Orbital mass as the presenting symptom of diffuse large B-cell lymphoma causing spontaneous tumor lysis syndrome and rapid multisystem organ failure.

A 68-year-old male presented with a one-month history of progressive proptosis and vision loss in the left eye. Examination of the left eye showed visual acuity of NLP, marked relative proptosis of 10 mm, and complete external ophthalmoplegia. CT orbits showed an extensive left orbital lesion with proptosis. Urgent orbital biopsy was undertaken. Intraoperatively, the patient developed new atrial flutter and fever. Bloodwork revealed metabolic derangements suggestive of tumor lysis syndrome. Systemic evaluation revealed a large tumor burden involving the retroperitoneal space. Histopathology of the orbital specimen showed non-germinal center diffuse large B-cell lymphoma. The patient passed away 3 days postoperatively due to rapidly progressive multisystem organ failure. Our case demonstrates an unusually aggressive presentation of DLBCL in which orbital mass was the first presentation of spontaneous tumor lysis syndrome owing to large systemic tumor burden.