125I Seeds Research Articles

Preoperative radio-guided localization of lung nodules with I-125 seeds: experience with 32 patients at a single institution.

Videothoracoscopic visualization and/or palpation of pulmonary nodules may be difficult due to their location, small size or limited solid component. The purpose of this study is to present our experience with computed tomography (CT)-guided preoperative localization of pulmonary nodules by percutaneous marking with radio-labelled iodine-125 seeds. A total of 34 pulmonary nodules were marked under CT with the placement of 33 radio-labelled iodine-125 seeds in 32 consecutive patients. All patients underwent biportal video-assisted thoracic surgery (VATS) and in no case was conversion to thoracotomy necessary. A total of 88.2% of the lung nodules were successfully resected. In the remaining 11.8%, migration of the seed to the pleural cavity occurred, although these nodules were still resected during VATS. Of all the patients with pneumothorax after the marking procedure, only one required chest tube placement (3.1%). No major postoperative complications were observed. Preoperative marking of pulmonary nodules with I-125 seeds under CT guidance is a feasible and safe technique that allows their intraoperative identification and resection.

Relationship between miR-7-5p expression and 125I seed implantation efficacy in pancreatic cancer and functional analysis of target genes*

Abstract Objective The aim of this study was to investigate the relationship between miR-7-5p expression and intertissue-125I irradiation sensitivity in pancreatic cancer tissues and to analyze the function of target genes. Methods Thirty-seven patients with unresectable pancreatic ductal adenocarcinoma (PDAC) treated with radioactive 125I seed implantation were enrolled. RT-PCR was used to detect the expression level of miR-7-5p in cancer tissues and analyze the relationship between miR-7-5p expression and 125I radiation sensitivity. Bioinformatic software and online tools were used to predict the miR-7-5p target genes and analyze their functional annotation and pathway enrichment. Results Radioactive 125I seed implantation was followed up for 2 months. The objective response rate of the miR-7-5p high expression group was 65.0% (13/20), whereas the objective response rate of the miR-7-5p low expression group was 5.88% (1/17), and the difference between the two groups was statistically significant (χ 2 = 13.654, P < 0.001). A total of 187 target genes were predicted using three databases. GO functional annotation showed that target genes were mainly involved in cellular response to insulin stimulus, regulation of gene expression by genetic imprinting, cytosol, peptidyl-serine phosphorylation, bHLH transcription factor binding, cargo loading into vesicles, cellular response to epinephrine stimulus, and nucleoplasm. KEGG pathway enrichment analysis showed that target genes were mainly involved in the ErbB signaling pathway, HIF-1 signaling pathway, axon guidance, longevity regulatory pathway, endocrine resistance, glioma, choline metabolism in cancer, and EGFR tyrosine kinase inhibitor drug resistance. Molecular complex detection analysis by Cytoscape revealed that PIGH, RAF1, EGFR, NXT2, PIK3CD, PIK3R3, ERBB4, TRMT13, and C5orf22 were the key modules of miR-7-5p target gene clustering. Conclusion The expression of miR-7-5p in pancreatic cancer tissues positively correlated with the radiosensitivity of 125I seeds. Via targeted gene regulation, miR-7-5p acts on the network of multiple signaling pathways in PDAC and participates in its occurrence and development. Thus, miR-7-5p may become a predictive index of 125I seed implantation therapy sensitivity in PDAC patients.

Development of a Novel Endovascular Brachytherapy Stent: A Proof-of-concept Study.

Background and AimsEndovascular implantation of iodine-125 (125I) seeds strand combined with stent is an effective method of treatment for portal vein tumor thrombosis. The aim of this study was to develop a novel endovascular brachytherapy stent (EVB-Stent) and to evaluate its feasibility of use.MethodsAn EVB-Stent was implanted into the main portal vein (MPV) in a live porcine model via the percutaneous transhepatic route. Blood samples were collected and tested before and after operation, as well as before euthanasia. Single-photon emission computed tomography (SPECT) combined with CT (SPECT/CT) scan were performed directly after operation and CT scan was performed 2 months after implantation. After the CT scan was performed, all animals were euthanized and histologically examined.ResultsThe novel stent was successfully positioned in all six pigs. No deterioration of liver function was observed during the 2-month follow-up period. SPECT/CT revealed the uniform distribution of radiation around the seeds strand, and the hottest spot was near the center of the MPV. The patency of the stented MPV was confirmed using CT scans. The tissue-accumulated absorbed dose was 31,822.11 mGy at 10 mm transversely away from the midpoint of the 125I seeds strand, with a half-life of 59.4 days. Pathological examination results showed no significant atrophy or inflammation of adjunct liver tissue, and no obvious intima thickening or thrombosis were detected in the stented MPV.ConclusionsA liver porcine model was used to demonstrate that the transhepatic placement of a novel endovascular brachytherapy stent, EVB-Stent, is both technically feasible and safe.

