Clinical course of patients with conservatively managed cerebral cavernous malformations

Introduction: There is uncertainty whether patients with a cerebral cavernous malformation (CCM) should undergo conservative or surgical treatment, resulting in practice variation among hospitals. Our objective was to report clinical outcomes of patients with primarily conservatively managed CCMs. Patients and methods: This single-center cohort study included consecutive adult CCM patients, diagnosed in 2000–2023, who underwent conservative management as primary treatment strategy. Data were extracted from medical records, and we systematically conducted telephone and questionnaire follow-up. Functional status was assessed on the modified Rankin Scale (mRS). Results: Of 345 patients, we included 265 patients with a CCM (median age 46 years; 45% male). At baseline, 131 (49%) patients presented with symptomatic hemorrhage (SH), and 134 (51%) with other symptoms or asymptomatically. During 58 months (IQR 35–94) median follow-up, 51 (19%) patients experienced a SH, 33 (12%) a seizure, and 13 (5%) focal neurological deficits. Fourteen (5%) patients underwent intervention (surgery n = 11, radiosurgery n = 4). Presentation with SH was associated with higher annual bleeding rates (6.0% vs 1.5%, p < 0.001), and higher cumulative 5-/10-year bleeding risks (31%/41% vs 7%, p < 0.001). Brainstem CCM was associated with higher cumulative 5-/10-year bleeding risks (27%/38% vs 17%/21%, p = 0.038). Nineteen (7%) patients died; two (0.8%) directly attributable to CCM. Of 246 surviving patients, 205 (83%) completed the questionnaire. At follow-up, 172/224 (77%) patients were functionally independent (mRS score ⩽2). Discussion and conclusion: The majority of conservatively managed CCM patients remained free of a SH during follow-up. Few patients required intervention, and death attributable to the CCM was rare. These data may help patient counseling and treatment decisions.