Analysis of risk of death from differentiated thyroid cancer

The records of 231 patients with differentiated thyroid cancer, treated at the University Hospital of Granada between 1972 and 1986, were reviewed to determine which factors were associated with a favourable response and prolonged survival. Radical surgery was the initial treatment in the large majority of the patients. During the postoperative period, 174 patients received 131I therapy and 12 patients were treated by external irradiation. All of them received hormone replacement therapy. Median follow up was over 5 years. Kaplan-Meier actuarial overall survival (S) and disease-free survival (DSF) at 10 years were used as end points for analysis. Survival and freedom from relapse at this time were 0.93 +/- 0.02 and 0.63 +/- 0.06, respectively. No flattening of the relapse curve was observed during the period of follow-up. Univariate analysis showed that the prognosis was significantly influenced by age, sex (papillary cancer only), histological type of tumour, clinical-pathological stage of disease and cervical lymph node status (entire group and papillary cancer). Using Cox's regression model, two groups of patients with low and moderate risk of death and moderate and high risk of recurrence could be identified.