The Effectiveness and Prognostic Factors of CT-Guided Radioactive I-125 Seed Implantation for the Treatment of Recurrent Head and Neck Cancer After External Beam Radiation Therapy

125I seed brachytherapy for non-central pelvic recurrence of cervical cancer after external beam radiotherapy

OBJECTIVE

To investigate the efficacy of 125I seed brachytherapy for non-central pelvic recurrence of cervical cancer after external beam radiotherapy, and to analyze the clinical influential factors.

METHODS

Between June 2015 and April 2022, 32 patients with 41 lesions were treated with 125I seed brachytherapy. The seeds were implanted under the guidance of CT and/or 3D-printed template images at a median dose of 100 Gy (range, 80-120 Gy), and the local control rate (LCR) and survival rates were calculated. We used multivariate logistic regression to identify prognosis predictors, and receiver operating characteristic (ROC) curve analysis to determine the optimal cut-off values.

RESULTS

The median follow-up was 48.52 months (range, 4-86 months), and the 6-, 12-, and 24-month LCR was 88.0%, 63.2%, and 42.1%, respectively. The 1- and 2-year survival rates were 36% and 33%, respectively, and the median survival time was 13.26 months. No significant adverse events occurred. Multivariate regression analysis showed that tumor diameter, tumor stage, and LCR were independent factors influencing survival. ROC curve analysis showed that the area under the curve for tumor diameter and D90 were 0.765 and 0.542, respectively, with cut-off values of 5.3 cm and 108.5 Gy.

CONCLUSIONS

The present findings indicate that 125I seed brachytherapy is feasible for treating non-central pelvic recurrence of cervical cancer after external beam radiotherapy. Further, tumor diameter < 5.3 cm and immediate postoperative D90 > 108.5 Gy were associated with better efficacy.

Efficacy of radioactive 125I seed implantation in treating inoperable or refused operation head and neck cancers

PURPOSE

This study aims to observe the curative effect of radioactive 125I seed implantation in treating inoperable or refused operation head and neck cancer.

METHODS

Data from 132 patients with head and neck malignant tumors underwent computed tomography-guided radioactive 125I seed implantation from April 2004 to August 2020 were analyzed retrospectively. The Kaplan-Meier method was used to calculate the local control and survival rates. The logarithmic rank test and the Cox proportional risk model were used for univariate and multivariate analysis, respectively.

RESULTS

A total of 132 patients were enrolled. All tumors were confirmed to be malignant through pathological analysis. Herein, we revealed that the seeds were implanted at the primary tumor site (23 cases, representing 17.4%), recurrent (9 cases, representing 6.8%), or metastatic lymph nodes (100 cases, representing 75.8%). Three months after the operation, 96 patients were evaluated as effective, whereas 36 patients were considered ineffective. The median local control time was 16 months; the local rates at 6, 12, 18, and 24 months were observed to be 75%, 47%, 35%, and 22%, respectively. The study reports a median survival period (OS) of 15 months. Additionally, the survival rates at 6, 12, 18, and 24 months were 61%, 42%, 31%, and 27%, respectively. Regarding side effects, skin or mucosal toxicity occurred in 14 patients. Grade I skin toxicity occurred in seven cases (5.3%), grade IV skin toxicity in one case (0.8%), grade I mucosal ulcer in four cases (3.0%), and grade I dry mouth in four cases (3.0%). The multivariate analysis showed that short-term efficacy and tumor site were independent prognostic factors (P < 0.001, 0.006, respectively). Additionally, the multivariate analysis showed that the independent OS influencing factors included D90, the longest tumor diameter, and short-term efficacy (P = 0.017, 0.001, <0.001).

CONCLUSION

Radioactive 125I seed implantation is a safe and effective salvage therapy for patients with inoperable or refused operation head and neck cancer.

Stereotactic ablative brachytherapy versus percutaneous microwave ablation for early-stage non-small cell lung cancer: a multicenter retrospective study

BACKGROUND

To analyze the efficacy of stereotactic ablative brachytherapy (SABT) and percutaneous microwave ablation (MWA) for the treatment of early-stage non-small cell lung cancer (NSCLC).

METHODS

Patients with early-stage (T1-T2aN0M0) NSCLC who underwent CT-guided SABT or MWA between October 2014 and March 2017 at four medical centers were retrospectively analyzed. Survival, treatment response, and procedure-related complications were assessed.

