Thyroid Nodules, Cold

Definition and Characteristics

The term cold nodule indicates that this thyroid lesion shows reduced technetium uptake compared with normal thyroid tissue on scintiscan [1] (Fig. 1).
Thyroid Nodules, Cold. Figure 1
The lack of scintigraphic Technetium uptake in CTNs correlates with a lack of NIS cell membrane insertion, (a) Scintigraphy, (b) NIS localized in the cell membrane of hot nodule, (c) NIS localized intracellularly in cold nodule.


Approximately 85% of all thyroid nodules are cold thyroid nodules (CTNs) [1]. The large majority of them are benign and ∼5% of all nodules are malignant [2]. The prevalence may vary geographically with iodine supply.


In agreement with the decreased scintigraphic uptake, a defective cell membrane targeting of NIS has been reported for CTNs [3]. Moreover, a markedly increased proliferation, increased expression of histone mRNAs and cell cycle-associated genes like cyclin D1, cyclin H/cyclin depende...