Bilateral Primary Non-Hodgkin's Lymphoma of the Lacrimal Sac: A Case Report.

Primary non-Hodgkin's lymphoma of the lacrimal sac is extremely rare, usually representing secondary involvement of systemic malignancy. We report a case of bilateral primary non-Hodgkin's lymphoma of the lacrimal sac presenting with bilateral medial canthal swelling for one month which was preceded by a history of chronic bilateral epiphora and a recurrent history of dacryocystitis. The symptoms partially responded to systemic antibiotics for the past three years. Clinical examination revealed bilateral diffuse erythematous medial canthal swelling extending to the upper cheeks. CT of the orbits and paranasal sinuses demonstrated soft tissue masses involving bilateral lacrimal sacs and ducts. Endoscopic dacryocystorhinostomy (DCR) with excision biopsy of both lacrimal sac was performed and histopathologically confirmed the diagnosis of extranodal marginal zone B-cell lymphoma. She completed six cycles of chemotherapy. The symptoms subsided and radiologically showed a significant reduction of soft tissue mass at bilateral nasolacrimal sacs and ducts after completion of chemotherapy. Recurrent atypical presentation of dacryocystitis with suboptimal response to standard treatment should raise a suspicion of secondary cause. Histopathological examination is therefore crucial to avoid delays in diagnosis and treatment.