RESULTS

A total of 83 patients were included in this study. The median follow-up time was 55.2 months (range 7.2-76.8 months). The 1-, 3-, and 5-year overall survival (OS) rates were 96.4%, 82.3%, and 68.4% for the SABT group (n = 28), and 96.4%, 79.7%, and 63.2% for MWA group (n = 55), respectively. The 1-, 3-, and 5-year disease-free survival (DFS) rates were 92.9%, 74.6%, and 54.1% for SABT, and 92.7%, 70.5%, and 50.5% for MWA, respectively. There were no significant differences between SABT and MWA in terms of OS (p = 0.631) or DFS (p = 0.836). The recurrence rate was also similar between the two groups (p = 0.809). No procedure-related deaths occurred. Pneumothorax was the most common adverse event in the two groups, with no significant difference. No radiation pneumonia was found in the SABT group.

CONCLUSIONS

SABT provided similar efficacy to MWA for the treatment of stage I NSCLC. SABT may be a treatment option for unresectable early-stage NSCLC. However, future prospective randomized studies are required to verify these results.

Ultrasmall Gold Nanoparticles Radiolabeled with Iodine-125 as Potential New Radiopharmaceutical

The relatively high linear energy transfer of Auger electrons, which can cause clustered DNA damage and hence efficient cell death, makes Auger emitters excellent candidates for attacking metastasized tumors. Moreover, gammas or positrons are usually emitted along with the Auger electrons, providing the possibility of theragnostic applications. Despite the promising properties of Auger electrons, only a few radiopharmaceuticals employing Auger emitters have been developed so far. This is most likely explained by the short ranges of these electrons, requiring the delivery of the Auger emitters to crucial cell parts such as the cell nucleus. In this work, we combined the Auger emitter 125I and ultrasmall gold nanoparticles to prepare a novel radiopharmaceutical. The 125I labeled gold nanoparticles were shown to accumulate at the cell nucleus, leading to a high tumor-killing efficiency in both 2D and 3D tumor cell models. The results from this work indicate that ultrasmall nanoparticles, which passively accumulate at the cell nucleus, have the potential to be applied in targeted radionuclide therapy. Even better tumor-killing efficiency can be expected if tumor-targeting moieties are conjugated to the nanoparticles.

Automatic planning for head and neck seed implant brachytherapy based on deep convolutional neural network dose engine

BACKGROUND

Seed implant brachytherapy (SIBT) is an effective treatment modality for head and neck (H&N) cancers; however, current clinical planning requires manual setting of needle paths and utilizes inaccurate dose calculation algorithms.

PURPOSE

This study aims to develop an accurate and efficient deep convolutional neural network dose engine (DCNN-DE) and an automatic SIBT planning method for H&N SIBT.

METHODS

A cohort of 25 H&N patients who received SIBT was utilized to develop and validate the methods. The DCNN-DE was developed based on 3D-unet model. It takes single seed dose distribution from a modified TG-43 method, the CT image and a novel inter-seed shadow map (ISSM) as inputs, and predicts the dose map of accuracy close to the one from Monte Carlo simulations (MCS). The ISSM was proposed to better handle inter-seed attenuation. The accuracy and efficacy of the DCNN-DE were validated by comparing with other methods taking MCS dose as reference. For SIBT planning, a novel strategy inspired by clinical practice was proposed to automatically generate parallel or non-parallel potential needle paths that avoid puncturing bone and critical organs. A heuristic-based optimization method was developed to optimize the seed positions to meet clinical prescription requirements. The proposed planning method was validated by re-planning the 25 cases and comparing with clinical plans.

RESULTS

The absolute percentage error in the TG-43 calculation for CTV V100 and D90 was reduced from 5.4% and 13.2% to 0.4% and 1.1% with DCNN-DE, an accuracy improvement of 93% and 92%, respectively. The proposed planning method could automatically obtain a plan in 2.5 ± 1.5 min. The generated plans were judged clinically acceptable with dose distribution comparable with those of the clinical plans.

CONCLUSIONS

The proposed method can generate clinically acceptable plans quickly with high accuracy in dose evaluation, and thus has a high potential for clinical use in SIBT.

