The implications of abnormal signal patterns of break-apart FISH probes used in the diagnosis of bone and soft tissue tumours

Many subtypes of bone and soft tissue tumours harbour specific chromosome translocations leading to chimeric fusion genes. The identification of these specific fusion genes is the basis of molecular diagnoses in such tumours. Break-apart FISH is a robust method that is commonly used to identify thes...

Full description

Saved in:
Bibliographic Details
Main Authors: Hongtao Ye, Fitim Berisha, Evie Rowles, Emani Munasinghe, Christopher Davies, Akanksha Farswan, Nischalan Pillay
Format: Article
Language:English
Published: Frontiers Media S.A. 2025-07-01
Series:Pathology and Oncology Research
Subjects:
Online Access:https://www.por-journal.com/articles/10.3389/pore.2025.1612142/full
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1850107008473104384
author Hongtao Ye
Fitim Berisha
Evie Rowles
Emani Munasinghe
Christopher Davies
Akanksha Farswan
Nischalan Pillay
Nischalan Pillay
author_facet Hongtao Ye
Fitim Berisha
Evie Rowles
Emani Munasinghe
Christopher Davies
Akanksha Farswan
Nischalan Pillay
Nischalan Pillay
author_sort Hongtao Ye
collection DOAJ
description Many subtypes of bone and soft tissue tumours harbour specific chromosome translocations leading to chimeric fusion genes. The identification of these specific fusion genes is the basis of molecular diagnoses in such tumours. Break-apart FISH is a robust method that is commonly used to identify these translocations and provide diagnostic support to histological interpretations. The signal patterns of the break-apart probes are usually easily interpreted. However, some cases show abnormal signal patterns leading to equivocal and challenging interpretation. The incidence of these abnormal patterns is largely unknown. Using a retrospective cohort we explored the incidence of abnormal signal patterns across common bone and soft tissue tumour types to raise awareness of this occurrence and to aid in the interpretation. In total, 1,087 bone and soft tissue tumours tested by break-apart probes were examined. The abnormal signal patterns were classified as deletion, additional copy and amplification, which were found at highest frequency in low-grade fibromyxoid sarcoma (32%, 6/19), and at moderate frequencies in those from alveolar rhabdomyosarcoma (10%, 9/94), nodular fasciitis (9%, 18/209), synovial sarcoma (8%, 17/207) and Ewing sarcoma/round cell sarcoma with EWSR1-non-ETS fusions (6%, 29/497). The lowest frequency was found in clear cell sarcoma (1%, 1/61). Despite the equivocal results from the abnormal signal patterns, the specific fusion genes were confirmed by orthogonal molecular techniques such as FISH with fusion probes, RT-PCR or next-generation sequencing.
format Article
id doaj-art-40b7017d9bda479c8c452b23cb9fcf10
institution OA Journals
issn 1532-2807
language English
publishDate 2025-07-01
publisher Frontiers Media S.A.
record_format Article
series Pathology and Oncology Research
spelling doaj-art-40b7017d9bda479c8c452b23cb9fcf102025-08-20T02:38:41ZengFrontiers Media S.A.Pathology and Oncology Research1532-28072025-07-013110.3389/pore.2025.16121421612142The implications of abnormal signal patterns of break-apart FISH probes used in the diagnosis of bone and soft tissue tumoursHongtao Ye0Fitim Berisha1Evie Rowles2Emani Munasinghe3Christopher Davies4Akanksha Farswan5Nischalan Pillay6Nischalan Pillay7Department of Cellular and Molecular Pathology, Royal National Orthopaedic Hospital, Stanmore, United KingdomDepartment of Cellular and Molecular Pathology, Royal National Orthopaedic Hospital, Stanmore, United KingdomDepartment of Cellular and Molecular Pathology, Royal National Orthopaedic Hospital, Stanmore, United KingdomDepartment of Cellular and Molecular Pathology, Royal National Orthopaedic Hospital, Stanmore, United KingdomCancer Institute, University College London, London, United KingdomCancer Institute, University College London, London, United KingdomDepartment of Cellular and Molecular Pathology, Royal National Orthopaedic Hospital, Stanmore, United KingdomCancer Institute, University College London, London, United KingdomMany subtypes of bone and soft tissue tumours harbour specific chromosome translocations leading to chimeric fusion genes. The identification of these specific fusion genes is the basis of molecular diagnoses in such tumours. Break-apart FISH is a robust method that is commonly used to identify these translocations and provide diagnostic support to histological interpretations. The signal patterns of the break-apart probes are usually easily interpreted. However, some