Plaque radiotherapy in recurrent or incomplete-excised conjunctival squamous cell carcinoma and melanoma

Purpos: To assess the results of brachytherapy in patients with recurrent or incomplete excised conjunctival squamous cell carcinoma (SCC) and malignant melanoma. Methods: Three patients underwent brachytherapy of one eye and one patient underwent brachytherapy of both eyes with ruthenium-106 (RU-106) plaques, all of them had a history of incomplete resection or recurrence of the tumor after surgery. All patients were male with an average age at diagnosis of 54 years (range, 34-76 years). The shape and the size of plaques were determined based on location and size of the suspected area. The plaque was inserted to deliver a target dose of 80-100 Gy in the region of conjunctival malignancy. The diagnosis was squamous cell carcinoma in three eyes and conjunctival melanoma in two eyes. All patients had surgical history of one to three previous excisions with or without cryotherapy before brachytherapy. There were microscopic residual tumors after excision in 2 eyes and recurrent lesion was evident in 3 other eyes. A mean dose of 95 Gy was delivered to the tumor bed. Results: Complete tumor regression without any evidence of recurrent lesion was obtained in all five eyes. The patients were followed for 32 months on average (range, 18-42 months). No radiation related complication was detected, with an exception of a dry eye in the last follow up. Conclusion: Brachytherapy with RU-106 plaque is an alternative method for treatment of selected patients with recurrent or residual conjunctival SCC and melanoma.