MRI of CNS lymphoma with choroid plexus involvement in five dogs and one cat

Abstract

Objectives To describe the clinical features, magnetic resonance imaging (MRI) findings, and outcome of dogs and cats with central nervous system (CNS) lymphoma that involved the choroid plexus. Materials and Methods A bi‐institutional retrospective study of MRI of dogs and cats with CNS lymphoma, in which the choroid plexus was affected on MRI. Signalment, clinical, MRI, clinicopathologic and histopathologic findings were recorded and evaluated. Results CNS lymphoma with choroid plexus involvement on the MRI was identified in five dogs and one cat. MRI revealed diffuse enlargement and multifocal nodularity in the choroid plexus in most cases, with the fourth ventricle the most common site affected. Five of the cases had signs of extraneural involvement (including the cat), while the sixth case was not staged. Four of five CSF samples analysed provided a diagnosis of lymphoma. Clinical Significance We report MRI findings of CNS lymphoma involving the choroid plexus. These results show the importance of recognising novel imaging patterns and the potential utility of CSF collection in diagnosing CNS lymphoma involving the choroid plexus ante mortem.

Neurolymphomatosis in a cat with diffuse neuromuscular signs including cranial nerve involvement

“…12,23 A few canine and feline cases of NL have been reported with histopathologically confirmed involvement of the meninges and choroid plexi that also did not show abnormalities on MRI. 24 Therefore, as in our case, MRI is not 100% sensitive for involvement of these structures in cases of NL. The MRI did show the bulla tympanica both being filled with fluid, which was confirmed to be purulent fluid on histopathology.…”

“…It is less common in cats, where in a publication, only two out of 23 cats (8%) having CNS lymphoma had choroid plexus infiltration 12,23 . A few canine and feline cases of NL have been reported with histopathologically confirmed involvement of the meninges and choroid plexi that also did not show abnormalities on MRI 24 . Therefore, as in our case, MRI is not 100% sensitive for involvement of these structures in cases of NL.…”

Primary central nervous system diffuse large B-cell lymphoma in fourth ventricle: Case report and literature review

“…Intraventricular lymphoma is rare, its MRI enhancement images often showing T1 showed equal or slightly lower signal, T2 showed equal or slightly higher signal (similar to gray matter) with cotton-like or nodular shape. [ 8 ] It is usually iso-intensity on MRI plain scan with uniform signal. And it often goes along with strong peritumoral edema with uniform enhancement which presents bull eye sign.…”

Feline lymphoma of the nervous system. Immunophenotype and anatomical patterns in 24 cases

“…The CD44 is an extensively expressed cell surface glycoprotein of 80–200 kDa involved in cell–cell adhesion ( 22 ) and cell-extracellular matrix (ECM) interaction ( 22 ) besides lymphocyte activation ( 16 ). Many CD44 isoforms have been detected supporting that the effects of its expression in tumors can be produced by several mechanisms ( 22 ).…”

“…In about 50% of cases, the intra-axial brain lymphoma grows as a lymphomatosis cerebri consisting of a diffuse parenchymal infiltration ( 8 ). Although less common, additional anatomical patterns of the feline nervous system lymphoma consist of leptomeningeal lymphomatosis, also known as “lymphomatous meningitis” ( 11 , 12 ), angiotropic lymphoma ( 13 , 14 ), and lymphomatous choroiditis ( 5 , 6 , 15 , 16 ). If leptomeningeal lymphomatosis and lymphomatous choroiditis represent infiltrative patterns of neoplastic lymphocytes occurring in the leptomeninges or choroid plexuses, respectively ( 5 ), the angiotropic lymphoma is characterized by the proliferation of neoplastic lymphocytes within the lumen of small blood vessels ( 5 ).…”