De Novo Cavernoma Formation in a Patient With Cowden Syndrome and Lhermitte-Duclos Disease

Cowden syndrome (CS) is an autosomal dominant genodermatosis with a predisposition for the development of multiple cancers, benign hamartomas, and extracranial vascular malformations. Rarely, intracranial lesions like meningiomas and vascular malformations can also be present with CS. These vascular malformations include developmental venous anomalies, arteriovenous fistulae and cavernomas. Most cases of cavernomas are thought to be congenital, although in recent literature they have been shown to occur de novo with other conditions (e.g., other vascular malformations, trauma, postcranial surgery, viral infection, and genetic disorders).

We present a 29-year-old woman who was diagnosed with Lhermitte-Duclos disease after episodes of persistent generalized headaches. She underwent a foramen magnum decompression and was subsequently diagnosed with CS. Ten years, later she was also diagnosed with 2 cerebral cavernomas that were not present on her prior monitoring scans.

We present a case of a patient with CS and LDD who had de novo cavernoma development several years after the initial diagnosis, as well as a review of the literature. We highlight the need of surveillance neuroimaging for patients with CS, as there is the risk of new development of vascular abnormalities (particularly cavernomas).