title: Postradiation lumbosacral radiculopathy with spinal root cavernomas mimicking carcinomatous meningitis.
abstract: Lumbosacral radiculopathy is a rare complication of radiotherapy and may be challenging to differentiate from diagnosis of a tumor recurrence. We reviewed the records of three patients with a past history of cancer and radiotherapy who were referred for suspicion of carcinomatous meningitis on lumbar MRI, but whose final diagnosis was radiation-induced lumbosacral radiculopathy. The three patients developed a progressive lumbosacral radiculopathy at 20, 13, and 47 years after lumbar radiotherapy delivered for renal cancer, Hodgkin's disease, and a seminoma, respectively. MRI showed a diffuse, nodular enhancement of the cauda equina nerve roots on T1 sequences, suggestive of leptomeningeal metastasis. A slowly progressive clinical course over several years and negative cerebrospinal fluid cytologic analysis ruled out the diagnosis of carcinomatous meningitis. Because of the radiologic findings, a biopsy was performed in two patients. In the first, a biopsy limited to the arachnoid excluded a malignant infiltration. In the second, a biopsy of the enhancing lesions demonstrated spinal root cavernomas. These observations, together with three recent case reports in the literature, delineate a syndrome of "radiationinduced lumbosacral radiculopathy with multiple spinal root cavernomas" that mimics carcinomatous meningitis on MRI. Its diagnosis is important in order to avoid inappropriate treatment and useless or dangerous spinal root biopsies.
authors.affiliation: Service de Neurologie Mazarin, APHP, Groupe hospitalier Pitié-Salpêtrière, Paris, France.
authors.forename: François
authors.initials: F
authors.lastname: Ducray
authors.forename: Rémy
authors.initials: R
authors.lastname: Guillevin
authors.forename: Dimitri
authors.initials: D
authors.lastname: Psimaras
authors.forename: Marc
authors.initials: M
authors.lastname: Sanson
authors.forename: Karima
authors.initials: K
authors.lastname: Mokhtari
authors.forename: Sylvie
authors.initials: S
authors.lastname: Delanian
authors.forename: Soledad
authors.initials: S
authors.lastname: Navarro
authors.forename: Thierry
authors.initials: T
authors.lastname: Maisonobe
authors.forename: Philippe
authors.initials: P
authors.lastname: Cornu
authors.forename: Khê
authors.initials: K
authors.lastname: Hoang-Xuan
authors.forename: Jean-Yves
authors.initials: JY
authors.lastname: Delattre
authors.forename: Pierre-François
authors.initials: PF
authors.lastname: Pradat