An 89 year old woman had a two-month history of vaginal bleeding. Vaginal ultrasound examination showed an expanded endometrium. An outpatient endometrial biopsy was performed, which showed a moderately differentiated grade 2 endometrioid endometrial adenocarcinoma. Magnetic resonance imaging suggested that the tumour was minimally invasive and confined to the uterus (Fig. 1). The woman had limited exercise tolerance due to long-standing heart disease. Echocardiology confirmed moderate aortic stenosis. A cardiologist estimated that the chances of her surviving a general anaesthetic would be slightly greater than 50%. Several treatment options were discussed with the woman and her family. No treatment was rejected because the vaginal bleeding was increasing and was distressing for the woman and her family. Palliative treatment with radiotherapy and progesterone were also considered but rejected by the woman and her family. Therapeutic microwave ablation of the tumour was proposed.
The Royal United Hospital Research Ethics Committee considered an emergency proposal to treat the woman's minimally invasive endometrial carcinoma with microwave endometrial ablation. The Committee was satisfied that the woman and her family understood that this technique was entirely experimental in the current context and that other treatment options had been considered but rejected. Approval was granted. Microwave ablation of the endometrium was performed using a local anaesthetic block to the cervix. The cervix was easily dilated and as much tumour as possible was aspirated with a 7-mm diameter suction curette from the uterine cavity, which measured 11 cm in length. Uneventful microwave endometrial ablation was then performed. The treatment lasted for 6½ minutes and the entire cavity lining was ablated under transabdominal ultrasound surveillance. The woman did not experience any discomfort, significant bleeding or untoward side effects and was discharged from hospital on the following day.
She was seen three months later and remained well without any symptoms. An ultrasound examination showed the typical post-ablation echogenicity. The ablated zone around the cavity measured 12 mm anteroposteriorly. There was no loculation to suggest haematometra. However, a scan five weeks later suggested that the area of necrosis and scarring was not resolving. It measured 12 × 30 mm in the sagittal plane and the risk of residual disease was considered to be high. As significant uterine prolapse had been observed at the time of microwave ablation of the endometrium, a vaginal hysterectomy was performed under spinal anaesthesia. Although the procedure was technically straightforward the woman had a protracted recovery with episodes of cardiac failure, confusion as a result of cerebral hypoxia and vault sepsis, but eventually made a full recovery.
Macroscopic examination of the resected uterus revealed a sharply demarcated zone of yellowish brown necrotic tissue occupying the innermost 5–7 mm of the uterine wall (Fig. 2). Histological examination showed the endometrium to be completely necrotic (Fig. 3). A narrow zone of fibrous tissue separated the necrotic tissue from the underlying myometrium. Despite examination of sections from multiple blocks, no residual endometrial adenocarcinoma was identified, indicating that microwave ablation of the endometrium had successfully ablated the entire endometrial tumour. No lymphovascular invasion was identified and the endocervix and parametrial shavings were free of tumour. The woman remains free of disease 36 months later.