A Comparative Study of Self-Expandable Metallic Stent Combined with Double 125I Seeds Strands or Single 125I Seeds Strand in the Treatment of Advanced Perihilar Cholangiocarcinoma with Malignant Obstructive Jaundice.

PurposeThe purpose of this study was to compare the safety and effectiveness of a self-expandable metallic stent (SEMs) with a novel brachytherapy biliary drainage catheter (BBDC, double 125I seeds strands) or a single 125I seeds strand in the treatment of advanced perihilar cholangiocarcinoma (pCCA) with malignant obstructive jaundice (MOJ).MethodsFrom September 2016 to December 2018, we retrospectively enrolled patients with biliary stent implantation after receiving either BBDC loaded with 125I seeds (double-strands irradiation group) or an 125I seed strand treatment (single-strand irradiation group, control group). The outcomes were analyzed regarding the relief of obstructive jaundice, and interventional-related complications. Moreover, the Kaplan–Meier method was used to analyze stent patency and survival.ResultsThe success rate of interventional therapy in both groups was 100%, and all patients with MOJ were alleviated. According to the Common Terminology Criteria for Adverse Events (CTCAE 4.02), the grade 3 or 4 complications in the BBDC group and in the control group were 6/34 (17.65%) and 7/39 (17.95%), respectively (P > 0.05). The median and mean overall stent patency of the BBDC group and the control group were 207 days versus 180 days, 204.212 days versus 186.278 days (P = 0.043). The median and mean overall survivals in the BBDC group were higher than those in the control group (245 days versus 212 days, 244.883 days versus 221.844 days, P = 0.030).ConclusionThis interim analysis showed that BBDC (double-stranded irradiation) can prolong the stent patency time compared with 125I seed strand treatment (single-stranded irradiation) and had the advantage of reducing jaundice, which seemed to extend the survival period of advanced pCCA.

Optic Disc Dose Comparison Between 125I and 103Pd Collaborative Ocular Melanoma Study (COMS) Plaques Based on Current Clinical Practice.

PurposeThe purpose of this study is to compare optic disc dose (ODD) between 125I and 103Pd Collaborative Ocular Melanoma Study (COMS) plaques in ocular brachytherapy.MethodsA previously validated in-house brachytherapy dose calculation program was used for ODD calculations. ODD was calculated as a function of tumor margin-to-optic disc distance (DT) up to 5 mm for various tumor basal dimensions (BDs), for a prescription depth of 5 mm, and for standard and notched COMS plaques loaded with 125I (model: IAI-125A) and 103Pd (model: IAPd-103A) seeds. ODD calculations were repeated for prescription depths from 2 mm to 10 mm in 1 mm intervals. A prescribed dose of 85 Gy (irradiation time: 120 hours) was normalized to each prescription depth. Dose conversion factors (DCFs) for each prescription depth were calculated by taking a ratio of [total reference air kerma (TRAK) per seed]prescription depth to [TRAK per seed]5 mm. ODD reduction by notched COMS plaques was calculated for each prescription depth by subtracting ODD for notched COMS plaques from ODD for standard COMS plaques.ResultsTrends of ODD as a function of DT for various BDs are similar between the two seed types in both standard and notched COMS plaques. However, due to the energy difference, there exists a transition distance (dt) for each BD in each plaque at which ODD for 125I COMS plaques equals that for 103Pd COMS plaques. For small BDs, at DT <dt, ODD for 103Pd COMS plaques is higher than that for 125I COMS plaques while at DT >dt, the opposite is observed. For the largest 1-3 BD(s), contrarily, dt occurs within the tumor, and thus, ODD for 125I COMS plaquesis always higher. Trends of ODD reduction by notched COMS plaques as a function of DT for various BDs are the same for the two seed types except that maximum ODD reduction by 103Pd COMS notched plaques is larger. DCF increases with increasing prescription depth for both seed types.ConclusionsThere exist ODD differences between 125I and 103Pd COMS plaques and the differences depend on DT, BD, plaque size, and prescription depth.

