Treatment of recurrent cervical cancer is still a challenge at present, especially for those with a history of radiotherapy. After standard radical surgery or chemoradiotherapy, 20%~40% of cervical cancer patients still have local recurrence or distant metastasis[7–8]. The choice of treatment for recurrent cervical cancer should be comprehensively evaluated according to the initial treatment, the general situation of patients and the recurrence site. Treatment regimens include targeted radiotherapy, brachytherapy and/or chemotherapy and surgery. Local palliative radiotherapy is mainly used in patients with cervical cancer with few metastases or bone metastases. Most patients with local palliative radiotherapy cannot be given a sufficient radiation dose because the radiation tolerance dose of normal tissue has not been restored. The curative effect of traditional radiotherapy and chemotherapy is poor, and complications are obvious. The tolerance and quality of life of patients are poor [9–11]. Immunotherapy is the main treatment for recurrent cervical cancer, but its clinical application is greatly limited due to its high price. Afterloading therapy is one of the most important radiotherapy methods for patients with locally advanced cervical cancer. However, for patients with distant metastasis, due to the limitation of lumen coverage and the dose limitation of risk organs, the target dose is insufficient, rendering the patient prone to tumor recurrence and out of control growth. Because the patient could not undergo surgery and the lesion site involved distant metastasis, 125I seed implantation plus chemotherapy was selected.
125I seed implantation is a reasonable distribution,minimally invasive and repeatable procedure that has unique advantages in the treatment of locally advanced tumors [12–13]. Clinical studies have shown that 125I seed implantation in the treatment of pelvic malignant tumors, including recurrent or metastatic colorectal cancer, ovarian cancer, and cervical cancer, can elevate the local control rate, alleviate clinical symptoms, and improve the survival time of patients[14–17]. Qu et al.  reported the treatment of recurrent cervical cancer with 125I seed implantation in 36 patients. The median survival times for the central-type and peripheral-type patients were 6 months and 12 months, respectively, and the one-year progression-free survival (PFS) rates were 26.7% and 41.6%, suggesting that 125I seed implantation had a better effect in peripheral cervical cancer than in central cervical cancer. According to Han et al. , 17 patients with recurrent cervical cancer were treated with 125I seed implantation under CT guidance, and the MPD was 145 Gy. The results showed that the total effective rate was 58.0%, and the 1-year survival rate was approximately 18.3%. Two patients had symptoms of sciatic nerve injury but no other serious complications. Silva et al  reported that 45 patients were treated with 125I seed implantation after relapse, and 30 patients (67%) had complete clinical remission. The 5-year survival rate after relapse was 52%. 125I seed implantation in the treatment of recurrent cervical cancer has the advantages of an exact curative effect, fewer complications and good tolerance of patients. It may become an effective treatment method for recurrent cervical cancer that is not responsive to multicourse treatment.
The most common sites of extrapelvic metastasis are the para-aortic lymph nodes (81%), lung (21%) and supraclavicular lymph nodes (7%). In this patient, the metastatic sites were the retroperitoneal lymph nodes and supraclavicular lymph nodes. It is impossible for interstitial brachytherapy or afterload to treat this kind of lymph node metastasis. With CT guidance, 125I seed implantation was successfully implanted into the lymph nodes. One month after 125I seed implantation, a pelvic CT scan showed that the lymph nodes were smaller than before. After 3 months, the patients were hospitalized again. Pelvic CT and chest CT showed that the particles accumulated at the site of retroperitoneal lymph node metastasis, and the size of lymph nodes was significantly smaller than before. The enlargement of the supraclavicular lymph nodes disappeared. Thirteen months after implantation, the patient was readmitted to the hospital for CT review. According to the RECIST standard, the therapeutic effect reached CR. In the second half of the year, no progress was observed. The latest evaluation of the patient showed that the PFS time had reached 6 years and 4 months. The PFS of this patient was significantly higher than that observed in other studies. The following three reasons were considered possible explanations: First, the clinical stage of this patient was early IB, and the prognosis was good. Second, although some studies have shown that the site of cervical cancer recurrence is one of the factors influencing the survival time of patients, the metastatic site of the patient indicates poor prognosis, and the metastatic focus in this case was given a radical dose, which may prolong the survival time of patients. Last, the patient was given 6 cycles of TP Regimen adjuvant chemotherapy after particle implantation, suggesting that particle combined chemotherapy can effectively improve the survival time of the patient. The depressed edema of the left lower limb disappeared after the operation, and the pressure of the lymph node metastasis on the blood vessels was relieved, effectively alleviating the symptoms of poor movement, suggesting that particle implantation can effectively improve the quality of life and survival time of patients.
This case showed that 125I seed implantation is an effective treatment for recurrent lymph node metastasis of cervical cancer that can effectively alleviate the symptoms of edema and left lower limb movement limitation and achieve a good therapeutic effect. As it is a local treatment, 125I seed implantation can be used as a supplementary treatment for recurrent cervical cancer. It is a reliable means for comprehensive treatment of primary cervical cancer. At present, there are still deficiencies. A large sample size and more clinical trials and studies are needed to obtain more reliable evidence-based recommendations.