Cryotherapy for the treatment of small growing choroidal melanomas

Purpose. To evaluate the effectiveness and toxicity of cryotherapy in treating enlarging choroidal melanomas. Methods. Four eyes of four patients with small growing pigmented choroidal tumors have been treated with cryotherapy to destroy the tumors. The thickness of the treated tumors were 3.8, 1.76, 1.7, and 3.2 mm; the maximal basal diameters were 17, 7.5, 11.4, and 10.75 mm, respectively. All tumors were treated with a triple freeze thaw technique using a conventional retinal cryoprobe. Three patients were treated on two occasions to destroy persitent areas of tumor. Results. Three patients have no evidence of residual tumor ophthalmoscopically or by echography 7 months,and 2.25 and 3 years after their last cryotherapy treatment. One patient died from complications of diabetes mellitus 18 months after her initial session of cryotherapy. Prior to her death the tumor appeared to have responded well. The patient with the largest tumor (3.8 mm in thickness, and 17 mm in basal diameter) developed a persistent, total exudative retinal detachment following cryotherapy. The eye was enucleated 13 months following cryotherapy. Histopathologic study of the enucleated eye revealed in some areas the tumor had been completely destroyed, while in other areas there were still thin areas of viable tumor cells present. Conclusions. Our early results with cryotherapy for the treatment of growing melanomas suggests cryotherapy may be an effective modality for treating small growing choroidal melanomas. It is superior to laser in that it treats the full thickness of the tumor, and unlike radiation it may be administered on multiple occasions to treat persistent or residual tumor.