ICAM1 mRNA expression (n = 147 cases, of which 70 were benign and 77 were malignant) was higher in malignant (0.99 ± 1.413 AU) than in benign thyroid nodules (0.46 ± 0.85 AU, p = 0.0001), and it differentiated PTC from goiter (p = 0.0030). Here, ICAM1 is linked to goiter.