Comparison of efficacy, safety, and patient satisfaction between thermal ablation, conventional/open thyroidectomy, and endoscopic thyroidectomy for symptomatic benign thyroid nodules

Figures & data

Figure 1. Flow chart of patient inclusion and exclusion in this study. BTNs: benign thyroid nodules; TA: thermal ablation; ConT: conventional/open thyroidectomy; ET: endoscopic thyroidectomy.

Table 1. Comparison of baseline characteristics of patients with BTNs who underwent TA and ConT therapy before and after propensity score matching.

Variable	Before propensity matching			After propensity matching
	TA (n = 129)	ConT (n = 320)	p-Value	TA (n = 118)	ConT (n = 118)	p-Value
Sex (female) (%)	111 (86.0)	243 (75.9)	<0.05	100 (84.7)	103 (87.2)	0.573
Age (years)	49.4 ± 14.5 (21–74)	56.4 ± 11.0 (22–79)	<0.001	50.9 ± 14.0 (21–74)	52.5 ± 12.7 (22–78)	0.350
Size of dominant nodule (cm)	3.3 ± 1.2 (1.5–7.9)	3.6 ± 1.3 (1.5–8.7)	<0.05	3.4 ± 1.2 (1.5–7.9)	3.5 ± 1.2 (1.5–8.7)	0.424
Volume of dominant nodule (ml)	12.1 ± 15.3 (0.6–118.7)	15.6 ± 20.0 (0.6–158.5)	0.07	12.1 ± 15.5 (0.6–118.7)	14.1 ± 15.6 (0.7–158.5)	0.380
Symptom score	5 (3–6)	5 (3–6)	0.471	5 (3–6)	5 (3–6)	0.705
Cosmetic score	3 (2–3)	3 (2–4)	0.181	3 (2–3)	3 (2–3)	0.758

BTNs: benign thyroid nodules; TA: thermal ablation; ConT: conventional/open thyroidectomy.

Data are presented as numbers (percentages), mean ± standard deviation (range), or median (interquartile range).

Table 2. Comparison of baseline characteristics of patients with BTNs who underwent TA and ET therapy before and after propensity score matching.

Variable	Before propensity matching			After propensity matching		p-Value
	TA (n = 129)	ET (n = 56)	p-Value	TA (n = 43)	ET (n = 43)
Sex (female)	111 (86.0)	52 (92.9)	0.189	40 (93.0)	39 (90.7)	0.693
Age (years)	49.4 ± 14.5 (21–74)	32.9 ± 8.8 (19–56)	<0.001	38.0 ± 10.4 (21–66)	35.3 ± 8.4 (19–56)	0.197
Size of dominant nodule (cm)	3.3 ± 1.2 (1.5–7.9)	3.2 ± 1.1 (1.5–7.3)	0.362	3.3 ± 1.1 (1.5–6.2)	3.1 ± 1.1 (1.5–7.3)	0.320
Volume of dominant nodule (ml)	12.1 ± 15.3 (0.6–118.7)	9.4 ± 12.8 (0.8–88.7)	0.247	10.2 ± 10.7 (0.8–52.0)	9.4 ± 14.2 (0.8–88.7)	0.767
Symptom score	5 (3–6)	4 (3–5)	0.043	5 (3–6)	4 (3–5)	0.303
Cosmetic score	3 (2–3)	3 (1–4)	0.785	3 (1–4)	2 (1–4)	0.903

BTNs: benign thyroid nodules; TA: thermal ablation; ET: endoscopic thyroidectomy.

Data are presented as numbers (percentages), mean ± standard deviation (range), or median (interquartile range).

Figure 2. Ultrasound images of a 48-year-old woman with a BTN before and after RFA. (A) Before RFA, an ultrasound image reveals a solid mixed echo nodule (arrows), with a nodule volume of 7.06 mL. (B) Before RFA, the nodule shows hyper-enhancement (arrows) on a CEUS image of the early phase. (C) Ultrasound image shows insertion of the needle (short arrows) into the nodule and appearance of a hyperechoic ablation zone during RFA (long arrows). (D). Immediately after RFA, the ablation zone (arrows) shows no enhancement on CEUS images. (E) At 1 month after RFA, the volume of the ablation zone (arrows) is 4.01 mL (VRR = 43.2%). (F) At 1 month after RFA, the ablation zone (arrows) shows no enhancement on CEUS images. (G) At 3 months after RFA, an ultrasound image reveals that the volume of the ablation zone (arrows) has decreased to 2.15 mL (VRR = 69.5%). (H) At 12 months after RFA, the volume of the ablation zone (arrows) has decreased to 0.12 mL (VRR = 98.3%). BTN: benign thyroid nodule; RFA: radiofrequency ablation; VRR: volume reduction ratio; CEUS: contrast-enhanced ultrasound.

