Expression of ICAM-1 in distant metastatic thyroid carcinoma

Distant metastasis from follicular thyroid carcinoma developed in a 48-year-old woman 11 yr after the resection of the primary tumor. Distant metastasis consisted in invasion of the left infraspinatus muscle by malignant thyroid cells. After its surgical removal, in the following 6-8 months multiple metastasis to distant skeletal muscle and brain appeared, and despite chemotherapy and local radiotherapy, the patient finally died. Intercellular adhesion molecule-1 (ICAM-1), a single chain transmembrane glycoprotein, was detected on the surface of cells of the metastatic tissue. Although ICAM-1-positive staining has been recently described in primary tumors such as papillary adenocarcinoma, and metastatic tumors from skin, brain, thymus, liver, adrenal gland and prostate, to our knowledge its expression on distant metastasis from thyroid carcinoma has not been previously reported.