Orbital radiation therapy for Graves' ophthalmopathy

Thyroid eye disease

Thyroid eye disease (TED) is the most common cause of proptosis in adults, and should always be a consideration in patients with unexplained diplopia, pain, or optic nerve dysfunction. At least 80% of TED is associated with Graves disease (GD), and at least 50% of patients with GD develop clinically evident symptomatic TED. The most confusing patients for doctors of all subspecialties are the patients with eye symptoms and signs that precede serum evidence of a thyroid imbalance. Management of TED may include immunosuppressive medications, radiation, or surgery. Although the prognosis for optic nerve function is excellent, the restrictive dysmotility can result in permanent disability. Orbit and eyelid reconstruction are reserved for stable, inactive patients and are the final steps in minimizing facial alterations and enhancing the patient's daily functioning.

Protocol for the combined immunosuppression & radiotherapy in thyroid eye disease (CIRTED) trial: a multi-centre, double-masked, factorial randomised controlled trial

BACKGROUND

Medical management of thyroid eye disease remains controversial due to a paucity of high quality evidence on long-term treatment outcomes. Glucocorticoids are known to be effective initially but have significant side-effects with long-term use and recrudescence can occur on cessation. Current evidence is conflicting on the efficacy of radiotherapy and non-steroid systemic immunosuppression, and the majority of previous studies have been retrospective, uncontrolled, small or poorly designed.The Combined Immunosuppression and Radiotherapy in Thyroid Eye Disease (CIRTED) trial was designed to investigate the efficacy of radiotherapy and azathioprine in combination with a standard course of oral prednisolone in patients with active thyroid eye disease.

METHODS/DESIGN

Patients with active thyroid eye disease will be randomised to receive (i) azathioprine or oral placebo and (ii) radiotherapy or sham-radiotherapy in this multi-centre, factorial randomised control trial. The primary outcome is improvement in disease severity (assessed using a composite binary measure) at 12 months and secondary end-points include quality of life scores and health economic measures.

DISCUSSION

The CIRTED trial is the first study to evaluate the role of radiotherapy and azathioprine as part of a long-term, combination immunosuppressive treatment regime for Thyroid Eye Disease. It will provide evidence for the role of radiotherapy and prolonged immunosuppression in the management of this condition, as well as pilot data on their use in combination. We have paid particular attention in the trial design to establishing (a) robust placebo controls and masking protocols which are effective and safe for both radiotherapy and the systemic administration of an antiproliferative drug; (b) constructing effective inclusion and exclusion criteria to select for active disease; and (c) selecting pragmatic outcome measures.

TRIAL REGISTRATION

Current controlled trials ISRCTN22471573.