Multiple spinal cavernous malformations with atypical phenotype after prior irradiation: case report.

Objective And Importance: This is the first reported case of histologically proven multiple spinal cavernous malformations (CMs) associated with previous irradiation. There are only two cases reported in the literature of solitary spinal CM after irradiation. In addition, the lesions in our patient had an atypical magnetic resonance imaging appearance mimicking intraspinal drop metastasis.

Clinical Presentation: A 33-year-old man had an incidental finding of multiple enhancing intraspinal lesions as revealed by magnetic resonance imaging during staging tests for hepatocellular carcinoma. He had a history of Wilms' tumor at a young age with irradiation to the abdomen and pelvis. His family history included a paternal cousin with multiple cerebral CMs. The diagnosis of spinal drop metastasis was made, and further intervention was undertaken for confirmation.

Intervention: The patient underwent a lumbar laminectomy with durotomy and excision of two of the lesions. Macroscopic analysis revealed mulberry-like appearance with nerve root involvement, and pathological analysis confirmed the diagnosis of CM. Genetic testing of the patient and his affected cousin was negative for the CCM1 gene.

Conclusion: The occurrence of multiple spinal lesions in the context of known neoplasia indicates a diagnosis of metastasis. Spinal CMs were not suspected preoperatively because of the atypical appearance revealed by magnetic resonance imaging scans, with uniform contrast enhancement and absence of hemosiderin rim. This case report is discussed relative to previous literature regarding radiation-induced CMs and other known causes of the disease.