Design and fabrication of 125I seeds for brachytherapy using capillary-based microfluidic technique

Abstract A new kind of 125I seeds with a core-shell structure were synthesized by an easy assembling–disassembling coaxial capillaries microfluidic device. The dose distribution of a 125I brachytherapy source fabricated by arranging six 125I seeds collinearly within a cylindrical titanium capsule was simulated by modelling the source in a water phantom using Monte Carlo N-Particle Transport code. The influence of the motion and the core size of the 125I seeds on the dose distribution was also studied in this work.

125I Intracavitary Irradiation Combined with 125I Seeds Implantation for Treatment of Locally Advanced Pancreatic Head Cancer: A Retrospective Analysis of 67 Cases.

BackgroundPancreatic cancer is an aggressive malignant tumor of the digestive system and the fourth leading cause of tumor-related death. Intracavitary 125I seed irradiation has been recently developed as a therapy for locally advanced pancreatic head carcinoma. However, there are still many limitations, and more investigations are needed in order to optimize this new treatment method.MethodsSixty-seven patients were included in our study; 41 cases treated by SEMS-CL-125I intracavular irradiation (SEMS-CL-125I group) and 26 cases treated by SEMS-CL-125I intracavular irradiation combined with 125I particle implantation in the tumor body (the combined group). Among the 67 patients, 43 were males and 24 were females, with an average age of 69.64±8.84 years. Tumor site size was determined based on the MRI or CT imaging scans, and the number and radius of 125I particle placement were calculated according to a specific formula. 125I particles were inserted into the tumor with a radius of 1.5 cm and a row spacing of 1 cm. The main postoperative biochemical indexes, imaging analysis, postoperative analgesia degree, median survival time and rate of complications were compared between the two groups.ResultsJaundice and liver function improved in both groups after treatment for 6 months. The combined group did better. Kaplan–Meier analysis showed that patients in the combined group had a significantly better overall survival than those in the SEMS-CL-125I group. Patients in the combined group had less complications than those in the SEMS-CL-125I group (23.1% vs 34.1%), and the postoperative pain status of the combined group was improved (26.8% vs 53.8%).ConclusionCompared with the SEMS-CL-125I intracavular irradiation alone, the combination of 125I seed implantation with solid tumor 125I seed implantation had a better therapeutic effect in LAPHC patients, with improved biochemical indicators, survival prognosis, pain relief, and fewer complications.

125I seed combined with DCS loaded with tumor antigen to convert irradiated liver cancer into effective in situ vaccine.

e14573 Background: With unique feature of self-immune tolerance and high radio-sensitivity, hepatocellular carcinoma (HCC) can gradually develop undesired effects. Iodine-125 (125I) seed, as a source of internal radiation therapy, may have a favorable adaptability and immunostimulation. In this study, we investigated whether 125I seeds can stimulate local tumor infiltrating lymphocytes (TILs) and whether a combination of 125I seeds and dendritic cells (DCs) loaded with tumor antigen (Ag+DCs) can enhance both local tumor control and abscopal effect in murine subcutaneous tumor models. The related mechanism of anti-tumor immune response was also explored. Methods: H22/Hepa1-6 HCC cells were examined for radiosensitivity and immunosensitivity. Cell apoptosis and expression of MHC-I (major histocompatibility complex class I) and PD-L1 (programmed death-ligand 1) were detected before and after irradiation. The tumor cells were injected subcutaneously as primary and abscopal tumor. Bone marrow-derived dendritic cells (BM-DCs) were induced from mouse bone marrow cells and incubated with tumor cell lysate. 125I seeds were implanted into the primary tumors, followed by intratumoral injection of Ag+DCs and intraperitoneal injection of αPD1 antibody (αPD1-ab). DC migration was detected by transwell chambers in vitro and CFSE (carboxyfluorescein succinimidyl ester)-labeled DCs in vivo. DC maturation was tested by flow cytometry. Analyses of tumor growth and survival rates were performed in vitro, and that of, TILs, T-cell proliferation, cytotoxicity test, immunostimulatory cytokines release, and immunological memory were performed in vivo. In situ vaccine and abscopal effect were verified in orthotopic mouse models of liver cancer and lung metastatic tumor. Results: 125I seeds alone could induce TILs and activate cytotoxic T cells (CTLs), but these effects were limited. The combination treatment of 125I seeds with Ag+DC administration inhibited primary tumor growth and significantly prolonged survival time in association with a significant increase in T-cell proliferation and interferon-γ release. In addition, triple-combination treatment with αPD1-ab amplified these responses, leading to significant regression of primary and metastatic tumors and successful stimulation of immunological memory. Conclusions: 125I seeds can safely activate anti-tumor immune response.125I seeds combined with Ag+DC administration is able to convert irradiated liver cancer into effective in situ vaccine. Furthermore, triple-combination therapy of 125I seeds, Ag+DC, and αPD1-ab can be a promising approach to activate systemic anti-tumor immunity, which is a potential novel individualized therapy for patients with solid cancers.

