Late Cerebrovascular Complications After Radiotherapy for Childhood Primary Central Nervous System Tumors

Abstract

Background: Brain radiotherapy plays a central role in the treatment of certain types of childhood primary central nervous system tumors. However, damage to surrounding normal brain tissue causes different acute and chronic medical and neurological complications. Despite the expected increase in number of childhood primary central nervous system tumor survivors, studies assessing the occurrence of late cerebrovascular complications, such as cavernoma, moyamoya, microbleeds, superficial siderosis, and stroke are sparse.

Methods: We undertook a retrospective consecutive case series review describing the occurrence and characteristics of late cerebrovascular complications in 100 survivors of childhood primary central nervous system tumors treated with radiotherapy. Demographic, clinical, and radiological findings including gradient echo brain magnetic resonance data were retrieved.

Results: Late cerebrovascular complications were found in 36 (36%) of the patients included in the study. Mean age at radiotherapy was 8.6 years (3-17) and at diagnosis was 23.9 years (3-38). The majority were males (21; 58%). The most common complications were microbleeds (29/36; 80.6%) and cavernomas 19 (52.8%). In seven (19.4%), late cerebrovascular complications were symptomatic: epilepsy (two), motor and language deficit (two), and sensorineural hearing loss and progressive ataxia (three) associated with cavernomas, stroke, and superficial siderosis, respectively. Follow-up length was associated with an increased diagnosis of late cerebrovascular complications (P < 0.0001). Late cerebrovascular complications occurred more commonly in children treated with whole-brain radiation therapy (P = 0.046). Factors such as sex, chemotherapy, and histological type of tumor were not correlated with the occurrence of late cerebrovascular complications.

Conclusion: Although not usually symptomatic, late cerebrovascular complications occur frequently in survivors of childhood primary central nervous system tumors treated with radiotherapy. Prolonged follow-up increases the probability of diagnosis. The impact and prognostic value of these late cerebrovascular complications is yet to be clarified.

Keywords: cavernoma; late complications; microbleeds; radiotherapy; stroke; superficial siderosis.