The surgical management of metastatic spinal disease: prospective assessment and long-term follow-up.

The last decade has witnessed a resurgence of interest in the surgical treatment of metastatic spinal disease to compliment radiotherapy. A recent randomized controlled trial looking directly at this issue concluded strongly in favour of a combination of surgical decompression and radiotherapy, and there is now growing enthusiasm for surgery to play a role in the management of these patients. We present a prospective cohort study of 62 patients who presented with metastatic cord or cauda equina compression, and were treated with surgical decompression and fixation where necessary. Patients were treated by one surgeon working in a single unit. They were followed-up long term and were assessed objectively, by clinical assessment and prospective questionnaires that included SF36, visual analogue pain scores and Roland Morris back pain scores. Sixty-two patients with a median age of 62 (22-79 years, 27 male) were included in the study. The commonest primary tumours were breast (26%) and lymphoma (13%). The majority of patients had involvement of thoracic vertebrae (58%). 56% of patients were alive at 1 year and 28% at 3 years, with significant improvements observed in both walking and continence. Similarly, significant improvements were seen in SF36 quality of life scores as well as pain. With careful patient selection, long-term survival and good quality of life can be achieved. However, not every patient is suitable or appropriate for surgery, and the discussion focuses on where the surgical threshold should be set.

High-dose radiotherapy in the management of chordoma and chondrosarcoma of the skull base and cervical spine: Part 1--Clinical outcomes.

AIMS: Patients with chordoma and chondrosarcoma in the skull base present a complex multidisciplinary problem. These tumours are rare and occur in difficult anatomical regions. We reviewed the local control and survival of patients treated in our centre. MATERIALS AND METHODS: Between 1996 and 2005, 12 adult cases of chordoma (nine) and chondrosarcoma (three) in the skull base or cervical spine were treated in our centre. The median follow-up is currently 38 months. One patient was treated with palliative intent. In 10 cases the prescription dose was 65 Gy in 39 fractions. The target volumes were measured, and the target maximum and minimum doses and the equivalent uniform dose (EUD) for the phase I plans were recorded. RESULTS: Local control was achieved in 11 of 12 cases. One chordoma patient failed locally, and one other died of metastatic disease despite local control. The 3- and 5-year cause-specific survival for the series was 88 and 75%, respectively. The mean phase I planning target volume (PTV) was 120.4 cm(3). The median minimum dose in the phase I PTV was 81.0%. The median EUD (expressed as a percentage of the prescribed dose) for the phase I PTV, calculated using a value for the exponent a of -15, was 98.3%. The phase I EUD was below 80% in two of the 12 cases. CONCLUSIONS: Our results confirm a need for aggressive local surgery and high-dose radiotherapy, and endorse multidisciplinary working. Although charged particle therapy is accepted as providing optimal treatment plans, in eight of our patients travel abroad would not have been feasible. This series provides encouraging results for carefully planned photon conformal radiotherapy, carried out in close collaboration with a specialist surgical team.

Conformal rotation therapy with central axis beam block is a feasible alternative to intensity-modulated radiotherapy for chordomas of the cervical spine.

AIMS: Paraspinal tumours, such as chordoma, represent a treatment challenge for oncologists, requiring high dose to the target volume without exceeding the tolerance dose of the spinal cord. Intensity-modulated radiotherapy (IMRT) is helpful in achieving sharp dose gradients and conformation of dose to the target volume. We present a simpler technique--conformal rotation therapy with a central axis beam block (CRT + BB), which can provide similar dose distributions. MATERIALS AND METHODS: A patient with a cervical chordoma developed postoperative recurrence and was treated with high-dose palliative radiotherapy. Treatment was delivered using CRT + BB, with three fixed beams and three coplanar arcs. A dose of 62 Gy in 31 fractions was delivered to the 100% isodose, giving a maximum spinal cord dose of 49.6 Gy. The patient relapsed 2 years later, and was re-treated using the same technique to a dose of 57 Gy in 30 fractions. Estimates of spinal cord repair rates in primates were used to determine the tolerance dose of the spinal cord for re-treatment. The patient remained well for a further 25 months before developing local recurrence, which was treated with palliative chemotherapy. RESULTS: Re-treatment plans using CRT + BB and IMRT were compared. Dose-volume histograms show equivalence of dose to the spinal cord, although the IMRT plan delivered a slightly higher dose to tumour and lower dose to surrounding soft tissues. CONCLUSION: Treatment using CRT + BB requires careful planning and discussion with neurosurgeons before surgery. The normal curvature of the cervical spine must be eliminated if possible, and the patient must be immobilised with the neck horizontal. If these geometric constraints can be satisfied, then CRT + BB can be used as a safe and effective alternative treatment to IMRT for tumours at this site.

Assessment of fusion after anterior cervical discectomy.

There is no established method to assess fusion in patients following anterior cervical discectomy. In this study we have made a series of measurements to detect movement between vertebrae adjacent to an operated space. The absence of movement implies structural union between adjacent vertebrae. Measurements have been made in two distinct surgical groups. Group A patients had anterior cervical discectomy with insertion of a BOP graft into the disc space. Group B patients underwent simple anterior cervical discectomy with no spacer or graft material inserted, the disc space being left empty. Details of the measurements and interpretation of results are described. In the absence of a 'gold standard' to assess bony union we propose that these measurement methods provide an objective and scientific method to assess fusion at the operated level after anterior cervical discectomy. Objective measurement of fusion will allow comparison between different surgical techniques that claim fusion as an end point. It will also become possible to study the influence of fusion on clinical outcome in different surgical populations.