Spinal cord lesions caused by arteriovenous malformation: clinical course and risk of cancer.

ABSTRACT

PURPOSE: Patients with nontraumatic myelopathy caused by arteriovenous malformation (AVM) are encountered in cohorts of traumatic myelopathy (SCI) patients. The study describes the clinical course of SCI secondary to AVM and compares the incidence of cancer with that in SCI patients. PARTICIPANTS: Twenty-three patients with AVM and 219 patients with SCI patients aged 50 years and older. METHODS: The 2 groups were described by the character of paralysis and compared for the incidence of cancer in a retrospective review of records from the index year 1989. RESULTS: Twenty-three patients with AVM became paralyzed, with onset from age 22 years to 85 years (mean, 53 years). The presenting symptoms were pain (usually back pain), paresthesias, and weakness. The clinical picture varied, with evolution of symptoms reported over a wide period ranging from minutes to 27 years (median, 6 months). Levels of the spinal cord damage were thoracic in 74% of the AVM group vs 40% for the SCI group, P = .004. For patients with AVM, grade of paralysis was American Spinal Injury Association D (some significant use of the legs) in 26% vs 16% for patients with SCI, P = .38. Nine patients with AVM (39%) developed cancer (skin, brain, blood, thyroid, liver, bladder, and prostate at age 66 +/- 7 years) with an incidence of 5.92 cancers/100 patient years. Thirty-five patients with SCI (9%) had cancer (skin, blood, lung, bowel, bladder, and prostate, age 67 +/- 5 years) develop at a rate of 1.70 cancers/100 patient years, 95% confidence interval = 1.89-6.51 for the difference, P = .001. CONCLUSION: Patients with nontraumatic spinal cord lesions caused by AVM often present with pain, may have a protracted clinical course, and have cancer develop more often than do those with traumatic SCI.