To the Editor.
—Having aspirated cystic thyroid nodules since 1965, and sclerosed carefully selected nodules with 3% sodium tetradecyl sulfate since 1973,1 we welcomed the observations of Treece et al2 and Ryan3 in the December Archives. For readers who wish to use this excellent therapeutic modality we offer the following caveats.
The authors stated that all cysts had no solid component by ultrasonography or after complete evacuation of the cyst cavity. The rebleeding in their failures suggests to us that part of the original lesion remained. It is unlikely that the recurrent hemorrhage in all of the authors' nodules came from an endothelial or fibrous, tissue-lined cyst. Perhaps the ultrasound studies used would not resolve the small remnants.
Because we have encountered cancers as the tissue remnant of "totally" cystic nodules,1 we limit the use of sclerosing agents to nodules for which we have a cytological or