Efficacy and safety of radiofrequency ablation for primary and secondary hyperparathyroidism with or without previous parathyroidectomy: a retrospective study

Figures & data

Table 1. Patient characteristics and treatment details.

	HPT (total)	PHPT		SHPT
			Total	Without PTX	With PTX	p	p^+	p^$
Number	21	7	14	9	5
Age (year)	54.80 ± 13.40	57.9 ± 12.6	53.21 ± 14.01	51.80 ± 16.00	55.80 ± 10.60	0.681	0.739	0.887
Hemodialysis duration (year)			10.83 ± 6.07	9.10 ± 6.80	13.20 ± 4.50		0.287
Sex (male/Female)	10/11	2/5	8/6	6/3	2/3			0.295
Baseline Clinical scores	2.30 ± 1.60	1.40 ± 1.00	2.79 ± 1.63	3.20 ± 1.70	2.00 ± 1.20	0.062	0.248	0.168
Nodular characteristics
Number of Nodules	2.00 ± 1.30	1.00 ± 0.00	2.50 ± 1.34	3.20 ± 1.10	1.20 ± 0.40^+	0.009*	0.008*	0.001*
Longest diameter (cm)	1.80 ± 0.80	1.90 ± 0.80	1.75 ± 0.75	1.70 ± 0.70	1.90 ± 1.00	0.681	0.549	0.815
Baseline Volume (ml)	1.60 ± 1.60	1.40 ± 1.20	1.70 ± 1.85	1.70 ± 1.90	1.70 ± 2.00	0.970	0.739	0.956
Technical characteristics
Total ablation time (minute)	9.60 ± 7.40	6.50 ± 5.10	11.17 ± 7.97	14.30 ± 8.30	5.60 ± 2.90	0.062	0.003*	0.004*
Time/Volume (minute/ml)	5.40 ± 3.50	6.50 ± 5.10	47.84 ± 23.53	4.80 ± 2.50	4.70 ± 2.30	0.654	0.947	0.905
Total Energy (Kcal)	2.15 ± 2.41	1.46 ± 1.14	2.56 ± 2.88	2.98 ± 3.25	1.28 ± 0.40	0.272	0.116	0.225
Energy/Volume (Kcal/ml)	1.17 ± 0.92	1.46 ± 1.14	0.99 ± 0.76	0.97 ± 0.84	1.08 ± 0.56	0.526	0.229	0.529

Values are shown as mean ± standard deviation unless otherwise indicated.

P: calculated using data of PHPT and total SHPT.

P⁺: calculated using data of SHPT without PTX and SHPT with PTX.

P^$: calculated using data of PHPT, SHPT without PTX, and SHPT with PTX.

*: p < 0.05.

⁺: The number of PTX-removed parathyroid nodules were 3, 4, 4, 4, and 5 (all 4 parathyroid glands and 1 ectopic parathyroid nodule,) respectively.

HPT: hyperparathyroidism; PHPT: primary hyperparathyroidism; SHPT: secondary hyperparathyroidism; PTX: parathyroidectomy.

Table 2. Outcomes based on nodule volume change and clinical results.

