The association of endometrioid carcinoma of the ovary and primary carcinoma of the endometrium is well recognised. These tumours are often synchronous in occurrence. Oestrogen stimulation is often postulated as a significant factor in the development of the endometrial carcinoma in such cases. We describe the case of a patient who developed a mucinous endometrial carcinoma 18 years after initial bilateral ovariectomy. The aetiology and pathogenesis of the uterine tumour is discussed.