Metastatic differentiated thyroid carcinoma: clinical management and outcome of disease in patients with initial and late distant metastases.

OBJECTIVE: Our objective was to analyze the clinical management and the outcome of disease in differentiated thyroid carcinoma with initial and late distant metastases (M1). PATIENTS AND METHODS: Radioiodine (131I) therapy was applied in 77 differentiated thyroid carcinoma patients with M1 (31 patients with M1-initial and 46 patients with M1-late). The median follow-up of patients was 72.7 months. Probability of disease-specific survival (DSS) was analyzed by the Kaplan-Meier method and the log rank test, while the significance of differences between groups was calculated by the t-test of proportions. RESULTS: Follicular carcinomas were more frequent in patients with M1-late (P<0.05). During the follow-up, 58% of the patients died: 39% of cases had disease related deaths, while 42% had complete remission of disease. Stable disease and progressive disease were significantly influenced by age only (P = 0.0122), while 131I uptake, histological type, and sex had no influence (P = 0.1235; P = 0.340; P = 0.8540, respectively). Remission of disease (complete and partial) was not significantly influenced by age, sex, histological type, and 131I accumulation (P = 0.0644; P = 0.8452; P = 0.6308; P = 0.7675, respectively). DSS in patients with M1-initial and M1-late at 5 years was 71 and 50%, respectively and 62 and 41% at 10 years, respectively, without significant difference (P = 0.2582). Disease related deaths appeared more frequent in patients at 45 years of age or older, significantly caused by distant metastases (P<0.001). CONCLUSION: Distant metastases occur late more often in patients with follicular carcinoma while M1-initial is detected more often in patients with papillary carcinoma. DSS was not significantly different among patients with M1-initial and M1-late. The risk of death from M1 increased after the age of 45 years.

The importance of age over radioiodine avidity as a prognostic factor in differentiated thyroid carcinoma with distant metastases.

BACKGROUND: Differentiated thyroid carcinoma (DTC) usually has a good prognosis and rarely develops distant metastases. Although it might be expected that avid radioiodine uptake in distant metastases would be associated with a favorable outcome, there are few long-term studies regarding this. The present study was performed to evaluate the influence of radioiodine uptake in distant metastases on the disease-specific survival (DSS) in DTC patients. METHODS: This retrospective study included 77 DTC patients with distant metastases (M1) who were treated with (131)I therapy from 1977 to the end of 2000 in our institution. The median follow-up of patients was 6.1 years. Univariate and multivariate analysis were performed using the Kaplan-Meier method and log rank test, and Cox Regression model, respectively. RESULTS: Seventy-seven patients with M1 included 51 (66.2%) women and 26 (33.8%) men; 32 (41.6%) patients were <45 years old and 45 (58.4%) patients were >or=45 years old (range: 8-70 years; mean age: 45.4 years); histologically, there were 54 (70.1%) papillary carcinomas, 22 (28.6%) follicular carcinomas, and one case (1.3%) with an inconclusive histological report. The probability of DSS after appearance of M1 was 57.95% after 5 years, 48.31% after 10 years, and 39.46% after 15 and 20 years. In patients with iodine-avid distant metastases the 5-year DSS was 66.54%, the 10-year DSS was 55.09%, and the 15- and 20-year DSS were 44.99%. In contrast, patients with non-iodine-avid lesions had a 5- and 10-year DSS of 18.33%. This difference relating to the relationship between (131)I uptake in distant metastases and survival was significant (p = 0.0006). The proportion of patients with non-iodine-avid distant metastases that were >or=45 years old was significantly greater than the proportion of patients with non-iodine-avid distant metastases that were <45 years old (p < 0.01). If patients were matched for age, iodine non-avidity significantly shortened the survival in patients <45 years old (p < 0.001). According to multivariate analysis age had significantly greater influence on survival compared with iodine avidity (p < 0.001, p = 0.078, respectively). CONCLUSION: Patients with distant metastases have a long-term survival that depends, in addition to other factors, on age and the degree of radioiodine uptake in distant metastases.

Differentiated thyroid carcinoma with distant metastases: probability of survival and its predicting factors.

The purpose was to analyze survival and its predicting factors in differentiated thyroid carcinoma (DTC) patients with distant metastases (M1). Radioiodine ((131)I) therapy was performed in 363 DTC patients from 1977 to 2000. Among 75 patients, 44 patients had M1 at the time of initial therapy and 31 patients had M1, which developed during the follow up. The probability of survival and its predicting factors were tested by Kaplan-Meier's method. Seventy five DTC patients with M1 included 49 (65.3%) women and 26 (34.7%) men; 30 (40%) patients were < 45 years old and 45 (60%) patients were >or= 45 years old (range 8-70 years; mean age = 45.5 years); 52 papillary carcinomas, 22 follicular carcinomas, and one inconclusive finding. Probability of survival after appearance of M1 was 60.7% at 5 years, 51.2% at 10, and 38.4% at 15 and 20 years. Some predicting factors showed significant influence on the survival: age (p = 0.0001), histological type (p = 0.0138), and initial therapy (p = 0.0351), while gender had no influence (p = 0.2046). We can conclude that patients' age, histopathology of the tumor, and initial therapy significantly influence the survival. Longer survival of DTC patients with M1 could be achieved by adequate surgery followed by 131I therapy.