Prognostic factors in differentiated thyroid carcinoma: a multivariate analysis of 234 consecutive patients

BACKGROUND AND OBJECTIVES: The clinical characteristics and patient outcome of a group of patients treated for differentiated thyroid carcinoma (DTC) were analyzed in order to assess the relative influence of different prognostic factors. MATERIALS AND METHODS: We retrospectively reviewed data about sex, age, size and histologic behavior of the tumor, extrathyroid extension of the tumor, lymph node status, distant metastasis at diagnosis, surgical procedures, and overall survival from 234 patients treated for DTC. Data were submitted to a statistical analysis. RESULTS: Using a univariate analysis, we found that survival rates were significantly influenced by age (P = 0.0001), size (P = 0.018), extrathyroidal extension (P = 0.000001), lymph node involvement (P = 0.03), and distant metastases (P = 0.049). Age and size were independent prognostic factors at multivariate analysis (t = 2.694 and t = 2.443, respectively). CONCLUSIONS: On the basis of our results and of a review of the literature, we conclude that total thyroidectomy is the treatment of choice in DTC, except for small (<1 cm) papillary carcinoma, that could be treated by lobectomy plus isthmectomy, while lymphadenectomy is indicated only in case of macroscopic involvement.