The most common malignant tumour of the uterus is endometrioid endometrial cancer. However, many less common malignant diseases also develop in the uterus, including both carcinomas and sarcomas. Most notable of these tumours are papillary serous carcinomas, clear-cell carcinomas, carcinosarcomas, stromal sarcomas, and leiomyosarcomas. These less common cancers can be aggressive, and account for a greatly disproportionate amount of deaths from uterine cancers. Because they are uncommon, physicians will usually have seen only a few cases, and randomised data to guide treatment often do not exist. This review summarises the epidemiology, clinical characteristics, and prognoses of the less common malignant diseases of the uterus, and presents the information available to guide the clinician about treatment options.