Aim: The prevalence of thyroid orbitopathy, compared with an estimate for the United Kingdom population, is examined in a large cohort of patients treated for periocular lymphoma.
Patients and methods: Clinical details were reviewed for patients presenting to the Orbital Clinic at Moorfields Eye Hospital with biopsy-proven periocular lymphoma. Recorded evidence of prior thyroid gland abnormality or thyroid eye disease was sought and treatment details recorded, together with that of the subsequent periocular lymphoma. The calculated prevalence of thyroid orbitopathy in our patients with periocular lymphoma was compared with an estimate based upon published figures for a United Kingdom population.
Results: Of 369 patients with periocular lymphoma, 20 (5%) had a history of thyroid disease and adequate notes were available in 10 cases: All had autoimmune thyrotoxicosis between 11 and 27 years (median 17.5) before diagnosis of periocular lymphoma and 6/10 had thyroid orbitopathy-none receiving orbital radiotherapy for treatment of their thyroid eye disease. Using a calculated estimate for the UK prevalence of thyroid orbitopathy, the probability of even these six cases of ophthalmopathy among 369 patients with periocular lymphoma is very low (P=0.007).
Conclusion: Compared with a population estimate, patients with periocular lymphoma had a significantly greater prevalence of preceding thyroid orbitopathy, with a median latency of 17 years. Thyroid orbitopathy possibly predisposes to later local lymphoma in a manner similar to the late emergence of lymphoma with other chronic inflammatory diseases-such as Sjögren's syndrome, Hashimoto's thyroiditis, coeliac disease, or Helicobactergastritis.