Table 1.

Characteristics of the included studies

Study, year [ref.]	Design	Publication	T/C	Age (y)	Male/female	Tumor stage	Tumor size	Tumor location	T (dose)/C	Follow-up (months)
Jiakai Li, 2013 [11]	Retrospective study	Mol Clinl Oncol	24 (28 lesions)/0	Mean, 65.4 (54-81)	18/6	T1-3N0M0	4.0 ±1.5	N.A.	125I (100-120 Gy)/ –	Median, 31.5 (8-46)
Bin Huo, 2017 [12]	Retrospective study	Chin J Radiol Med Prot	21/0	Median, 69 (58-80)	15/6	T1-2N0M0	≥ 3 cm: n = 6 < 3 cm: n = 15	P: 19, Central: 2	125I (120-160 Gy)/ –	Median, 25.1 (4.4-72.7)
Jingkui Yang, 2014 [13]	Retrospective study	Chin J Clin Oncol	48/0	67.9 ±8.6	35/13	I-II (N0)	Median, 2.1 cm (0.7-3.0)	P	125I (110 Gy)/–	N.A.
Mingyao Ke, 2011 [14]	Retrospective study	Chin J Radiat Oncol	16/0	Median, 74 (70-82)	11/5	I	> 3 cm: n = 3 ≤ 3 cm: n = 13	P	125I (140-160 Gy)/ –	Mean, 35 (10-56)
Jingkui Yang, 2014 [20]	Retrospective study	Chin J Geriatrics	18/0	Median, 73.7 (60-89)	12/6	I-II (N0)	Median, 2.1 cm (0.7-3.0)	N.A.	125I (110 Gy)/–	N.A.
Hua Cheng, 2019 [21]	Retrospective study	World Latest Medicine Information	26/0	Median, 68.5 (50-89)	15/11	T1-3N0M0	Median, 2.6 cm (1.2-5.0)	N.A.	125I (100-120 Gy)/ –	Mean, 41 (10-50)
Wei Fu, 2019 [22]	RCTs	J Pract Radiol	25/24	T: 63.24 ±1.27 C: 63.18 ±1.24	31/18	I-II (N0)	T: ≥ 3 cm: n = 8 < 3 cm: n = 17 C: ≥ 3 cm: n = 6 < 3 cm: n = 18	TP: 22, Central: 3, CP: 22, Central: 2	125I (N.A.)/TP	T: Mean, 14 (6-24) C: Mean, 13 (7-24)
Jianguo Yang, 2018 [23]	RCTs	Chinese Journal of Practical Medicine	34/33	T: 55.80 ±9.30 C: 56.40 ±9.52	40/27	I-II	N.A.	N.A.	125I + GC (NA)/GC	42 days
Xianghua Lin, 2016 [24]	RCTs	J Medical Forum	20/19	42-79	21/18	I-II	0.8-3.0	P: 26, Central: 13	125I + GC (80-110 Gy)/GC	6 months

T – treatment group, C – control group, TP – taxol + cisplatin, GC – gemcitabine + cisplatin, ¹²⁵I – iodine-125, CT – computed tomography, P – peripheral, N.A. – not available