Prognostic value of pretreatment FDG PET-CT for short-term efficacy of radioactive iodine-125 seed implantation in patients with NSCLC

PURPOSE

To analyze the short-term clinical response of radioactive iodine-125 seed implantation (I125-SI) in patients of non-small-cell lung cancer (NSCLC) and explore possible correlations of various metabolic parameters of pretreatment FDG PET-CT with the short-term efficacy of this treatment modality.

METHODS AND MATERIALS

The present study is a retrospective analysis of treatment records of 46 NSCLC patients who were treated with I125-SI for lung tumors in Tianjin First Central Hospital from January 2016 to December 2018. The correlation among parameters D90, gender, pathological pattern, age, maximum tumor diameter, Metabolic Tumor Volume (MTV), SUVmax, SUVpeak, SUVmean, Total Lesion Glycolysis (TLG), High metabolic tumor cell ratio (HMR) and Carcinoembryonic antigen(CEA)with short-term efficacy of I125-SI was analyzed by two independent-sample t-test, Mann-Whitney U test or Chi-squared test and binary logistic regression.

RESULTS

After uneventful completion of treatment, patients were followed up at regular intervals. At the first month followup, none of cases showed complete response (CR), while 4 cases showed partial response (PR). After 3 months, there were 2 cases of CR, and 25 cases of PR; after 6 months, there were 5 cases of CR, and 27 cases of PR. D90 (p= 0.028, OR:1.075, 95% CI:1.008-1.147), MTV (p= 0.026, OR: 0.918, 95% CI: 0.851-0.990), HMR (p= 0.020, OR: 0.003, 95% CI: 0-0.407) were independent predictors for the short-term efficacy. The predictive accuracy of MTV was medium (AUC = 0.781; cutoff value = 44.58). However, the predictive accuracies of D90 and HMR were low, with the values of AUC being 0.650 for both the parameters, and their cutoff values being 127.8 Gy and 0.27 respectively.

CONCLUSIONS

I125-SI is an effective therapy with few complications in NSCLC patients. Small MTV, high D90 and low HRM were found to be linked with better local control at 6 months postimplantation.

Safety and efficacy of CT-guided radioactive iodine-125 seed implantation as a salvage treatment for recurrent head and neck cancer after two or more courses of radiotherapy

BACKGROUND

In the past, patients with recurrent head and neck cancer (rHNC) who had previously received a high dose of radiation and were unable to undergo surgery were mainly treated with palliative chemotherapy due to the high incidence of side effects from re-irradiation. With the development of radiotherapy technology, re-irradiation of recurrent lesions by radioactive iodine-125 seed implantation (RISI) has been proposed as a feasible therapeutic approach. This study aimed to investigate the safety and efficacy of computed tomography (CT)-guided RISI in the treatment of rHNC after two or more courses of radiotherapy, and to analyze the prognostic factors.

METHODS

Data of 33 patients with rHNC who received CT-guided RISI after two or more courses of radiotherapy were collected and statistically analyzed. The median cumulative dose of the previous radiotherapy was 110 Gy. Short-term efficacy was assessed by Response Evaluation Criteria in Solid Tumors (version 1.1) criteria, while adverse events were evaluated by Common Terminology Criteria for Adverse Events (version 5.0) criteria.

RESULTS

The median gross tumor volume (GTV) was 29.5 cc, and the postoperative median dose to 90% of target volume (D90) was 136.8 Gy. For adverse reactions, enhanced pain was found in 3 (9.1%) patients, followed by grade 1 to 2 acute skin reactions in 3 (9.1%) patients, grade 2 to 3 late skin reactions in 2 (6.1%) patients, grade 1 to 2 early mucosal reactions in 4 (12.1%) patients, and mandibular osteonecrosis in 1 (3.0%) patient. Regarding the treatment efficacy, the 1- and 2-year local control (LC) rates were 47.8% and 36.4% (median LC time, 10 months), and the 1- and 2-year overall survival (OS) rates were 41.3% and 32.2% (median OS time, 8 months). The absence of adverse events was associated with better LC.

CONCLUSIONS

CT-guided RISI, as a salvage therapy, demonstrated acceptable safety and efficacy in the treatment of rHNC after two or more courses of radiotherapy.

TRIAL REGISTRATION

This study was registered at Chinese Clinical Trial Register database (Registration No. ChiCTR2200063261 ) in September 2, 2022.

