriWismayer David J,
Westendorf Jennifer J,
Chou Margaret M,
Dong Jie,
Oliveira Andre M
Publication year - 2016
Publication title -
histopathology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.626
H-Index - 124
eISSN - 1365-2559
pISSN - 0309-0167
DOI - 10.1111/his.13045
Subject(s) - pax3 , fusion gene , biology , sarcoma , gene , fusion transcript , pathology , medicine , genetics , transcription factor
Aims Biphenotypic sinonasal sarcoma ( SNS ) is a locally aggressive tumour that occurs in the sinonasal region. PAX 3 – MAML 3 has recently been identified as a recurrent fusion gene event in this entity; however, a subset of tumours harbour alternative PAX 3 rearrangement without the involvement of MAML 3 . In this study we sought to characterize the molecular profile of a large series of cases, with a special emphasis on tumours with alternative fusions. Methods and results Forty‐four examples of SNS were screened by fluorescence in‐situ hybridization and reverse transcription polymerase chain reaction to better characterize its molecular profile and identify potential novel fusion genes. Twenty‐four were positive for PAX 3– MAML 3 (55%), 15 showed rearrangements of PAX 3 without MAML 3 involvement (34%), one showed rearrangement of MAML 3 without PAX 3 involvement, and four were negative for the involvement of either gene (9%). Among 15 cases with PAX 3 involvement only, three were found to harbour PAX 3– FOXO 1 . Two of these cases arose in the nasal cavities of female patients (aged 31 and 47 years), and one showed bilateral involvement of the nasal cavities of a 35‐year‐old male. A fourth case involved the skull base of a 47‐year‐old male, and was positive for PAX 3– NCOA 1 . Patients with fusion‐negative tumours were slightly older. Conclusion More than half of the SNS s in this series were positive for PAX 3– MAML 3 . However, a subset of tumours may harbour alternative PAX 3 fusion genes or show no involvement of PAX 3 . Except for a possible weak association between age and molecular profile, the overall morphological and immunophenotypic features of all cases seem to be similar. Because of the rarity of these tumours, the impact of the molecular profile on the clinical course of these tumours remains to be determined.