Distant Metastases in Differentiated Thyroid Cancer: Long-term Results of Radioiodine Treatment and Statistical Analysis of Prognostic Factors in 214 Patients

Abstract

Long-term results and statistical analysis of prognostic factors in a series of 214 patients with distant metastases from differentiated thyroid cancer (DTC) are reported here. These 214 were part of a total series of 1457 patients with DTC referred to our center from 1967 to 1987. All patients underwent surgery and 131-I therapy and were treated with TSH suppressive doses of thyroid hormones. After a mean follow-up of 7.3 years including clinical, scintigraphic, radiological and laboratory investigations, 24.4% of patients were alive without disease, 36.5% alive with disease, 1.8% dead without disease and 37.3% dead with disease. One of the main factors influencing the survival in our series was 131-I uptake (RIU) by metastatic tissue. No case of complete remission of disease was observed among patients with nonfunctioning metastases. Another important factor was the site of metastases, patients with bone metastases having the worst prognosis. The patient's age at diagnosis represented another important factor for survival; patients over 40 years, particularly those over 60 years had a bad prognosis. A clear interrelation was found among the factors advanced age, nonfunctioning metastases and bone metastases. Patients with these last clinical features were considered to be at high risk and generally had a fatal outcome. Another significant prognostic factor revealed by univariate analysis was the histologic type. Patients with follicular tumor showed a poorer prognosis in comparison to papillary tumor. When multivariate analysis was applied, the factors age at diagnosis, site of metastases and RIU proved to have a significant influence on survival, but not the histologic type. Lastly, the relative rate of males was higher in the group of patients with metastases in comparison to the whole series of DTC patients. Despite this, the factor sex did not influence survival.

Clinical Features of Bone Metastases Resulting from Thyroid Cancer: A Review of 28 Patients over a 20-year Period

“…Multisite metastasis is generally considered to be associated with decreased survival, and limited extent of metastatic disease is a favorable factor for survival [7,15], although Pittas et al reported that the survival in patients who had a single bone lesion was not better than in those with multiple bone lesions [14]. Age is considered as a prognostic factor of improved survival [24,25], but in our study, age at diagnosis of bone metastasis was not statistically significant, maybe due to the small number of patients less than 45 years old (not described in above results). Early detection could initiate prompt therapy and improve survival.…”

Factors affecting survival in 43 consecutive patients after surgery for spinal metastases from thyroid carcinoma

“…The levels above and below the vertebrectomy site were counted as parts of the anterior column construct when plating, Steinmann pins, or chest tube insertion were involved. Fourteen patients did not require posterolateral stabilization; of those who did, the median length of the construct was 6 vertebral levels (range [3][4][5][6][7][8][9][10][11][12][13][14]. Two patients underwent lumbopelvic or lumbosacropelvic fixation; in these instances, the sacrum or pelvis was treated as 1 level.…”

“…15,24,26 Prior studies have assessed the prognostic factors associated with systemic metastasis from thyroid carcinoma; however, none have specifically investigated the factors that affect survival in patients undergoing surgery for spinal metastases. 3,5,13,16,18,21,25,32,36,39,40 Therefore, the objective of this study was to analyze a series of consecutive patients who underwent surgery for spinal metastasis from thyroid cancer in order to identify factors associated with postoperative survival and complications. This prognostic information may aid in clinical decision making, as patients with a more favorable prognosis may warrant more aggressive intervention and patients with poor life expectancy may be spared from aggressive surgery.…”

Pulmonary metastases in differentiated thyroid cancer: efficacy of radioiodine therapy and prognostic factors

“…Distant metastases are an uncommon event in DTC and a wide range in prevalence (4-23%) has been reported (1,2,3,4,5,6). Lungs are the most frequent site of distant metastasis in DTC and the resulting respiratory failure may be the most common cause of death.…”