Recent advances in the histopathology of stromal tumours of the endometrium

Stromal tumours of the endometrium can be difficult to distinguish from smooth muscle tumours of the uterus when evaluating conventional morphology alone. This review focuses on the value of immunohistochemical markers for diagnosing endometrial stromal tumours with emphasis on the recent literature. Low-grade endometrial stromal sarcomas show consistent expression of CD10 but the specificity of staining is low, since approximately 50% of highly cellular leiomyomas and almost all leiomyosarcomas are also positive for CD10. Therefore, a panel of markers must be used for distinguishing an endometrial stromal tumour from a uterine smooth muscle tumour, including antibodies against CD10, desmin, h-caldesmon and oxytocin receptors. On rare occasions, additional markers such as inhibin, CD117 and HMB-45 may be of help in the differential diagnosis.