	HPT (Total)	PHPT	p^1	p^2	SHPT
					Total	p^3	p^4	Without PTX	p^5	p^6	With PTX	p^7	p^8	p	p^+	p^$
Nodule volume (Mean ± SD, ml)
Baseline	1.36 ± 1.62	1.40 ± 1.25			1.35 ± 1.7			1.32 ± 1.69			1.47 ± 1.90			0.469	0.507	0.607
1 month	1.03 ± 1.36	0.84 ± 0.73	0.018*	0.018*	1.07 ± 1.48	<0.001	<0.001	1.15 ± 1.60	<0.001	<0.001	0.80 ± 1.02	0.080	0.080	0.786	0.713	0.892
3 months	0.54 ± 0.62	0.43 ± 0.27	0.018*	0.028*	0.59 ± 0.72	<0.001	0.005*	0.64 ± 0.79	0.001*	0.018*	0.34 ± 0.30	0.109	0.109	0.442	0.918	0.719
6 months	0.20 ± 0.18	0.15 ± 0.03	0.068	0.066	0.23 ± 0.21	0.012*	0.068	0.22 ± 0.25	0.028*	0.109	0.27 ± 0.10	0.180	0.317	0.562	0.857	0.522
12 months	0.08 ± 0.08	0.06 ± 0.02	0.180	0.180	0.09 ± 0.09	0.012*	0.043*	0.05 ± 0.06	0.028*	0.109	0.20 ± 0.08	0.180	0.180	1.000	0.071	0.127
Volume reduction ratio (Mean ± SD, %)
1 month	40.10 ± 30.62	30.82 ± 20.60			42.09 ± 32.31			44.99 ± 29.41			31.45 ± 42.81			0.466	0.494	0.573
3 months	67.96 ± 17.61	60.31 ± 12.70	0.028*	0.028*	71.31 ± 18.74	0.005*	0.005*	73.46 ± 19.86	0.018*	0.018*	61.97 ± 10.29	0.109	0.109	0.222	0.362	0.296
6 months	83.86 ± 16.28	78.06 ± 20.03	0.068	0.068	87.08 ± 14.06	0.028*	0.068	92.47 ± 9.40	0.068	0.109	68.2 ± 11.6	0.180	0.317	0.435	0.139	0.091
12 months	93.76 ± 9.45	95.05 ± 3.89	0.180	0.180	93.44 ± 10.59	0.043*	0.043*	98.93 ± 1.51	0.109	0.109	76.95 ± 7.00	0.180	0.180	0.556	0.036*	0.049*
Complications
Hoarseness	3	1			2			2			0			1.000	0.237	0.539
Neck pain	5	0			5			4			1			0.077	0.378	0.127
Complication scores	0.43 ± 0.60	0.14 ± 0.38			0.57 ± 0.65			0.78 ± 0.67			0.20 ± 0.45			0.115	0.101	0.065
Symptomatic score
Baseline	2.33 ± 1.56	1.43 ± 0.98			2.79 ± 1.63			3.22 ± 1.72			2.00 ± 1.22			0.062	0.248	0.102
1 month	0.33 ± 0.73	0.14 ± 0.38	0.024*	0.024*	0.43 ± 0.85	0.001*	0.001*	0.56 ± 1.01	0.007*	0.007*	0.20 ± 0.45	0.066	0.066	0.451	0.556	0.619
3 months	0.20 ± 0.41	0 ± 0	0.026*	0.317	0.31 ± 0.48	0.003*	0.317	0.38 ± 0.52	0.017*	0.317	0.20 ± 0.45	0.066	1	0.110	0.523	0.210
6 months	0.05 ± 0.22	0 ± 0	0.026*	1	0.08 ± 0.28	0.002*	0.083	0.13 ± 0.35	0.011*	0.157	0 ± 0	0.063	0.317	0.463	0.429	0.472

Values are shown as mean ± standard deviation unless otherwise indicated.

P¹: calculated using data of baseline and each follow-up time in PHPT group.

P²: calculated using data of each follow-up time and the previous follow-up time in PHPT group.

P³: calculated using data of baseline and each follow-up time in total SHPT group.

P⁴: calculated using data of each follow-up time and the previous follow-up time in total SHPT group.

P⁵: calculated using data of baseline and each follow-up time in SHPT without PTX group.

P⁶: calculated using data of each follow-up time and the previous follow-up time in SHPT without PTX group.

P⁷: calculated using data of baseline and each follow-up time in SHPT with PTX group.

P⁸: calculated using data of each follow-up time and the previous follow-up time in SHPT with PTX group.

P: calculated using data of PHPT and total SHPT.

P⁺: calculated using data of SHPT without PTX and SHPT with PTX.

P^$: calculated using data of PHPT, SHPT without PTX, and SHPT with PTX.

*: p < 0.05.

HPT: hyperparathyroidism; PHPT: primary hyperparathyroidism; SHPT: secondary hyperparathyroidism; PTX: parathyroidectomy.

Figure 1. Changes in iPTH, serum calcium levels, nodule volume, and volume reduction ratio (VRR) of the three groups before and after hyperplastic parathyroid gland radiofrequency ablation (RFA) at each follow-up. The iPTH in PHPT and SHPT both showed successful treatment responses compared with baseline (A) even though both SHPT subgroups showed a transient rebound (B). The calcium level in PHPT and SHPT both decreased at follow-up duration (C), but SHPT groups experienced transient hypocalcemia, especially in the SHPT without PTX subgroup (D). Nodule volumes in all three groups significantly decreased over time after RFA (E). The VRR in PHPT and SHPT without PTX were both over 95% and significantly higher than SHPT with PTX (F). *p < 0.05 versus baseline.

Table 3. Laboratory outcomes.

