Giant cell tumour of the sacrum: a suggested algorithm for treatment.

To investigate the outcome of our management of patients with giant cell tumour of the sacrum and draw lessons from this. A retrospective review of medical records and scans for all patients treated at our unit over the past 20 years with a giant cell tumour of the sacrum. Of the 517 patients treated at our unit for giant cell tumour over the past 20 years, only 9 (1.7%) had a giant cell tumour in the sacrum. Six were female, three male with a mean age of 34 (range 15-52). All, but two tumours involved the entire sacrum and there was only one purely distal to S3. The mean size was 10 cm and the most common symptom was back or buttock pain. Five had abnormal neurology at diagnosis, but only one presented with cauda equina syndrome. The first four patients were treated by curettage alone, but two patients had intraoperative cardiac arrests and although both survived all subsequent curettages were preceded by embolisation of the feeding vessels. Of the seven patients who had curettage, three developed local recurrence, but all were controlled with a combination of further embolisation, surgery or radiotherapy. One patient elected for treatment with radiotherapy and another had excision of the tumour distal to S3. All the patients are alive and only two patients have worse neurology than at presentation, one being impotent and one with stress incontinence. Three patients required spinopelvic fusion for sacral collapse. All patients are mobile and active at a follow-up between 2 and 21 years. Giant cell tumour of the sacrum can be controlled with conservative surgery rather than subtotal sacrectomy. The excision of small distal tumours is the preferred option, but for larger and more extensive tumours conservative management may well avoid morbidity whilst still controlling the tumour. Embolisation and curettage are the preferred first option with radiotherapy as a possible adjunct. Spinopelvic fusion may be needed when the sacrum collapses.