125I Radioactive Particles Drive Protective Autophagy in Hepatocellular Carcinoma by Upregulating ATG9B

BACKGROUND AND AIMS

¹²⁵I radioactive particles implantation have demonstrated efficacy in eradicating hepatocellular carcinoma (HCC). However, progressive resistance of HCC to ¹²⁵I radioactive particles has limited its wide clinical application.

METHODS

We investigated the cellular responses to ¹²⁵I radioactive particles treatment and autophagy-related 9B (ATG9B) silencing in HCC cell lines and Hep3B xenografted tumor model using Cell Counting Kit-8 reagent, western blotting, immunofluorescence, flow cytometry, transmission electron microscopy and immunohistochemistry.

RESULTS

In this study, we demonstrated that ¹²⁵I radioactive particles induced cell apoptosis and protective autophagy of HCC in vitro and in vivo. Inhibition of autophagy enhanced the radiosensitivity of HCC to ¹²⁵I radioactive particles. Moreover, ¹²⁵I radioactive particles induced autophagy by upregulating ATG9B, with increased expression level of LC3B and decreased expression level of p62. Furthermore, ATG9B silencing downregulated LC3B expression and upregulated p62 expression and enhanced radiosensitivity of HCC to ¹²⁵I radioactive particles in vitro and in vivo.

CONCLUSIONS

Inhibition of ATG9B enhanced the antitumor effects of ¹²⁵I particle radiation against HCC in vitro and in vivo. Our findings suggest that ¹²⁵I particle radiation plus chloroquine or/and the ATG9B inhibitor may be a novel therapeutic strategy for HCC.

Safety and efficacy of stereotactic ablative brachytherapy as a salvage therapy for recurrent chest wall cancer: A retrospective, multicenter study

Purpose

To evaluate the safety and efficacy of stereotactic ablative brachytherapy (SABT) as a salvage therapy for patients with recurrent chest wall cancer (rCWC) who have previously received external beam radiotherapy (EBRT) or surgery.

Materials and methods

Between November 2013 and October 2020, a total of 130 patients (including 75 men with a median age of 63 years) with rCWC treated with SABT were enrolled in this multicenter retrospective study. There were 97 cases of non-small-cell lung carcinoma, 24 cases of breast cancer, and 9 cases of thymic cancer. Of the patients included, 102 patients previously received surgery and 58 patients received EBRT, with systemic treatment progressing after recurrence. None of them were suitable or refused to undergo salvage EBRT or surgery again.

Results

During the 22 (4-70)-month median patient follow-up, 59 patients died. The local control (LC) rates at 6, 12, 24, and 36 months were 88.3%, 74.3%, 50.4%, and 36.7%, respectively. The 1-, 2- and 3-year survival rates were 85%, 56%, and 42%, respectively. The median overall survival was 26 months (95% CI, 18.9-33.1 months). The pain relief rate was 81%, and the median to remission time was 10 days. Univariate and multivariate analyses showed that independent prognostic factors for LC included tumor size and postoperative D90. On the other hand, independent prognostic factors for survival include the Karnofsky performance status (KPS) score, tumor size, and D90 19 patients (14.6%) developed grade I/II skin reaction complications. No grade III or severer complications occurred.

Conclusion

SABT is safe and effective as a salvage therapy for rCWC following EBRT/surgery. For patients with a KPS score greater than 80, prescribed dose greater than 130 Gy, and tumor size less than 4 cm may bring better results.

Efficacy and toxicity of Iodine-125 seed implantation for lymph node recurrence secondary to esophageal cancer after radiotherapy: a multicenter retrospective study

BACKGROUND/OBJECTIVE

This multicenter study aimed to explore the efficacy and toxicity of radioactive Iodine-125 seed implantation for lymph node recurrence in patients with esophageal cancer after external radiotherapy.

METHODS

Clinical data of eligible patients from 5 centers in China were retrospectively reviewed. A total of 126 patients between January 2016 and March 2019 were included. The median interval between previous radiotherapy and radioactive Iodine-125 seed implantation was calculated. The target volume was 2.1-128.1 cm³ (median, 22.2 cm³) and the median postoperative D90 is 120.6 Gy (range, 101.7-192). Short-term efficacy of tumor response, the long-term efficacy of local progression-free survival (LRFS) and overall survival (OS), and treatment-related toxicity were reported.