	PHPT	p^1	p^2	SHPT									p	p^+
				Total	p^3	p^4	Without PTX	p^5	p^6	With PTX	p^7	p^8
iPTH level (pg/mL)
Baseline	233.96 ± 108.92			2050.04 ± 1189.05			1971.4 ± 812.24			2191.58 ± 1799.05			<0.001	0.841
1 day	55.02 ± 53.37	0.028*	0.028*	526.10 ± 580.45	0.002*	0.002*	352.14 ± 170.31	0.008*	0.008	1047.97 ± 1091.94	0.109	0.109	0.001*	0.405
1 week	55.27 ± 11.54	0.109	1.000	845.80 ± 1314.60	0.002*	0.041*	513.41 ± 325.88	0.008*	0.066	1593.68 ± 2356.32	0.273	0.655	0.069	0.537
1 month	72.52 ± 54.11	0.043*	0.655	1059.08 ± 1345.31	0.004*	0.060	641.31 ± 331.44	0.012*	0.123	1727.52 ± 2080.81	0.345	0.144	0.005*	0.380
3 months	57.57 ± 16.16	0.018*	0.345	562.65 ± 429.05	0.003*	0.308	605.30 ± 417.90	0.018*	0.310	502.94 ± 486.45	0.080	0.686	0.003*	0.372
6 months	45.15 ± 10.65	0.028*	0.028*	361.63 ± 313.30	0.002*	0.019*	342.16 ± 187.99	0.018*	0.091	388.90 ± 464.04	0.043*	0.043*	0.001*	0.808
12 months	55.35 ± 19.11	0.028*	0.075	429.48 ± 499.70	0.002*	0.638	258.76 ± 169.34	0.018*	0.091	668.50 ± 721.97	0.043*	0.500	0.005*	0.372
Calcium level (mg/dL)
Baseline	11.30 ± 0.94			10.36 ± 0.60			10.40 ± 0.48			10.30 ± 0.84			0.020*	0.893
1 day	11.20 ± 0.82	0.735	0.735	10.15 ± 0.85	0.183	0.183	10.43 ± 0.77	0.906	0.906	9.50 ± 0.73	0.068	0.068	0.021*	0.103
1 week	9.43 ± 0.43	0.068	0.068	7.71 ± 1.41	0.001*	0.001*	7.27 ± 1.37	0.008*	0.008*	8.70 ± 1.01	0.068	0.066	0.017*	0.122
1 month	9.36 ± 0.59	0.043*	0.102	8.40 ± 1.09	0.001*	0.011*	7.90 ± 0.91	0.012*	0.068	9.20 ± 0.90	0.043*	0.066	0.084	0.067
3 months	9.71 ± 0.71	0.018*	0.223	8.90 ± 1.06	0.007*	0.117	8.83 ± 1.21	0.043*	0.063	9.00 ± 0.94	0.043*	0.686	0.091	0.935
6 months	9.73 ± 0.54	0.028*	0.916	9.17 ± 0.67	0.006*	0.126	8.99 ± 0.60	0.018*	0.500	9.42 ± 0.73	0.138	0.080	0.067	0.568
12 months	9.82 ± 0.77	0.028*	0.655	9.73 ± 0.42	0.011*	0.012*	9.71 ± 0.32	0.017*	0.018*	9.76 ± 0.57	0.176	0.416	0.814	0.934

Values are shown as mean ± standard deviation unless otherwise indicated. Numbers in parenthesis are ranges.

P¹: calculated using data of baseline and each follow-up time in PHPT group.

P²: calculated using data of each follow-up time and the previous follow-up time in PHPT group.

P³: calculated using data of baseline and each follow-up time in total SHPT group.

P⁴: calculated using data of each follow-up time and the previous follow-up time in total SHPT group.

P⁵: calculated using data of baseline and each follow-up time in SHPT without PTX group.

P⁶: calculated using data of each follow-up time and the previous follow-up time in SHPT without PTX group.

P⁷: calculated using data of baseline and each follow-up time in SHPT with PTX group.

P⁸: calculated using data of each follow-up time and the previous follow-up time in SHPT with PTX group.

P: calculated using data of PHPT and total SHPT.

P⁺: calculated using data of SHPT without PTX and SHPT with PTX.

*: p < 0.05.

HPT: hyperparathyroidism; PHPT: primary hyperparathyroidism; SHPT: secondary hyperparathyroidism; PTX: parathyroidectomy.

Figure 2. A 54-year-old female with primary hyperparathyroidism. Technetium (99mTC)-sestamibi scan (A) and US examination (B) revealed a hyperfunctional left lower parathyroid adenoma measuring 14.5 mm × 6.3 mm. CT scan of the parathyroid adenoma (arrow) without (C) and with contrast enhancement before RFA (D). CT scan without (E) and with contrast enhancement 1 year after RFA (F) showed total regression (arrow) of the left inferior parathyroid adenoma. Serum PTH and calcium levels were decreased and remained in the normal range at the 1-year follow-up. RFA: radiofrequency ablation; PTH: parathyroid hormone; US: ultrasound.

Figure 3. A 41-year-old female with secondary hyperparathyroidism status post parathyroidectomy. Technetium (99mTC)-sestamibi scan (A) revealed a left inferior hyperparathyroid nodule, with high signal also shown on forearm due to parathyroid tissue autotransplantation postparathyroidectomy. Contrast-enhanced CT scan of coronal (B) and axial view (C) revealed a hyperplastic parathyroid nodule in the left inferior neck (arrow). US examination (D) revealed a left inferior parathyroid hyperplastic nodule measuring 8.6 mm × 7.3 mm. US examination follow-up at 4 months after RFA (E) showed significant decrease in size of the nodule measuring 6.1 mm × 5.2 mm. Serum PTH and calcium levels were decreased at 3-month follow-up after treatment. RFA: radiofrequency ablation; PTH: parathyroid hormone; US: ultrasound.