The molecular characterisation of unusual subcutaneous spindle cell lesion of breast
- Elena A Takano1,
- Toni-Maree Rogers1,
- Richard J Young2,
- Mukta Rayoo1,
- Phillip Kostos3,
- Ross Ferguson3,
- Ian G Campbell4,
- Maria Debiec-Rychter5,
- Stephen B Fox1,6
- 1Department of Pathology, Peter MacCallum Cancer Centre, East Melbourne, Victoria, Australia
- 2Research Division, Peter MacCallum Cancer Centre, East Melbourne, Victoria, Australia
- 3Frankston Hospital, Frankston, Victoria, Australia
- 4VBCRC Cancer Genetics Laboratory, Peter MacCallum Cancer Centre, East Melbourne, Victoria, Australia
- 5Department of Human Genetics, Catholic University of Leuven, Leuven, Belgium
- 6Department of Pathology, The University of Melbourne, Parkville, Victoria 3010, Australia
- Correspondence to Elena A Takano, Peter MacCallum Cancer Centre, Pathology, Molecular Pathology Research and Development, St. Andrews Place, East Melbourne 3002, Australia;
Contributors EAT contributed in manuscript preparation and data analysis. TR and RJY contributed in EGFR FISH. MR collated sample material and contributed in manuscript preparation. PK contributed in pathology and manuscript approval. RF contributed in surgery and manuscript approval. IGC contributed in SNP data analysis and manuscript approval. MDR contributed in FISH and manuscript approval. SBF conceptualised the study and contributed in data analysis and manuscript preparation.
- Accepted 20 March 2012
- Published Online First 20 April 2012
Background Spindle cell lesions of the breast represent an interesting diagnostic challenge as they comprise a wide range of tumours that are rare. Differentiating dermatofibrosarcoma protuberans (DFSP) from other dermatofibromas using CD34 immunohistochemistry alone is difficult; therefore, fluorescence in situ hybridisation (FISH) analysis is often employed to identify typical COL1A1–PDGFB fusion or gene rearrangement. Although molecular confirmation of diagnosis is unnecessary in the majority of DFSP cases, the detection of chromosomal rearrangement is valuable in tumours that show unusual clinicopathological features as in this study the authors report a case of DFSP of breast that did not show any typical known molecular features.
Methods and results Morphological and immunohistochemical study was highly suggestive of the diagnosis of DFSP. To further investigate this case, DNA copy number alterations were investigated by the 250 K Affymetrix SNP Mapping array. DNA analysis did not show any of the known translocations reported in DFSP or any known solid tumour category. However, in addition to copy number changes on chromosome 1, amplification of chromosome 7p which contains the epidermal growth factor receptor (EGFR) gene was observed. Results from EGFR FISH showed an increase in EGFR gene to chromosome 7 ratio (3:1) suggesting amplification of the EGFR gene.
Conclusion This case of an unusual DFSP demonstrates that genomic interrogation provides additional potential targets such as a therapeutic avenue with anti-EGFR therapies and shows the power of molecular characterisation of unusual tumours for a personalised medicine approach.
- Dermatofibrosarcoma protuberans
- spindle cell
- breast cancer
- cancer research
- liver cancer
- breast pathology
- blood vessels
Funding This study was funded by a grant from the Victorian Breast Cancer Research Consortium, Australia.
Competing interests None.
Ethics approval Ethics approval was obtained from the Peter MacCallum Cancer Centre Ethics Committee.
Provenance and peer review Not commissioned; externally peer reviewed.