RESULTS

For tumor response, 37 (29.4%), 51 (40.5%), 14 (11.1%), and 24 (19.0%) patients achieved complete response, partial response, stable disease and progressive disease, respectively. The 1-, 2- and 3-year LPFS and OS rates were 48.8%, 23.0% and 15.9%, and 80.2%, 38.8%, and 24.5%, respectively. Multivariate analysis identified Karnofsky performance status (P = 0.041) and tumor response (P = 0.049) as independent prognostic factors for LPFS; initial tumor stage (P = 0.034), lesion volume (P = 0.017), and tumor response (P = 0.004) as independent prognostic factors for OS. In total, 77 (61.1%) patients suffered from skin reactions and the incidence of grade 3-5 skin toxicity was 5.6% (7/126).

CONCLUSION

Radioactive Iodine-125 seed implantation seems efficient with acceptable toxicity for the treatment of lymph node recurrence secondary to esophageal cancer. A head-to-head study is needed to further evaluate the survival benefit.

Current radiotherapy for recurrent head and neck cancer in the modern era: a state-of-the-art review

BACKGROUND

In the management of head and neck cancer (HNC) patients, local recurrence is a common cause of treatment failure. Only a few patients with recurrent HNC (rHNC) are eligible for salvage surgery and the majority of patients receive systemic therapy and radiotherapy. In recent years, with the development of irradiation technology, radiotherapy for rHNC patients has markedly attracted clinicians' attention and its therapeutic effects on patients with end-stage cancer are worthy of investigation as well.

METHODS

Several studies have investigated the role of radiotherapy in the treatment of rHNC patients. We reviewed retrospective reports and prospective trials published in recent decades that concentrated on the management of rHNC.

RESULTS

A growing body of evidence supported the application of irradiation to rHNC patients. According to the results of this review, current radiotherapy could achieve a better efficacy with a lower incidence of toxicity.

CONCLUSION

Radiotherapy is a promising treatment for rHNC patients.

The efficacy and safety of 125I brachytherapy combined with pre-operative transarterial chemoembolization in patients with locally advanced head and neck cancer

Objective

To evaluate the safety and effectiveness of Iodine-125 (¹²⁵I) brachytherapy combined with pre-operative transarterial chemoembolization in patients with locally advanced head and neck cancer.

Methods

In this study, a total of thirty-seven individuals suffering from locally advanced head and neck cancer were involved. The patients were subjected to transarterial chemoembolization as well as implantation of ¹²⁵I seeds under the guidance of CT and ultrasonography. Follow-up was conducted for 36 months to study the following parameters: the local control rate, survival rate, and clinical complications.

Results

In total, thirty-six patients at the end of three months showed an objective response rate of 69.8% and disease control rate of 93.0%, respectively. The 1, 2, and 3-year cumulative overall survival rate was 89.2%, 73.0%, and 45.9%, respectively. The adverse events of the treatment included infection (n=1, Grade III), radiation brachial plexus injury (n=1, Grade III), leukopenia (n=1, Grade III), cerebrovascular embolism (n=1, Grade IV).

Conclusion

The combination of ¹²⁵I brachytherapy and pre-operative transarterial chemoembolization was safe and effective in patients with locally advanced head and neck cancer.

Clinical Outcome of CT-Guided Iodine-125 Radioactive Seed Implantation for Intrahepatic Recurrent Hepatocellular Carcinoma: A Retrospective, Multicenter Study

The efficacy and safety of CT-Guided Iodine-125 Radioactive Seed Implantation (RSI) for the treatment of intrahepatic recurrent hepatocellular carcinoma (rHCC) were analyzed in this multicenter retrospective study. We reviewed the medical records of patients with rHCC treated with I-125 seed implantation at four different hospitals in China from December 2011 and January 2021. The local progression-free survival (LPFS),liver PFS, and overall survival (OS) were calculated, and the short-term efficacy and treatment-related toxicities were evaluated. A total of 82 patients were enrolled; the median follow-up time was 46 months (range, 3–80 months). The 1-, 3- and 5-year LPFS rates were 63.8%, 27.1%, and 7.9%, respectively, and the corresponding OS rates were 74.8%, 32.9%, and 12.6%, respectively. Univariate analysis showed that factors influencing LPFS included the maximum lesion diameter, Barcelona Clinic Liver Cancer (BCLC) stage, interval between treatment and recurrence, and D90. Multivariate analyses revealed that the BCLC stage, interval between treatment and recurrence, and D90 were independent factors influencing LPFS, whereas BCLC stage, D90, and short-term efficacy were independent factors influencing OS. In summary, I-125 seed implantation is a safe and effective treatment for rHCC. The BCLC stage, interval, and D90 were found to influence the local control. A larger, prospective study is required to confirm the dose-response curve for Iodine-125 RSI of rHCC.

