Extracranial arteriovenous malformations: natural progression and recurrence after treatment

Arteriovenous malformation is a dynamic vascular anomaly; it expands with age and after treatment. This study analyzed the pattern of arteriovenous malformation progression and frequency of recurrence after therapy.

Patients with cutaneous and soft-tissue arteriovenous malformation were reviewed. Progression was defined as advancement to a higher Schobinger stage (I through IV) before treatment. Recurrence was defined as expansion following embolization or resection. The effect of sex, location, size, adolescence, pregnancy, and stage on progression or recurrence was analyzed.

The study included 272 patients. Children with stage I arteriovenous malformation had a 43.8 percent risk of progression before adolescence and an 82.6 percent risk before adulthood; the remaining children had progression in adulthood. Progression was more common during adolescence (56.0 percent; 95 percent confidence interval, 46.5 to 65.2) compared with childhood (38.8 percent; 95 percent confidence interval, 32.4 to 45.4) (p = 0.002). The average age at progression was 12.7 +/- 11.1 years. Diffuse arteriovenous malformations were more likely to progress compared with localized lesions (p < 0.001). Sex (p = 0.46), location (p = 0.36), and pregnancy (p = 0.20) did not influence expansion. Resection (with or without embolization) had a lower recurrence rate (81 percent) and longer time to recurrence (42.7 percent >1 year), compared with embolization alone (98 percent and 14.4 percent >1 year, respectively) (p < 0.001). Recurrence was less likely when lower staged lesions were treated (p < 0.001) and did not correlate with sex (p = 0.10), location (p = 0.60), size (p = 0.07), or age (p = 0.21).

Arteriovenous malformation is likely to progress before adulthood, particularly during adolescence, and usually reexpands following treatment. Resection (with or without embolization) for lower staged or localized arteriovenous malformation offers the best chance for long-term control.