NON-AUTOIMMUNE HYPERTHYROIDISM ASSOCIATED WITH ISOLATED BILATERAL OCULAR LYMPHOMA MIMICKING GRAVES-DISEASE WITH OPHTHALMOPATHY - A CAUSE OFMISDIAGNOSIS

A very rare association of non-autoimmmune hyperthyroidism due to nodu lar goiter with isolated bilateral non-Hodgkin's ocular lymphoma is de scribed. A 66-year-old woman presented with bilateral proptosis, marke d periocular swelling, conjunctival hyperemia and chemosis, severe ext raocular muscle impairment with diplopia. Thyroid function tests showe d normal free thyroid hormone concentrations with undetectable serum t hyrotropin levels. Patient was placed on antithyroid drug treatment, o cular conditions deteriorated. More than two years later, when first s een in our Institution, orbital CT scan showed the presence of a retro -ocular mass that, at biopsy, proved to be B-cell non-Hodgkin's lympho ma, apparently with no localization in other sites. Thyroid evaluation revealed subclinical hyperthyroidism due to an autonomous thyroid nod ule in the left lobe of the gland. Radiotherapy of the orbit was follo wed by a dramatic regression of lymphoma, but further staging some mon ths later showed involvement of several abdominal lymph node structure s. This case underscores the need of a thorough diagnostic work-up of ocular disease resembling Graves' ophthalmopathy, even when it is bila teral and associated with overt or subclinical hyperthyroidism.