Treatment of Conjunctival Lymphomas by Beta-Ray Brachytherapy Using a Strontium-90–Yttrium-90 Applicator

We reviewed the outcome of the 10 patients (13 eyes) with localized, biopsy-proven, low-grade lymphoma of the conjunctiva treated at our Department between 1988 and 1997. All patients were treated by β-ray brachytherapy using a bidirectional 90Sr–90Y ophthalmic applicator (Applicator SIA2, Amersham plc).Total doses, prescribed at the surface of the applicator, varied between 40Gy and 80Gy. With a median follow-up of 78 months (range: 14 to 146 months), seven patients remained with no evidence of relapse (67.5% 10 year disease free survival). Local control was achieved in 10 out of 13 eyes (76.9%). Two of the three local relapses were marginal. One of these three patients also developed a metachronous lymphoma in the contralateral conjunctiva. These three patients underwent a second course of brachytherapy with 90Sr/90Y and remained free of second relapse 109, 68 and 33 months after salvage therapy. No cases of systemic relapse were observed. Late (LENT-SOMA) complications were of grade 2 in five eyes, of grade 3 in one eye and of grade 4 in one eye. Late complications of grade 2 or higher were observed in one out of five patients (20%) treated with doses lower or equal to 50Gy and in six out of eight patients (75%) treated with doses higher than 50Gy (P=0.086). Our data indicates that β-ray brachytherapy was ultimately able to control most conjunctival lymphomas but carried a risk of late complications and marginal relapses that was possibly higher than the rates reported for other radiotherapy techniques. Copyright 2002 The Royal College of Radiologists. Published by Elsevier Science Ltd. All rights reserved.