Vertebral Augmentation of Cancer-Related Spinal Compression Fractures: A Systematic Review and Meta-Analysis.

Systematic review and meta-analysis. To compare the magnitude and duration of pain relief with vertebral augmentation to any other therapy for the treatment of cancer-related vertebral compression fractures through meta-analysis of randomized controlled trials. Derived from search on PubMed, EMBASE, CINAHL, Scopus, Central, Scopus, and Web of Science databases in May 2020. Studies selected were limited to randomized controlled trials comparing vertebral augmentation, either Balloon Kyphoplasty or Percutaneous Vertebroplasty (PVP) with or without additional therapy to any other intervention or placebo/sham. The methodological quality of each included study was assessed according to the Cochrane Collaboration's domain-based framework. Random effects model, Q test, and I2 statistics were implemented. Of 180 records identified, 7 were considered relevant, and included 476 participants. The risk of bias was considered "Low" in all studies. In five of the studies, vertebral augmentation alone (either PVP or Balloon Kyphoplasty) comprised one group, while comparative treatments included nonsurgical management, Kiva implantation, PVP and radiofrequency therapy, PVP and chemotherapy, PVP and intrasomatic injection of steroid, and PVP with 125I seeds. Two studies compared PVP with an additional therapy against the standard of care. With regard to changes in pain severity, the effect sizes varied from 0.0 (95% -1.7 to 1.7) to -5.1 (95% -5.3 to -4.9). Most studies demonstrated a positive and statistically significant effect associated with PVP. Four of the seven studies demonstrated a clinically significant effect as well. Other than cement leakage, with an event rate of 0.24 (95% CI 0.11-0.44) or 24% (95% CI 11%-44%), there were no major adverse events consistently observed across multiple studies. The included randomized controlled trials demonstrated an overall positive and statistically significant effect of vertebral augmentation surgeries, such as vertebroplasty and kyphoplasty, for the treatment of cancer-related vertebral compression fractures, especially when compared with nonsurgical management, radiofrequency ablation, or chemotherapy alone.Level of Evidence: 1.

Choroidal Melanoma with Ultrasound-Guided Episcleral Brachytherapy: Long-Term Results and Risk of Metastasis

Introduction: The aim of this study was to elucidate the long-term outcomes in patients with choroidal melanoma who received episcleral brachytherapy with 125-I seeds; analyse cause-specific survival (CSS), metastasis-free survival (MFS), and local control; and establish the relationship between tumour size and metastases. Methods: From May 2007 to February 2013, 88 patients classified according to the American Joint Committee on Cancer guidelines underwent ultrasound-guided episcleral brachytherapy with a total prescribed dose of 72.40 Gy to the apex. Results: Among the included cases, 47.7 and 44.3% had a clinical tumour stage of T2 and T3, respectively. With a median follow-up of 84 (range 7–153) months, local control at 5 and 10 years was 100 and 95%, respectively. Among the 88 patients, 9 (10.2%) were enucleated after brachytherapy. Those with T1–T2 and T3–T4 disease had a 10-year CSS of 100 and 87.3%, respectively (p = 0.017). MFS at 5 and 10 years was 100% in those with T1–T2 disease and 92.1 and 83.1% in those with T3–T4, respectively (p = 0.016). Five patients had liver metastases, all of whom had T3–T4 disease. Conclusion: Ultrasound-guided episcleral brachytherapy with 125-I seeds yielded excellent local control for choroidal melanoma, with low complication rates and 90% eye preservation. Given the association between tumour stage and liver metastases, which remain the main cause of death, stricter control should be employed for T3–T4 tumours for the early detection and treatment of relapses.

PO49: Quality Evaluation and Curative Effect Observation of Individualized 3D Printing Template Combined with CT Guided 125I Seed Implantation in the Treatment of Inoperable Limb Soft Tissue Sarcoma

Purpose: To evaluate the dosimetric parameters of 3D printing individualized template combined with CT guided 125I seed implantation, and to explore the efficacy and safety of radioactive 125I seed interstitial implantation in the treatment of unresectable soft tissue sarcoma.

