ObjectiveTo evaluate the viability, short-term clinical efficacy, and safety of ultrasound-guided radioactive seed 125I permanent implantation in tissue in patients with advanced colorectal cancer. MethodsA total of 9 patients were recruited in this study. All of the patients came from China-Japan Union Hospital of Jilin University from October 2012 to October 2014, which had been selected after strict screening. Five cases of male patients, 4 cases of female patients; the age was between 46-78 years old, the median age was 54 years old. There were 5 cases of patients with pain. There were 14 lesions in total, 1 lesion was local tumor recurrence, 2 lesions were pelvic metastasis, 8 lesions were liver metastases, and 3 lesions were abdominal lymph node metastasis. CEA increased in 6 cases before implantation. All patients were confirmed metastasis by CT, MRI examination or pathology. The 125I radioactive seed implantation was guided by real-time ultrasound. CT scanning was taken in two months after treatment. The degree of pain relief, tumor local control, and the occurrence of complications were observed. ResultsIn 2 months after implantation of 125I radioactive particles, the CT scanning results showed that 2 cases obtained complete response (CR), 5 cases obtained partial response (PR), 1 case got stable disease (SD), and 1 case got progress disease (PD). Total effective was 7/9, and disease control was 8/9. Five cases with pain symptoms were relieved after treatment. One walk metal particle in the abdominal cavity was found by abdominal CT scanning in 1 case. There were no serious complications intraoperative and postoperative. ConclusionsUltrasound guided radioactive seeds 125I implantation in the treatment of advanced colorectal cancer can significantly relieve the clinical symptoms, improve the quality of life, and can effectively control the metastasis. It is safe and feasible, and the postoperative hospitalization time is short, it has the avantages of safety, effectiveness, and low incidence of complications.