MALT Lymphoma Masquerading as Thyroid Orbitopathy (.pdf)

67 y/o WF referred for disc edema OS, complaining of distortion OS x 1 year. No headaches. PMH: hypertension and hypothyroidism. SH: 40 pack-years of smoking. Exam revealed 20/20 and 20/25. Visual fields were FTC, and color vision was normal. Pupils: 1+ reaction OU, and no RAPD. EOM revealed mild limitations. Exam demonstrated RLL and LLL edema, bilateral brow ptosis, bilateral Queen Anne sign, and lid retraction with an MRD of 6 mm OU. Hertel was 20 and 22 with a base of 97. DFE OS revealed 2+ disc edema. TED with compressive optic neuropathy OS was suspected. CT revealed bilateral apical orbital soft tissue masses with widening of the superior orbital fissures bilaterally and extension on the left side into the left pterygopalatine fossa and along branches of the left trigeminal nerve. MRI further characterized the masses limited to the posterior third of the orbits R>L, bilateral infiltration of the adjacent tendons of the EOMs with infiltration into the muscle bellies on the right, and extension along the left petrous ridge and left free edge of the tentorium. Left upper cervical adenopathy was identified by imaging and then biopsied by ENT. Results revealed a low-grade marginal zone lymphoma (MALToma) composed of CD20+ B-cells with abnormal coexpression of BCL2. Concurrent flow cytometry identified a population of CD5-/CD10- kappa light chain restricted B-cell population. CT chest, abdomen, and pelvis was unremarkable.