Figure 3. Ultrasound images of a 31-year-old woman with a BTN before and after MWA. (A) Before MWA, an ultrasound image reveals a solid iso-echoic nodule (arrows), with a nodule volume of 23.06 mL. (B) Before MWA, the nodule shows hyper-enhancement (arrows) on CEUS images of the early phase. (C) Ultrasound image shows insertion of the needle (arrows) into the nodule and appearance of a hyperechoic ablation zone (arrows) during MWA. (D) Immediately after MWA, the ablation zone (arrows) shows no enhancement on CEUS images. (E) At 1 month after MWA, an ultrasound image reveals that the volume of the ablation zone (arrows) has decreased to 14.93 mL (VRR = 35.3%). (F) At 1 month after RFA, the ablation zone (arrows) shows no enhancement on CEUS images. (G) At 1 year after MWA, an ultrasound image reveals that the volume of the ablation zone (arrows) is 12.16 mL (VRR = 47.2%). (H) At 1.5 years after MWA, the volume of the ablation zone (arrows) is 12.16 mL (VRR = 47.2%). BTN: benign thyroid nodule; MWA: microwave ablation; CEUS: contrast-enhanced ultrasound; VRR: volume reduction ratio.

Table 3. Comparison of treatment outcomes between TA and ConT for BTNs after propensity score matching.

	TA (n = 118)	ConT (n = 118)	P
Treatment time (min)	32.6 ± 8.8 (24–59)	65.8 ± 10.3 (53–98)	<0.001
Days of hospital stay (day)	1.4 ± 0.6 (0–2)	4.0 ± 1.0 (2–8)	<0.001
Direct medical costs (USD)	2509 ± 244 (1952–3267)	3001 ± 579 (1848–6020)	<0.001
Treatment-related complications (%)	4 (3.4)	8 (6.8)	0.236
Post-operative hypothyroidism	1 (0.8)	30 (25.4)	<0.001
Symptom score after surgery	2 (2–2)	2 (1.5–2)	0.826
Cosmetic score after surgery	1 (1–1)	1 (1–1)	0.946

TA: thermal ablation; ConT: conventional/open thyroidectomy; BTNs: benign thyroid nodules.

Data are presented as numbers (percentages), mean ± standard deviation (range), or median (interquartile range).

Table 4. Comparison of treatment outcomes between TA and ET for BTNs after propensity score matching.

	TA (n = 43)	ET (n = 43)	p
Treatment time (min)	29.6 ± 8.0 (21–41)	71.9 ± 10.0 (60–96)	<0.001
Days of hospital stay (day)	0.8 ± 0.6 (0–2)	3.6 ± 1.1 (2–6)	<0.001
Direct medical costs (USD)	2522 ± 443 (2100–4940)	3336 ± 625 (2142–4760)	<0.001
Treatment-related complications (%)	1 (2.3)	0 (0)	1.000
Post-operative hypothyroidism	0 (0)	8 (18.6)	<0.01
Symptom score after surgery	1 (1–2)	1 (0–2)	0.356
Cosmetic score after surgery	1 (1–2)	1 (1–1)	0.196

TA: thermal ablation; ET: endoscopic thyroidectomy; BTNs: benign thyroid nodules.

Data are presented as numbers (percentages), mean ± standard deviation (range), or median (interquartile range).

Table 5. Comparison of patient satisfaction between TA and ConT for BTNs based on a telephone survey.

	TA (n = 118)	ConT (n = 118)	p
Post-operative discomfort (%)			<0.05
Yes	6 (5.1)	16 (13.6)
No	112 (94.9)	102 (86.4)
Symptom relief (%)			0.099
Fully	114 (96.6)	108 (91.5)
Partially	2 (1.7)	5 (4.2)
No	2 (1.7)	5 (4.2)
Cosmetic relief (%)			<0.01
Fully	115 (97.5)	100 (84.7)
Partially	2 (1.7)	8 (6.8)
No	1 (0.8)	10 (8.5)
Post-operative levothyroxine use (%)			<0.001
Yes	1 (0.8)	30 (25.4)
No	117 (99.2)	88 (74.6)
Overall satisfaction (%)			0.114
Fully	107 (90.7)	99 (83.9)
Partially	10 (8.5)	16 (13.6)
No	1 (0.8)	3 (2.5)

TA: thermal ablation; ConT: conventional/open thyroidectomy; BTNs: benign thyroid nodules.

Data are presented as numbers (percentages).

Table 6. Comparison of patient satisfaction between TA and ET for BTNs based on a telephone survey.

	TA (n = 43)	ET (n = 43)	p
Post-operative discomfort (%)			1.000
Yes	2 (4.7)	1 (2.3)
No	41 (95.3)	42 (97.7)
Symptom relief (%)			0.632
Fully	40 (93.0)	41 (95.3)
Partially	2 (4.7)	2 (4.7)
No	1 (2.3)	0 (0)
Cosmetic relief (%)			0.317
Fully	42 (97.7)	43 (100)
Partially	1 (2.3)	0 (0)
No	0 (0)	0 (0)
Post-operative levothyroxine use (%)			<0.01
Yes	0 (0)	8 (18.6)
No	43 (100)	35 (81.4)
Overall satisfaction (%)			0.303
Fully	40 (93.0)	42 (97.7)
Partially	2 (4.7)	1 (2.3)
No	1 (2.3)	0 (0)

TA: thermal ablation; ET: endoscopic thyroidectomy; BTNs: benign thyroid nodules.

Data are presented as numbers (percentages).