cases show abnormal signal patterns leading to equivocal and challenging interpretation. The incidence of these abnormal patterns is largely unknown. Using a retrospective cohort we explored the incidence of abnormal signal patterns across common bone and soft tissue tumour types to raise awareness of this occurrence and to aid in the interpretation. In total, 1,087 bone and soft tissue tumours tested by break-apart probes were examined. The abnormal signal patterns were classified as deletion, additional copy and amplification, which were found at highest frequency in low-grade fibromyxoid sarcoma (32%, 6/19), and at moderate frequencies in those from alveolar rhabdomyosarcoma (10%, 9/94), nodular fasciitis (9%, 18/209), synovial sarcoma (8%, 17/207) and Ewing sarcoma/round cell sarcoma with EWSR1-non-ETS fusions (6%, 29/497). The lowest frequency was found in clear cell sarcoma (1%, 1/61). Despite the equivocal results from the abnormal signal patterns, the specific fusion genes were confirmed by orthogonal molecular techniques such as FISH with fusion probes, RT-PCR or next-generation sequencing.https://www.por-journal.com/articles/10.3389/pore.2025.1612142/fullFISHabnormal signal patternbreak-apart probebone and soft tissue tumourgene rearrangementtranslocation
spellingShingle Hongtao Ye
Fitim Berisha
Evie Rowles
Emani Munasinghe
Christopher Davies
Akanksha Farswan
Nischalan Pillay
Nischalan Pillay
The implications of abnormal signal patterns of break-apart FISH probes used in the diagnosis of bone and soft tissue tumours
Pathology and Oncology Research
FISH
abnormal signal pattern
break-apart probe
bone and soft tissue tumour
gene rearrangement
translocation
title The implications of abnormal signal patterns of break-apart FISH probes used in the diagnosis of bone and soft tissue tumours
title_full The implications of abnormal signal patterns of break-apart FISH probes used in the diagnosis of bone and soft tissue tumours
title_fullStr The implications of abnormal signal patterns of break-apart FISH probes used in the diagnosis of bone and soft tissue tumours
title_full_unstemmed The implications of abnormal signal patterns of break-apart FISH probes used in the diagnosis of bone and soft tissue tumours
title_short The implications of abnormal signal patterns of break-apart FISH probes used in the diagnosis of bone and soft tissue tumours
title_sort implications of abnormal signal patterns of break apart fish probes used in the diagnosis of bone and soft tissue tumours
topic FISH
abnormal signal pattern
break-apart probe
bone and soft tissue tumour
gene rearrangement
translocation
url https://www.por-journal.com/articles/10.3389/pore.2025.1612142/full
work_keys_str_mv AT hongtaoye theimplicationsofabnormalsignalpatternsofbreakapartfishprobesusedinthediagnosisofboneandsofttissuetumours
AT fitimberisha theimplicationsofabnormalsignalpatternsofbreakapartfishprobesusedinthediagnosisofboneandsofttissuetumours
AT evierowles theimplicationsofabnormalsignalpatternsofbreakapartfishprobesusedinthediagnosisofboneandsofttissuetumours
AT emanimunasinghe theimplicationsofabnormalsignalpatternsofbreakapartfishprobesusedinthediagnosisofboneandsofttissuetumours
AT christopherdavies theimplicationsofabnormalsignalpatternsofbreakapartfishprobesusedinthediagnosisofboneandsofttissuetumours
AT akankshafarswan theimplicationsofabnormalsignalpatternsofbreakapartfishprobesusedinthediagnosisofboneandsofttissuetumours
AT nischalanpillay theimplicationsofabnormalsignalpatternsofbreakapartfishprobesusedinthediagnosisofboneandsofttissuetumours
AT nischalanpillay theimplicationsofabnormalsignalpatternsofbreakapartfishprobesusedinthediagnosisofboneandsofttissuetumours
AT hongtaoye implicationsofabnormalsignalpatternsofbreakapartfishprobesusedinthediagnosisofboneandsofttissuetumours
AT fitimberisha implicationsofabnormalsignalpatternsofbreakapartfishprobesusedinthediagnosisofboneandsofttissuetumours
AT evierowles implicationsofabnormalsignalpatternsofbreakapartfishprobesusedinthediagnosisofboneandsofttissuetumours
AT emanimunasinghe implicationsofabnormalsignalpatternsofbreakapartfishprobesusedinthediagnosisofboneandsofttissuetumours
AT christopherdavies implicationsofabnormalsignalpatternsofbreakapartfishprobesusedinthediagnosisofboneandsofttissuetumours
AT akankshafarswan implicationsofabnormalsignalpatternsofbreakapartfishprobesusedinthediagnosisofboneandsofttissuetumours
AT nischalanpillay implicationsofabnormalsignalpatternsofbreakapartfishprobesusedinthediagnosisofboneandsofttissuetumours
AT nischalanpillay implicationsofabnormalsignalpatternsofbreakapartfishprobesusedinthediagnosisofboneandsofttissuetumours