SCLEROTHERAPY WITH OK-432 FOR RECURRENT CYSTIC THYROID-NODULE

We have adopted OK-432 as a sclerosing agent in the treatment of cysti c predominant thyroid nodules and have analyzed our findings to assess the efficacy of intralesional instillation of OK-432. From 1992 throu gh 1993, 48 patients with recurrent or progressive cystic thyroid nodu les after 2 or 3 aspirations alone, and whom were cytologically negati ve for malignancy, were used for this study. The OK-432 solution was p repared by dissolving 0.1 mg of OK-432 in 2 mi of physiologic saline a nd it was instilled in the amount of 1/10-to-1/5 of the aspirated cyst ic fluid. A repeated course of therapy was given up to 3 times when su fficient resolution was not obtained 4-to-6 weeks after treatment. The mean number of treatment sessions per patient was 1.5. Throughout the follow-up period from 30-to-45 months (mean, 38 months), 32 (66.7%) p atients experienced an almost complete disappearance (<0.5 cm in diame ter) of the cystic lesion, and 12 (25%) patients responded partially b y having it decrease by more than half (>0.5 cm in diameter) of the in itial cyst size, and none of these patients required further treatment . The remaining 4 (8.3%) patients showed insufficient resolution despi te 3 courses of therapy and 2 of these patients underwent thyroidectom y, in which the lesion proved benign in both cases. All of the patient s tolerated the sclerotherapy well. No significant focal complications attributed to this treatment were observed. However, a low-grade feve r was observed in 26 (54.2%) patients for 2 to 5 days after instillati on, which subsided with symptomatic treatment On the basis of our expe rience, OK-432 sclerotherapy appears to be safe, simple and effective, and can be a useful alternative treatment for cystic thyroid nodules.