MSOR02 Presentation Time: 10:05 AM: Preliminary Results of 3D Printing Individual Template Assisted CT-Guided Radioactive I-125 Seed Interstitial Brachytherapy as a Salvage Therapy for Recurrent Head and Neck Squamous Carcinoma after External Beam Radiotherapy

MSOR02 Presentation Time: 10:05 AM: Preliminary Results of 3D Printing Individual Template Assisted CT-Guided Radioactive I-125 Seed Interstitial Brachytherapy as a Salvage Therapy for Recurrent Head and Neck Squamous Carcinoma after External Beam Radiotherapy

MSOR02 Presentation Time: 10:05 AM: Preliminary Results of 3D Printing Individual Template Assisted CT-Guided Radioactive I-125 Seed Interstitial Brachytherapy as a Salvage Therapy for Recurrent Head and Neck Squamous Carcinoma after External Beam Radiotherapy

Objective: To investigate the safety and efficacy of 3D-printing non-co-planar template (3D-PNCT)-assisted CT-guided radioactive I-125 seed (RIS) interstitial brachytherapy in the treatment of recurrent head and neck squamous carcinoma after external beam radiotherapy.

PO56: CT-Guided 125I Seed Implantation by Coplanar Template as a Salvage Therapy for Cervical Lymph Node Recurrence of Thoracic Esophageal Squamous Cell Carcinoma after External Beam Radiotherapy

PO56: CT-Guided 125I Seed Implantation by Coplanar Template as a Salvage Therapy for Cervical Lymph Node Recurrence of Thoracic Esophageal Squamous Cell Carcinoma after External Beam Radiotherapy

PO56: CT-Guided 125I Seed Implantation by Coplanar Template as a Salvage Therapy for Cervical Lymph Node Recurrence of Thoracic Esophageal Squamous Cell Carcinoma after External Beam Radiotherapy

Purpose: To analysis outcome and prognosis of computed tomography (CT)-guided 125I seed implantation by coplanar template in patients with cervical lymph node recurrence after multimodal treatment of thoracic esophageal squamous cell carcinoma. The purpose of this study is also to compare the preoperative and postoperative dosimetry of 3D printing coplanar template assisted particle implantation, and to explore the accuracy of this technology in the treatment of radioactive particle implantation.

Miscellaneous PO49: Quality Evaluation and Curative Effect Observation of Individualized 3D Printing Template Combined with CT Guided 125I Seed Implantation in the Treatment of Inoperable Limb Soft Tissue Sarcoma

Miscellaneous PO49: Quality Evaluation and Curative Effect Observation of Individualized 3D Printing Template Combined with CT Guided 125I Seed Implantation in the Treatment of Inoperable Limb Soft Tissue Sarcoma

125I Seed Promotes Apoptosis in Non-small Lung Cancer Cells via the p38 MAPK-MDM2-p53 Signaling Pathway.

Purpose: 125I seeds were effective in the treatment of non-small cell lung cancer in previous research. However, the exact signaling pathway-mediated apoptosis mechanism is still unclear. The present study analyzed the effects and potential mechanisms of 125I seed on the growth and migration of A549 cells.Methods: Lung cancer A549 cells were irradiated with 125I seed for various times. MTT, invasion assay, and flow cytometry were used to detect the proliferation, invasion, and apoptosis of treated cells, respectively. A Nimblegen genome-wide expression profile chip was used to evaluate gene expression changes in 125I seed-treated A549 cells. Validation studies were performed using phosphorylated protein chip technology, Western blot, nude mouse tumor xenograft assay, and immunohistochemical experiments. All statistical analyses were performed using unpaired Student's t tests and Kruskal-Wallis test.Results: Irradiation with 125I seed inhibited A549 cell proliferation and invasion and induced apoptosis (primarily early apoptosis). Irradiation with 125I seed also caused the downregulation of p38MAPK, degradation of mouse double-minute 2 homolog (MDM2), and higher expression of p53, which eventually resulted in non-small cell lung cancer cell apoptosis.Conclusion: 125I seed irradiation activated the p38MAPK/MDM2/p53 signaling pathway and promoted non-small cell lung cancer cell apoptosis. Future clinical studies targeting this signal may provide a new potential therapeutic approach for non-small cell lung cancer.

Prostate permanent implant brachytherapy with BARC I-125 Ocu-Prosta seeds.