125I Seed Brachytherapy for Refractory Loco-Regional Recurrence of Non-Anaplastic Thyroid Cancer

Purpose

The purpose of this research was to evaluate the feasibility and efficacy of ¹²⁵I seed brachytherapy as salvage treatment for recurrence from non-anaplastic thyroid cancer refractory to other modalities.

Methods

Between June 2006 and September 2019, fifteen patients with recurrent non-anaplastic thyroid cancer were treated with ¹²⁵I seed brachytherapy. ¹²⁵I seeds were implanted into the tumor under the guidance of CT and/or ultrasound images with the median prescription dose of 120 Gy (range, 100-140 Gy). The median seed number was 80 (range 10-214). Clinical efficacy was evaluated with Response Evaluation Criteria in Solid Tumors.

Findings

Fifteen patients were selected, eleven of whom had papillary carcinoma, two suffered from follicular carcinoma, and two were diagnosed with medullary carcinoma. These patients had twenty-four nodes in total. After they received salvage surgery and/or radioactive iodine (RAI) therapy, local recurrence was detected in all of them. No less than one node was observed in everyone’s cervical or supraclavicular areas, and four patients had lung metastatic. The median follow-up period lasted 48 months (range, 5-93 months). All patients did not develop locoregional recurrence after experiencing ¹²⁵I seed brachytherapy. Only three of them formed new metastases in nontarget regional nodes after brachytherapy, and additional brachytherapy can solve all regional failure problems. No significant adverse events were observed in any patient.

Implications

For the chosen patients, 125I seed brachytherapy is feasible for treating refractory local recurrence from non-anaplastic thyroid cancer. Further studies are required to determine the role of 125I seed brachytherapy in the treatment of thyroid cancer.

Radioactive Iodine-125 in Tumor Therapy: Advances and Future Directions

Radioactive iodine-125 (I-125) is the most widely used radioactive sealed source for interstitial permanent brachytherapy (BT). BT has the exceptional ability to deliver extremely high doses that external beam radiotherapy (EBRT) could never achieve within treated lesions, with the added benefit that doses drop off rapidly outside the target lesion by minimizing the exposure of uninvolved surrounding normal tissue. Spurred by multiple biological and technological advances, BT application has experienced substantial alteration over the past few decades. The procedure of I-125 radioactive seed implantation evolved from ultrasound guidance to computed tomography guidance. Compellingly, the creative introduction of 3D-printed individual templates, BT treatment planning systems, and artificial intelligence navigator systems remarkably increased the accuracy of I-125 BT and individualized I-125 ablative radiotherapy. Of note, utilizing I-125 to treat carcinoma in hollow cavity organs was enabled by the utility of self-expandable metal stents (SEMSs). Initially, I-125 BT was only used in the treatment of rare tumors. However, an increasing number of clinical trials upheld the efficacy and safety of I-125 BT in almost all tumors. Therefore, this study aims to summarize the recent advances of I-125 BT in cancer therapy, which cover experimental research to clinical investigations, including the development of novel techniques. This review also raises unanswered questions that may prompt future clinical trials and experimental work.

Clinical Outcome of CT-Guided Stereotactic Ablative Brachytherapy for Unresectable Early Non-Small Cell Lung Cancer: A Retrospective, Multicenter Study

Objective

To analyze the efficacy and safety of low dose rate stereotactic ablative brachytherapy (L-SABT) for treatment of unresectable early-stage non-small cell lung cancer (NSCLC).

Methods

Data of patients with early-stage NSCLC who received CT-guided L-SABT (radioactive I-125 seeds implantation) at eight different centers from December 2010 to August 2020 were retrospectively analyzed. Treatment efficacy and complications were evaluated.

