A Rare Case of Bilateral Proptosis

A 65-year-old man presented with a 2-year history of severe bilateral proptosis, palpable lymphadenopathy and moderate hepatosplenomegaly. A blood test was positive for hepatitis C infection. CT showed palpebral infiltrative lesions with regional progression through the temporal and masticatory spaces to the pharynx and hypopharynx causing almost complete airway obstruction. A palpebral biopsy was consistent with low-grade Bcl-2+ extra-nodal MALT non-Hodgkin B-cell lymphoma. The patient received six cycles of rituximab-based chemotherapy with clinical remission at 9-month follow-up. Bilateral proptosis is a rare presentation of several diseases. When brain CT excludes cavernous sinus pathology, thyroid ophthalmopathy or haematological malignancy should be considered. LEARNING POINTS: Bilateral proptosis is a rare presentation with a broad differential diagnosis, and is most frequently is caused by cavernous sinus disease, thyroid ophthalmopathy or haematological malignancy. Hepatitis C may be associated with MALT lymphoma and presents mainly at non-gastric locations even with few hepatic manifestations of the infection. Long-term low-grade lymphoma may present with severe disseminated disease at diagnosis, but treatment response is generally good.