Clinical investigation
Efficacy and morbidity of arc-therapy radiosurgery for cerebral arteriovenous malformations: a comparison with the natural history

Presented at the 12th Meeting of the European Cancer Conference (ECCO 12), Copenhagen, September 21–25, 2003.
https://doi.org/10.1016/j.ijrobp.2003.09.005Get rights and content

Abstract

Purpose

To report the results of arc-therapy radiosurgery for cerebral arteriovenous malformation (AVM) and to compare the adverse event rate with the rate expected from the natural history.

Methods and materials

We performed a retrospective study of our 118 first patients with a mean follow-up of 46 months (range, 5–105 months). The AVMs had features indicating a poor prognosis at initial presentation and had already been treated by previous embolizations in 88% of patients. The mean volume of the targets was 7.4 cm3 (range, 0.3–28.3 cm3). The mean minimal and maximal dose was 17.7 Gy (range, 10–25 Gy) and 24.5 Gy (range, 17–36 Gy), respectively.

Results

The crude and 5-year actuarial rate of cure (total obstruction of the AVM shunt at angiography) was 54% (60 of 112) and 77%, respectively. The only independent prognostic factor of cure was the AVM volume (crude cure rate 67% for <7 cm3 vs. 35% for ≥7 cm3; p = 0.001). No patient died. Transient and permanent complications and hemorrhage occurred in 5%, 1.7%, and 6% of patients, respectively. The annual risk of an adverse event (hemorrhage or complication) was 3.9%.

Conclusion

The results of our series showed that radiosurgery, performed alone or after prior shrinkage of the AVM by embolization, is both effective and well tolerated, with a rate of adverse events comparable to that expected from the natural history.

Introduction

The choice of therapeutic modality to treat cerebral arteriovenous malformations (AVMs) is highly controversial. These lesions, when untreated, represent a consequential threat to patients, with an annual rate of major hemorrhage of 2–17% 1, 2, 3, 4. Intracerebral hemorrhages have been reported as lethal in up to 29% of cases (2). During the past decades, surgery has been considered the standard treatment by many authors (5). The treatment of AVM by radiosurgery still raises controversy. Some have supported the option of observation for inoperable AVMs rather than nonsurgical treatment, because only scant evidence is available regarding the value of nonsurgical treatment in terms of survival, quality of life, and neurologic progression-free survival (6). We therefore compared the actuarial rates of hemorrhage and severe complication-free survival of our series of patients with that observed in the natural history of untreated AVMs.

Section snippets

Patients

At the University Hospital of Nancy, 217 patients have been treated by linear accelerator radiosurgery since 1992. We report the results of a retrospective study of the 118 first patients (55 men and 63 women) treated between July 1, 1992 and June 30, 1998 (Table 1, Table 2). The closing date of the study was December 31, 2001. The mean follow-up was 46 months (range, 5–105 months; median, 44 months). Of the 118 patients, 2 (2%) were lost to follow-up. The mean age was 35 years (range, 13–65

Efficacy

The cure rate was 54% (60 of 112) among patients evaluated by either angiography or MRI. All cures were confirmed by angiography. When only considering evaluations performed at least 18 months after radiosurgery, the cure rate was 57% (60 of 106). The actuarial cure rate was 77% (range, 76.9–77.1%) at 5 years (Fig. 1). One patient developed a new contralateral AVM. Of 112 patients, 83 (74%) reached cure or a reduction of >95% of their initial volume.

Prognostic factors of cure

No statistically significant differences

Discussion

Therapeutic decision-making for cerebral AVMs is particularly difficult. AVMs present a statistical risk of intracerebral hemorrhage with resulting functional and even vital complications at stake. Physicians who are confronted with this issue are either determined to treat or extremely reluctant. For this reason, randomized studies have proved very difficult. All effort must therefore be made to appreciate, with the highest precision, the statistical gain achieved by treatment as opposed to no

Conclusion

The results of our series show that our treatment strategy, with radiosurgery performed alone or after prior shrinkage of the AVM volume by embolization, is both effective (5-year actuarial cure rate 77%) and well tolerated, with a rate of adverse effects (complications and/or hemorrhage) comparable to that of untreated patients and with no mortality. Our results also confirmed the importance of size (±7 cm3) as a curative prognostic factor. No hemorrhage occurred in patients after either total

Acknowledgements

The authors thank M. Maire for her helpful collaboration in the preparation of this manuscript.

References (39)

  • R.D Brown et al.

    The natural history of unruptured intracranial arteriovenous malformations

    J Neurosurg

    (1988)
  • C.J Graf et al.

    Bleeding from cerebral arteriovenous malformations as part of their natural history

    J Neurosurg

    (1983)
  • The Arteriovenous Malformation Study Group. Arteriovenous malformations of the brain in adults. N Engl J Med...
  • M Brada et al.

    How effective is radiosurgery for arteriovenous malformations?

    J Neurol Neurosurg Psychiatry

    (2000)
  • R.F Spetzler et al.

    A proposed grading system for arteriovenous malformations

    J Neurosurg

    (1986)
  • O.O Betti et al.

    Stereotactic radiosurgery with the linear acceleratorTreatment of arteriovenous malformations

    Neurosurgery

    (1989)
  • E.L Kaplan et al.

    Nonparametric estimation from incomplete observations

    J Am Stat Assoc

    (1958)
  • N Mantel et al.

    Chi-square with one degree of freedomExtension of the Mantel-Haenszel procedure

    J Am Stat Assoc

    (1963)
  • D.R Cox

    Regression models and life table

    J R Stat Soc

    (1972)
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