Orbital marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue with amyloidosis: a case series and review of the literature

Abstract Objectives Orbital mucosa-associated lymphoid tissue (MALT) lymphoma with amyloidosis is an uncommon condition. This study presents three cases of this rare disease, to provide insights into its clinical manifestation, clinicopathological features, treatment options, and prognosis. Case presentation This study reports three cases of orbital MALT lymphoma with amyloidosis. All patients exhibited proptosis, and imaging findings revealed orbital masses. Furthermore, two cases were potentially associated with IgG4-related ophthalmic disease. The diagnosis of all patients was confirmed via immunohistochemical (IHC) analysis of the biopsy samples. One patient exhibited space-occupying lesions in the lungs and kidneys. In addition, one patient underwent orbital radiotherapy, and a 1-year follow-up revealed a reduction in the orbital mass volume. Another patient underwent systemic chemotherapy, but imaging at the eight-month follow-up revealed no substantial changes in the orbital or systemic lesions. Conclusions The coexistence of orbital MALT lymphoma and amyloidosis presents diagnostic challenges because of its rarity and the involvement of two distinct conditions. Immunohistochemistry (IHC) is a key tool for establishing a definitive diagnosis. Surgery is the most commonly employed treatment method. Although it does not provide a definitive cure, the primary importance lies in obtaining biopsy samples for precise diagnosis and reducing the tumor burden to alleviate the mass effects. Orbital radiotherapy remains a key treatment option. However, in cases with systemic involvement, systemic chemotherapy or alternative therapies may be prioritized to manage systemic symptoms effectively.