Does postoperative thyrotropin suppression therapy truly decrease recurrence in papillary thyroid carcinoma? A randomized controlled trial.
ABSTRACT TSH suppression therapy has been used to decrease thyroid cancer recurrence. However, validation of effects through studies providing a high level of evidence has been lacking.
This single-center, open-label, randomized controlled trial tested the hypothesis that disease-free survival (DFS) for papillary thyroid carcinoma (PTC) in patients without TSH suppression is not inferior to that in patients with TSH suppression.
Participants were randomly assigned to receive postoperative TSH suppression therapy (group A) or not (group B). Before assignment, patients were stratified into groups with low- and high-risk PTC according to the AMES (age, metastasis, extension, size) risk-group classification.
For patients assigned to group A, L-T(4) was administered to keep serum TSH levels below 0.01 μU/ml. TSH levels were adjusted to within normal ranges for patients assigned to group B. Recurrence was evaluated by neck ultrasonography and chest computed tomography.
Eligible participants were recruited from 1996-2005, with 218 patients assigned to group A and 215 patients to group B. Analysis was performed on an intention-to-treat basis. DFS did not differ significantly between groups. The 95% confidence interval of the hazard ratio for recurrence was 0.85-1.27 according to Cox proportional hazard modeling, within the margin of 2.12 required to declare 10% noninferiority.
DFS for patients without TSH suppression was not inferior by more than 10% to DFS for patients with TSH suppression. Thyroid-conserving surgery without TSH suppression should be considered for patients with low-risk PTC to avoid potential adverse effects of TSH suppression.
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ABSTRACT: Background. We retrospectively analyzed whether poor differentiation is the independent prognostic factor for thyroid carcinoma or not. Methods. The subjects were 29 patients with PDTC who were treated between April 1996 and March 2006 to compare with those of well-differentiated papillary carcinoma patients (n = 227). Results. The relapse free (RFS), distant relapse-free survival and cause-specific survival, rates were significantly lower in patients with PDTC (P < .0001, P < .001, and P < .05). After classification into focal (<10%) and diffuse type (over 10%) of PDTC, there were no significant differences in RFS and cause-specific survival due to component type or proportion of poorly differentiated component. On multivariate analysis, poor differentiation (P < .0005, RR = 4.456, 95% CI; 1.953-10.167) and extrathyroidal infiltration (P < .05, RR = 2.898, 95% CI; 1.278-6.572) showed a significant impact on DFS, and poor differentiation (P < .05, RR = 9.343, 1.314-66.453) and age (P < .005, RR = 1.306, 1.103-1.547) significantly impacted cause-specific survival. Conclusion. Poor differentiation was an independent factor for survival. Distant relapse was significantly more common among PDTC patients, and systemic therapy might be warranted.ISRN endocrinology. 01/2011; 2011:308029.