Objective To investigate the effect of iodine-125 on inhibiting breast cancer growth and to explore its possible mechanism. Methods The animal model of the MCF-7 tumor was established firstly through injection of the cells into nude mice. The animals were divided into two groups before the implantation of the iodine-125 granule into the tumor mass: control group (n=40, to implant no-load seeds, non-iodine-125 radioelement) and experimental group 〔n=40, to implant iodine-125 seeds (1.48×107 Bq) when the length of tumor was 8-10 mm〕. The width and length of tumor, in order to calculate the volume, were measured every three days to observe tumor growth curve and to calculate the rate of the tumor inhibition. When the length of tumor was 15-20 mm in the control group, 30 nude mice were killed in every group to detect the weight of tumor and histopathological changes. Other ten nude mice of each group were remained to be observed the national life span and survival rate for 90 days. Results Within 90 days, the average survival time in control group and experimental group were significantly different (56.2 d vs. 74.8 d, P＜0.05). In control group the growth curve was continuously elevated, while experimental group showed a low flat curve. With iodine-125 treatment, the tumor growth decreased in experimental group with tumor inhibition rate 55.21%. The average tumor weight in control group and experimental group was (3.26±0.39) g and (1.46±0.17) g (t′=22.8962, P＜0.05). As compared with control group, under light microscope, the number of cancer cells was less, nuclear debris increased, and cancer structure was not obvious in experimental group. Conclusion This study suggests that iodine-125 seed may inhibit the growth of breast cancer, which may be involved in direct radiation breakdown of tumor cells or induction of apoptosis and inhabitation of tumor angiogenesis.
The iodine-125 (125I) seeds interstitial implantation has the advantages of minimal invasiveness, high local control rate, and few complications; it has attracted worldwide attention. With the application of 3D printing technology in medicine, individualized 3D templates are gradually applied to clinical practice. Individualized 3D templates combining with CT-guided 125I seeds implantation are easy to operate and can not only effectively ensure the consistency and accuracy of preoperative and postoperative dose, but also minimize complications to achieve optimal efficacy. This paper reviews the application of CT-guided implantation of 125I seeds for malignant tumors assisted by individualized 3D template, and further demonstrates the safety and effectiveness of clinical application in 125I seeds implantation to provide a reliable basis for the standardization of 125I seeds implantation.