The percentage of serum thyroglobulin rise in the first-week did not predict the eventual success of high-intensity focussed ablation (HIFU) for benign thyroid nodules

Figures & data

Table 1. Baseline characteristics, treatment parameters, efficacy and complications after single-session high intensity focussed ultrasound.

Variable	Cohort (n = 76)
Age at treatment (years)	50.9 ± 11.5
Sex (male:female)	12:64
Body mass index (kg/m^2)	23.2 ± 4.2
Largest nodule diameter (cm)	3.5 ± 1.2
Nodule volume^a (cm^3)	15.3 ± 9.1
Serum TSH (mIU/L)	1.2 ± 1.0
Serum free T4 (pmol/L)	16.3 ± 2.4
Serum thyroglobulin (ng/mL)	292.8 ± 672.7
Anti-thyroglobulin autoantibody (IU/mL)	64.0 ± 5.9
Anti-TPO autoantibody (IU/mL)	202.0 ± 574.9
Treatment parameters
Total energy delivered (kJ)	14.4 ± 6.1
Total “on-beam” time (min)	63.9 ± 26.6
Treatment time (min)	71.4 ± 26.7
Mean power per voxel (J)	287.1 ± 37.6
Efficacy/volume reduction ratio
3-month (%)	48.4 ± 22.8
6-month (%)	62.2 ± 25.0
≥50% shrinkage at 6-month (%)	59 (76.6)
Complications (%)
Skin burn	0 (0.0)
Vocal cord paresis	3 (3.9)
Hypothyroidism	1 (1.3)

Continuous variables are expressed in mean ± standard deviation. TSH: thyroid stimulating hormone; Tg: thyroglobulin; TPO: thyroid peroxidase.

^a Nodule volume at baseline = (width × depth × length) × (π/6), where π was taken as 3.14159.

Figure 1. Two box plots with one showing the serum thyroglobulin (Tg) on the day of treatment (baseline) and the other showing Tg 4 d after single-session high-intensity focussed ultrasound treatment (first-week).

Table 2. Bivariate spearman’s correlations between percentage change in serum thyroglobulin (Tg) during the first week and baseline characteristics, treatment parameters and efficacy after single-session high intensity focussed ultrasound (HIFU) ablation.

Variable	Baseline serum Tg	Serum Tg in the first week	% Tg change in first week
Age at treatment (years)
Correlation coefficient	0.166	0.049	0.399
Significance (2-tailed)	0.226	0.857	0.126
Body mass index (kg/m^2)
Correlation coefficient	0.190	−0.321	−0.408
Significance (2-tailed)	0.157	0.180	0.083
Largest nodule diameter (cm)
Correlation coefficient	0.372	0.174	−0.151
Significance (2-tailed)	0.007	0.489	0.550
Nodule volume^a (cm^3)
Correlation coefficient	0.322	−0.039	−0.098
Significance (2-tailed)	0.020	0.876	0.699
Serum TSH (mIU/L)
Correlation coefficient	−0.104	−0.202	0.143
Significance (2-tailed)	0.436	0.407	0.559
Serum free T4 (pmol/L)
Correlation coefficient	0.078	0.361	0.187
Significance (2-tailed)	0.507	0.129	0.443
Anti-Tg autoantibody (IU/mL)
Correlation coefficient	−0.025	−0.324	−0.387
Significance (2-tailed)	0.852	0.175	0.101
Anti-TPO autoantibody (IU/mL)
Correlation coefficient	−0.156	0.248	0.504
Significance (2-tailed)	0.243	0.306	0.108
Total energy delivered (kJ)
Correlation coefficient	0.182	−0.243	−0.368
Significance (2-tailed)	0.192	0.315	0.121
Total “on-beam” time (minutes)
Correlation coefficient	0.273	0.112	−0.516
Significance (2-tailed)	0.035	0.648	0.325
Mean power per voxel (J)
Correlation coefficient	0.101	0.133	0.377
Significance (2-tailed)	0.479	0.587	0.112
3-month VRR
Correlation coefficient	−0.208	−0.012	−0.036
Significance (2-tailed)	0.254	0.973	0.920
6-month VRR
Correlation coefficient	0.031	0.144	0.180
Significance (2-tailed)	0.895	0.758	0.699

TPO: thyroid peroxidase; VRR: volume reduction ratio.

Bold signifies statical significance (p value <0.05).