No evidence of thyrotropin receptor and G(S alpha) gene mutation in high iodine uptake thyroid carcinoma

Usually, thyroid carcinoma presents as a cold nodule on radioiodine scintig raphy. High-uptake nodules on iodine thyroid scans are associated with an e xceedingly low incidence of malignancy. Only 29 cases of carcinomas appeari ng as hot or warm nodules have as yet been reported. From 1993 to 1999, we have observed eight similar cases (4 hot and 4 warm thyroid nodules) sugges ting that thyroid carcinomas may not be as rare as usually considered in th ese circumstances. Four tumors were available for molecular analysis on par affin-embedded sections. Because no mutations were found in the whole codin g portions of thyrotropin-receptor (TSH-R) gene and fragments encompassing the mutational hot spots of the Gs alpha gene, it is unlikely that activati ng mutations of the TSH-R or G(s alpha) genes were involved in these carcin omas.