Metastatic papillary carcinoma of the thyroid: the significance of extranodal extension.

A retrospective study of patients with papillary carcinoma of the thyroid was conducted at The University of Texas M. D. Anderson Cancer Center to determine the significance of cervical nodal metastases in which the cancer has extended beyond the capsule of the node. The survival of 25 patients with extracapsular invasion was compared to 63 controls. There was no statistically significant difference in regional recurrence, distant metastases, death from cancer, or recurrence-free survival between the two groups. Surgically resectable extrathyroid extension of tumor at the primary site and the clinical stage of cervical metastases also had no prognostic significance. The most important prognostic factors for differentiated thyroid carcinoma remain the age and sex of the patient, the histology of the cancer, and the presence of distant metastatic disease.