Soft tissue tumours are a heterogeneous group of neoplastic lesions that arise from mesenchymal cells. Classifi cation of these tumours has historically been based on morphology with ancillary histochemical and immunohistochemical techniques. Improved cytogenetic studies and advances in molecular genetics have led to increased understanding of the pathology and classifi cation of these tumours. Genetically, soft tissue tumours can be divided into four categories. These include tumours with reciprocal translocations and otherwise simple karyotypes, tumours with characteristic amplifi cations, tumours with specifi c driver mutations, and those with complex karyotypes associated with chromosomal instability.
Knowledge of these genetic abnormalities and application of molecular diagnostic techniques such fl uorescence in situ hybridisation and mutation screening in histopathological practice is currently driving a revolution in how these tumours are diagnosed and managed.