Bilateral ocular panadnexal mass as initial presentation of systemic blastoid variant of mantle-cell lymphoma

A rare case of orbital mantle cell lymphoma presenting as a well-demarcated mass on magnetic resonance imaging

A 71-year-old male presented with painless and slowly progressive proptosis of the right eye. The patient had no history of cancer and was in good health. Orbital magnetic resonance imaging showed a well-demarcated, slightly lobulated intraconal orbital mass hypo-isointense on T1- weighted and isointense on T2-weighted images, demonstrating contrast enhancement in the right orbit. The lesion had a central cavitary region. An anterior orbitotomy with lower lid crease incision was performed and the lesion was excised in toto. Histopathologic examination revealed diffuse infiltration of monomorphic population of small lymphoid cells. Immunohistochemical staining demonstrated diffuse and strong positivity for CD20, CD5, and cyclin D1. Histopathological and immunohistochemical findings were consistent with mantle cell lymphoma. Positron emission tomography-computed tomography did not show systemic involvement. The patient underwent orbital external beam radiotherapy (36 Gy). There was no recurrence and/or systemic involvement at 2.5 years follow-up.

CD5-Negative Primary Mantle Cell Lymphoma Presenting with a Bilateral Conjunctival Mass: A Potential Diagnostic Pitfall

Mantle cell lymphoma is a B-cell malignancy, which, in its classic form, usually involves lymph nodes and extranodal sites, and, among the extranodal sites, the gastrointestinal tract and the Waldeyer's ring are most prevalent. MCL is rarely reported in the ocular adnexa, a site more frequently affected by extranodal marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue, which is a form of low-grade malignancy. The diagnosis of MCL presenting in the ocular adnexa requires special attention as its rarity in this location combined with the not uncommon CD5 negativity of the disease when occurring in the ocular adnexa, may lead the pathologist to overlook the diagnosis and misinterpret MCL as marginal zone B cell lymphoma, which has a totally different behavior. Herein, we present a case of primary bilateral conjunctival CD5-negative MCL in a patient having no other sites affected by lymphoma and we discuss possible diagnostic pitfalls.

Orbital lymphoma

Orbital lymphomas constitute 50-60% of ocular adnexal lymphomas. A total of 2211 cases of orbital lymphoma with a known subtype have been reported in the last 24 years (1994-2017). The vast majority of orbital lymphomas are of B-cell origin (97%), of which extranodal marginal zone B-cell lymphoma (EMZL) (59%) is the most common subtype, followed by diffuse large B-cell lymphoma (23%), follicular lymphoma (9%), and mantle cell lymphoma (5%). Orbital lymphoma is primarily a disease of the elderly. Gender distribution varies according to lymphoma subtype. However, extranodal marginal zone B-cell lymphoma (53%) and follicular lymphoma (75%) show a female predominance, whereas diffuse large B-cell lymphoma shows an even gender distribution. Mantle cell lymphoma has a striking male predominance of 80%. The histopathological subtype and the clinical stage of the disease are the best indicators of prognosis and patient outcome. Low-grade lymphomas such as extranodal marginal zone B-cell lymphoma and FL have a good prognosis, whereas high-grade lymphomas (diffuse large B-cell lymphoma and mantle cell lymphoma) are associated with a poor prognosis. When managing solitary low-grade lymphomas, radiotherapy is the treatment of choice. Chemotherapy, with or without radiotherapy, should be chosen for disseminated and high-grade lymphomas.

Blastic Transformation of a Mantle Cell Lymphoma Presenting as an Enlarging Unilateral Orbital Mass

Mantle cell lymphoma (MCL) is an uncommon form of non-Hodgkin lymphoma predominantly affecting male individuals of advanced age. Approximately 1-9% of cases of lymphoma affecting the orbital and ocular adnexal regions are attributed to MCL. We describe the case of a 65-year-old man with a 24-year history of MCL with initial remission followed by multiple relapses who presented with acute-onset binocular diplopia and proptosis of the left eye. Subsequent imaging demonstrated a new left superior orbital mass. Biopsy of the mass revealed two clonally related, yet distinct cellular components demonstrating the classical mantle cell morphology and large cells that appeared to have transformed to the blastoid variant of MCL. Transformation of classical MCL to the blastoid variant of MCL is rare, with few reports in the literature. The blastoid variant of MCL tends to be aggressive and associated with a poor prognosis. The case we describe represents perhaps the first report of MCL transformation observed in the orbit.