Dural Follicular Lymphoma: Case Report and Literature Review

Abstract

Follicular lymphoma (FL) usually has an indolent course and presents with painless, waxing and waning lymphadenopathy in the absence of systemic symptoms. It is uncommon for FL to present outside of lymph nodes, although it can develop in the gastrointestinal tract, skin, thyroid, and testes. Central nervous system (CNS) involvement in FL is rare. Most CNS lymphomas are diffuse large B-cell lymphoma, although Burkitt lymphoma, lymphoblastic lymphoma, and peripheral T-cell lymphoma are also observed. These tumors usually involve white matter but may also involve gray matter. Lymphomas of the dura are very uncommon and are usually mucosa-associated lymphoid tissue lymphomas. Here, we present a case of FL of the dura arising in a 62-year-old woman that was responsive to chemotherapy. According to a literature review, there have been 15 previously reported cases of FL of the dura. Dural FL has been most frequently treated with radiation and chemotherapy. Patients were still alive in all cases in which follow-up was reported. Although the sample size is small, these data suggest that dural FL, like other forms of FL, is an indolent disease that is associated with prolonged survival despite usually being incurable.

Keywords: central nervous system; dural follicular lymphoma; primary lymphoma.

Figure 1.

Coronal (left) and axial (right) magnetic resonance images demonstrating a 2.3 × 1.0 × 2.7 cm dural-based mass (yellow arrows) in the left frontoparietal region with associated thickening and enhancement of the adjacent dura. There is an extracranial component to the mass in the adjacent soft tissues without visible abnormalities of the bone. In addition, there are linear extension into the gyri of the adjacent brain parenchyma with an associated focal area of subcortical edema in the lateral aspect of the postcentral gyrus.

Figure 2.

(A) The dura demonstrates infiltration of fibrous tissue by a vaguely nodular lymphocytic infiltrate (hematoxylin and eosin, 40× magnification). (B) Closer inspection of 1 of the nodular areas reveals the infiltrate to consist of a mixture of small lymphocytes with cleaved nuclei (centrocytes) and large lymphocytes with multiple nucleoli (centroblasts) (hematoxylin and eosin, 400× magnification).

Figure 3.

(A) Lymphocytes express CD20, consistent with B cells (CD20 immunohistochemical stain, 200× magnification). (B) CD21 highlights retained follicular dendritic cell meshworks (CD21 immunohistochemical stain, 200× magnification). B cells show aberrant co-expression of (C) Bcl-2 and (D) Bcl-6 (Bcl-2 and Bcl-6 immunohistochemical stains, 200× magnification). The overall morphological and immunophenotypic findings support the diagnosis of follicular lymphoma.