Papillary thyroid carcinoma in Mexican patients: clinical aspects and prognostic factors.

The present study characterizes papillary thyroid carcinoma (PTC) in a Mexican patient sample and evaluates potential prognostic factors for recurrence. Clinical records of 229 patients with PTC were analyzed. Surgical specimens were rereviewed and DNA ploidy determined. Cox logistic regression was used to explore prognostic factors. Mean age +/- SD of the patients was 42 +/- 16 years, with a male/female ratio of 24:205. A thyroid mass was the initial manifestation in 99%. Extrathyroid invasion occurred in 45% and nodal metastases in 38%. Mean size +/- SD of the tumors was 3 +/- 2 cm. By flow cytometry 88% of the tumors were DNA euploid and 12% aneuploid. Complete tumor resection was achieved in 83% with an operative mortality of 0.4%. Postoperative hormone suppression was administered in 65% and remnant 131I thyroid ablation in 84%. The 10-year recurrence-free survival was 85%. In the group of patients with tumors totally removed and without distant metastases, none of the 14 evaluated variables demonstrated statistical significance as an independent prognostic factor for recurrence. However, the group of patients in whom a combination of the following factors was present--age > or = 40 years, tumor size > or = 3 cm, local invasion, and lymph node metastases--showed a higher incidence of tumor recurrence.