Intravascular lymphoma or intravascular lymphomatosis (IVL) is an uncommon extranodal lymphoma, which gives rise to exclusively intravascular tumor growth. In 1/3 of the reported cases the disease debuts with involvement of the nervous system, which is particularly susceptible. Over the clinical course of the disease, 2/3 of the patients will present neurological symptoms. Owing to its characteristic growth pattern, IVL can give rise to very different central or peripheral nervous system neurological syndromes. Not infrequently a single patient will present more than one neurological syndrome. Moreover, the specificity of the neurological tests is low. All these factors explain the difficulties involved in diagnosing this entity and the fact that in most cases the diagnosis is established on autopsy study. This article presents the clinical, biological, radiological and post-mortem neuropathological findings in an immunocompetent patient with IVL. The onset was a cauda equina syndrome and showed multiple and varied neurological manifestations during the course of the disease, which progressed in the months before death. Spinal cord biopsy performed in life did not provide diagnostic findings because the vessels showed no neoplastic involvement. Immunohistochemical findings demonstrated large B-cell lymphoma. A review of the neurological features described in previously published cases of IVL is provided.