Histopathology. 2018 Apr 4. doi: 10.1111/his.13526. [Epub ahead of print]
Pseudosarcomatous Myofibroblastic Proliferations of the Genitourinary Tract are Genetically Different from Nodular Fasciitis and Lack USP6, ROS1, and ETV6 Gene Rearrangements.
Jebastin JA, Smith SC, Perry KD, Gupta NS, Alanee S, Carskadon S, Chitale DA, Palanisamy N, Williamson SR.
AIMS:
Pseudosarcomatous myofibroblastic proliferations of the genitourinary tract have a debatable relationship to inflammatory myofibroblastic tumour (generally lacking ALK rearrangement); however, they share several overlapping features with nodular fasciitis of soft tissue. Since rearrangement of the USP6 gene has been recently recognized as a recurrent alteration in soft tissue nodular fasciitis, and several other alternative gene fusions have been recently recognized in inflammatory myofibroblastic tumour, we studied whether USP6, ROS1, or ETV6 gene rearrangements were present in these lesions (12 cases).
METHODS AND RESULTS:
Fluorescence in-situ hybridization (FISH) analysis was performed using bacterial artificial chromosome (BAC) derived break-apart probes against USP6, ROS1, and ETV6. Two cases with adequate genetic material from recent paraffin tissue blocks were also tested by using a solid tumour gene fusion detection assay via next-generation sequencing, targeting over 50 known genes involved in recurrent fusions. None of the genitourinary pseudosarcomatous myofibroblastic proliferations was detected to harbour USP6 (0/12), ROS1 (0/8), or ETV6 (0/7) rearrangement and no gene fusions were detected in 2 cases studied by sequencing.
CONCLUSIONS:
Despite overlap in histologic and immunohistochemical features between pseudosarcomatous myofibroblastic proliferation and nodular fasciitis, these tumours lack the recently recognized USP6 gene rearrangements that occur in nodular fasciitis, as well as alternative fusions found in ALK-negative inflammatory myofibroblastic tumours. At present, this diagnosis remains based primarily on clinical, histologic, and immunohistochemical features. This article is protected by copyright. All rights reserved.
This article is protected by copyright. All rights reserved.
KEYWORDS:
USP6; inflammatory myofibroblastic tumour; pseudosarcomatous myofibroblastic proliferation; soft tissue tumours; urinary bladder
PMID: 29617048 DOI: 10.1111/his.13526
Pseudosarcomatous Myofibroblastic Proliferations of the Genitourinary Tract are Genetically Different from Nodular Fasciitis and Lack USP6, ROS1, and ETV6 Gene Rearrangements.
Jebastin JA, Smith SC, Perry KD, Gupta NS, Alanee S, Carskadon S, Chitale DA, Palanisamy N, Williamson SR.
AIMS:
Pseudosarcomatous myofibroblastic proliferations of the genitourinary tract have a debatable relationship to inflammatory myofibroblastic tumour (generally lacking ALK rearrangement); however, they share several overlapping features with nodular fasciitis of soft tissue. Since rearrangement of the USP6 gene has been recently recognized as a recurrent alteration in soft tissue nodular fasciitis, and several other alternative gene fusions have been recently recognized in inflammatory myofibroblastic tumour, we studied whether USP6, ROS1, or ETV6 gene rearrangements were present in these lesions (12 cases).
METHODS AND RESULTS:
Fluorescence in-situ hybridization (FISH) analysis was performed using bacterial artificial chromosome (BAC) derived break-apart probes against USP6, ROS1, and ETV6. Two cases with adequate genetic material from recent paraffin tissue blocks were also tested by using a solid tumour gene fusion detection assay via next-generation sequencing, targeting over 50 known genes involved in recurrent fusions. None of the genitourinary pseudosarcomatous myofibroblastic proliferations was detected to harbour USP6 (0/12), ROS1 (0/8), or ETV6 (0/7) rearrangement and no gene fusions were detected in 2 cases studied by sequencing.
CONCLUSIONS:
Despite overlap in histologic and immunohistochemical features between pseudosarcomatous myofibroblastic proliferation and nodular fasciitis, these tumours lack the recently recognized USP6 gene rearrangements that occur in nodular fasciitis, as well as alternative fusions found in ALK-negative inflammatory myofibroblastic tumours. At present, this diagnosis remains based primarily on clinical, histologic, and immunohistochemical features. This article is protected by copyright. All rights reserved.
This article is protected by copyright. All rights reserved.
KEYWORDS:
USP6; inflammatory myofibroblastic tumour; pseudosarcomatous myofibroblastic proliferation; soft tissue tumours; urinary bladder
PMID: 29617048 DOI: 10.1111/his.13526
