Primary CNS Extranodal Marginal Zone B-Cell Lymphoma: A Case Series of 2 Patients Treated with External Beam Radiation Therapy

Abstract

Primary CNS extranodal marginal zone B-cell lymphoma (MZBL) is a rare low-grade non-Hodgkin lymphoma characterized predominantly by small B cells, plasma cells, monocytoid cells, and scattered large immunoblasts. As a slow-growing tumor that remains localized, primary CNS MZBL carries an excellent clinical prognosis. Here, we report two cases of primary CNS MZBL successfully treated using external beam radiation therapy along with a literature review.

Keywords: B cell; Central nervous system lymphoma; Extranodal marginal zone lymphoma; Marginal zone B-cell lymphomas; Radiation therapy.

Fig. 1

Initial head MRI showing the enhancing extra-axial mass along the right tentorium in sagittal (a) and axial (b) planes.

Fig. 2

MRI of the head 1 month following completion of RT showing decreased size of the extra-axial mass on the right with no new areas of enhancement in axial (a), sagittal (b), and coronal (c) planes. RT, radiation therapy.

Fig. 3

MRI of the head 5 months following completion of RT showing further decrease in size of the extramass on the right, extending along the right tentorial leaflet with decreased leptomeningeal enhancement. No new areas of enhancement were detected in axial (a), sagittal (b), and coronal (c) planes. RT, radiation therapy.

Fig. 4

Initial head MRI showing the multifocal peripherally enhancing lesions involving the splenium and posterior body of the corpus callosum, bilateral basal ganglia, and left corona radiata in axial (a, b), sagittal (c), and coronal (d) planes.

Fig. 5

MRI of the head 4 months following completion of CT showing decreased hyperintensity of the lesions involving the splenium and posterior body of the corpus callosum, bilateral basal ganglia, and left corona radiata in axial (a, b), sagittal (c), and coronal (d) planes.