The aim of this study is implementation and establishment of standard operating procedure for permanent prostate implant brachytherapy technique using BARC I-125 Ocu-Prosta seeds. The transrectal ultrasound (US)-guided procedure was used for permanent implant procedure. The Best® Sonalis™ US Imaging System and Best NOMOS™ Treatment Planning system was used for volume study and implant procedure. The BARC provided I-125 Ocu-Pro radioactive seeds were implanted into the patient with help of Mick@ Applicator. The implant was performed based on pre-implant dosimetry and intraoperative planning performed during implant procedure. The necessary quality assurance tests were performed for US system before clinical use. The boost dose of 110 Gy was prescribed to the prostate volume of 34.71 cc. About 48 seeds with activity of 0.35 mCi (each) implanted into the prostate volume with reference to intraoperative planning. At the end of procedure, the patient underwent abdomen fluoroscopic examination, to ensure the seed counts in the prostate volume. The day after the implant, the patient was discharged. One month later a planning computed tomography and treatment planning was performed for seed position and dose verification. Low dose rate permanent implant brachytherapy has the advantage of being a one-time procedure and the existing long term follow-up supports its excellent outcome and low morbidity. BARC-BRIT is supplying the loose 125I seeds. These seeds can be easily implanted into the patient using Mick applicator. However, the pre-implant seed preparation and implant procedure may result some radiation exposure to staff involved. The radiation dose can be minimized with good practice. This report is one patient pilot study and intended to test the implant systems and standard operative procedure henceforth for permanent implant brachytherapy procedure.

COMPARISON OF I-125 SEED MARKING AND WIRE MARKING METHODS USED FOR BREAST TUMOR LOCALIZATION

It is very important to accurately determine the location of the lesion in order to accurately excise the tumor area in the breast tissue. The method used to determine the location of the lesion should not only contribute to the precise excision of the lesion, but also help to minimize the loss of healthy tissue during the excision procedure. In addition, the product applied in the localization method to be used before the excision procedure contributes to the success of the operation, as well as the low possibility of complications, contribution to patient satisfaction, ease of application for the practitioner, cost, time saving, ease of coordination and planning between different departments, and reduction of repetition. supplies. However, different localization methods have advantages and disadvantages compared to each other. At this point, the authorized doctor determines the localization method to be applied before the excision of the breast tissue, considering the advantages and disadvantages of different methods. In this study, the method of marking with I-125 Seed, which is used to determine the location of the lesion before excision of the tumor area in the breast tissue, was mentioned and compared with the method of marking with wire, which is an alternative application.

Combined Ultrasound and CT-Guided Iodine-125 Seeds Implantation for Treatment of Residual Hepatocellular Carcinoma Located at Complex Sites After Transcatheter Arterial Chemoembolization.

PurposeThe purpose of this study was to evaluate the efficacy and safety of iodine-125 (125I) seeds implantation under ultrasound and computed tomography (CT) guidance in the treatment of residual hepatocellular carcinoma (HCC) located at complex sites after transcatheter arterial chemoembolization (TACE).MethodsThis retrospective study analyzed the consecutive medical records of 31 HCC patients with residual tumors located at complex sites (such as large blood vessels, gallbladder, diaphragm dome, etc.) after TACE from May 2014 to December 2018, all of whom received 125I seeds implantation therapy. Overall survival (OS), progression-free survival (PFS), recurrence, and complications were documented.ResultsA total of 607 seeds were implanted in 31 patients, with an average of 19.6±10.4 (range, 8–48) seeds per patient. Median OS and PFS were 33 months (95% CI: 27.1 months, 38.9 months) and 15 months (95% CI: 9.6 months, 20.4 months), respectively. Although univariate analysis showed that albumin, prothrombin time, alpha-fetoprotein level, Child-Pugh score, and lipiodol deposition in tumor were associated with OS, multivariate analysis showed that none of them was an independent prognostic factor for OS. Multivariate analysis showed that prothrombin time was an independent prognostic factor for PFS. No operation-related deaths in this study. Although pneumothorax was present in two patients and subcutaneous abscess in one patient, symptoms improved in all three patients with appropriate treatment. Common minor complications included fever, abdominal pain and leukopenia and no grade≥3 adverse events were observed.Conclusions 125I seeds implantation under the combined guidance of ultrasound and CT is safe and effective for patients with residual HCC located at complex sites after TACE. This is a promising treatment approach and deserves further discussion.