RADIOTHERAPY ALONE FOR SEVERE, PROGRESSIVE THYROID-ASSOCIATED ORBITOPATHY - LONG-TERM RESULTS WITH COMPARISON OF SCORING SYSTEMS

Background Therapeutic results after radiotherapy in thyroid associate d orbitopathy (TAO) often are not comparable, because either different therapeutic methods at the same time or different scores were used in the evaluation. This study focusses on radiotherapy alone by means of different evaluation scores. Patients and methods 60 patients (49 wom en, 11 men) received standard external beam radiotherapy (20 Gy: 10 fr actions of each 2 Gy) as ultima ratio after failing different other th erapies of thyroid associated orbitopathy. The mean interval from begi nning of the symptoms to the radiotherapy was 17 +/- 36 months (betwee n 6 and 240 months). The follow up was documented classified by means of 4 different scores - before radiotherapy, 6-12 weeks, 1 year after radiotherapy and at last follow up. The changes of symptom categories or grades of the different scores were analysed. Results Significant c hanges of the ophthalmic scores were observed when comparing the endpo ints at 6-12 weeks, and at 1-year follow up after radiotherapy, The '' classical'' Werner score at 12 months follow up did not correlate well with the other TAO scores: American thyroid association (ATA) scoring system, Stanford scoring system, International ophthalmopathy index, while all other TAO scores revealed a high correlation among each ethe r. According to the Orbitopathy Index (OI) of Grussendorf an improveme nt from 14.2 points to 6.0 points was achieved. Soft tissue involvemen t and corneal involvement demonstrated the highest response rate (83/8 7%), extraocular muscle involvement and proptosis a good response rate (69/70%). No long-term complications were observed. Conclusion Accord ing to this study there are indications that external beam radiotherap y is a suitable therapy even after pre-treatment and a longer course o f TAO. The OI, the ATA and the Stanford scoring systems lend to simula r results in the assessment of thyroid orbitopathy.