[Sclerotherapy of thyroid cysts with tetracycline hydrochloride]

In order to verify sclerotherapy efficiency in solitary thyroid cysts, needle aspiration of the cyst followed by instillation of tetracycline hydrochloride into the cyst cavity was performed in 110 patients; in thirty of these the aspirations was ultrasonically guided. A tight dressing on the neck was applied for 48 hours in order to maintain pressure on the cyst cavity. All patients were treated with L-T4 in TSH-suppressive doses. In a few patients (< 155), the tetracycline instillation caused local pain, lasting less than two hours. In no case, did cytological examination of the sediment of the aspirated fluid reveal any evidence of malignant cells. In 82 patients (84.54% of the 97 controlled patients), the last ultrasonic follow-up (performed at 3, 6, 9, 12 or 24 months) showed a decrease in lesion size. In particular, 16 patients (16.50%) had a complete cyst disappearance, 41 patients (42.17%) had a volume reduction of the cyst between 85 and 65%, and in 25 patients (25.77%) the reduction was more than 25%. In the remaining 15 patients (15.46%) a second treatment was performed, 3 of them also required a third treatment but in all these cases, the results seemed to be less satisfactory. The distinction in cyst size seemed to indicate that in the case of a large cyst (> 36 mm diameter), the treatment gives better results (92% success rate against 82% of the other patients). In conclusion, we are able to affirm that needle aspiration of the thyroid cyst with instillation of tetracycline hydrochloride is a simple, well tolerated and low cost technique.(ABSTRACT TRUNCATED AT 250 WORDS)