The diagnostic use of cytogenetic and molecular genetic techniques in the assessment of small round cell tumours

Abstract

The term ‘small round cell tumour’ contains a wide variety of highly malignant tumours: Ewing family of tumours, olfactory neuroblastoma (esthesioneuroblastoma), rhabdomyosarcoma, neuroblastoma, lymphoma, desmoplastic small round cell tumour, small cell osteosarcoma, small cell carcinoma, cutaneous neuroendocrine carcinoma (Merkel-cell carcinoma), small cell melanoma, and mesenchymal chondrosarcoma. All tumour types within this class have their own treatment regimens and the prognosis is different for each tumour type. Thus, a correct diagnosis is essential to design treatment correctly and to assess the patient's prognosis. Before the breakthrough of modern cytogenetic and molecular genetic techniques, the differential diagnostics was a true challenge to the histopathologist. Today the use of modern techniques has made the diagnostic process easier and yields more specific histopathological diagnoses. This review covers the use of cytogenetic and molecular genetic techniques in the assessment of small round cell tumours.