Results

A total of 99 patients were included in this study. Median follow-up duration was 46.3 months (6.1-119.3 months). The 1-year, 3-year, and 5-year local control rates were 89.1%, 77.5%, and 75.7%, respectively. The 1-year, 3-year, and 5-year overall survival rates were 96.7%, 70.1%, and 54.4%, respectively. Treatment failure occurred in 38.4% of patients. Local/regional recurrence, distant metastasis, and recurrence combined with metastasis accounted for 15.1%, 12.1%, and 11.1%, respectively. Pneumothorax occurred in 47 patients (47.5%) with 19 cases (19.2%) needing closed drainage. The only radiation-related adverse reaction was two cases of grade 2 radiation pneumonia. KPS 80-100, T1, the lesion was located in the left lobe, GTV D90 ≥150 Gy and the distance between the lesion and chest wall was < 1 cm, were associated with better local control (all P < 0.05); on multivariate analysis KPS, GTV D90, and the distance between the lesion and chest wall were independent prognostic factors for local control (all P < 0.05). KPS 80-100, T1, GTV D90 ≥150 Gy, and the distance between the lesion and chest wall was < 1 cm were also associated with better survival (all P < 0.05); on multivariate analysis KPS, T stage, and GTV D90 were independent prognostic factors for survival (all P < 0.05). The incidence of pneumothorax in patients with lesions <1 cm and ≥1cm from the chest wall was 33.3% and 56.7%, respectively, and the differences were statistically significant (P = 0.026).

Conclusion

L-SABT showed acceptable efficacy in the treatment of unresectable early-stage NSCLC. But the incidence of pneumothorax is high. For patients with T1 stage and lesions <1 cm from the chest wall, it may have better efficacy. Prescription dose greater than 150 Gy may bring better results.

Dosimetry verification of three-dimensional printed polylactic acid template-guided precision 125 I seed implantation for lung cancer using a desktop three-dimensional printer

Introduction

The purpose of this study was to verify the effectiveness of polylactic acid (PLA) template puncture route planning by comparing preoperative and postoperative dosimetry using computerized tomography (CT)‐guided implantation of ¹²⁵I radioactive seeds.

Methods

A total of 28 patients who underwent ¹²⁵I seed implantation between January 2018 and June 2019 were selected for the statistical study of seed dosimetry. All patients received preoperative treatment planning system (TPS) planning, of which 13 patients in the experimental 3D template group underwent intraoperative puncture and implantation using the PLA template planning route. The other 15 patients in the traditional control group underwent intraoperative puncture and implantation using CT images for guidance. By calculating the dose‐volume histogram, preoperative and postoperative D90 values and postoperative V90 values were compared between the two groups.

Results

The mean D90 values in the template group before and after surgery were 136.06 ± 7.10 and 134.72 ± 7.85 Gy, respectively. There was no statistically significant difference. The preoperative and postoperative mean D90 values in the traditional group were 132.97 ± 8.04 and 126.06 ± 9.19 Gy, respectively, which were statistically significantly different. The mean postoperative V90 values in the template and traditional groups were 93.80 ± 1.34% and 88.42 ± 6.55 %, respectively, showing a statistically significant difference.

Conclusions

The preoperative TPS plan for the experimental group guided by the PLA template was almost the same as that for the final guided particle implantation. The dose parameters in the experimental group were also better than those in the traditional group, making the use of the presented PLA template more efficient for clinical applications.

Long-Term Outcomes of Personalized Stereotactic Ablative Brachytherapy for Recurrent Head and Neck Adenoid Cystic Carcinoma after Surgery or External Beam Radiotherapy: A 9-Year Study

The management of recurrent head and neck adenoid cystic carcinoma (HNACC) remains a problematic challenge. This study aims to evaluate the long-term outcomes of personalized stereotactic ablative brachytherapy (SABT) as a salvage treatment for recurrent HNACC after surgery or external beam radiotherapy (EBRT). 21 patients with recurrent HNACC after surgery or EBRT successfully underwent iodine-125 (I-125) seed SABT from May 2011 to November 2019. The objective response rate (ORR), disease control rate (DCR), local control time (LCT), overall survival (OS), symptomatic relief and adverse events (AEs) were analyzed. Following SABT, the ORR and DCR were 85.7% and 100%, respectively. The 3-, and 5-year LCT rates were 68.8% and 55.1%, respectively, and the 3- and 5-year OS rates were 85.9% and 66.2%, respectively. Furthermore, univariate analyses showed that higher D90 (>137.1 Gy) was a strong positive prognostic factor of LCT (p < 0.05). The pain disappeared in one patient 3 months after SABT and partial pain improvement was observed in nine patients 1 to 6 months after SABT. Additionally, dyspnea was relieved in one patient with the tumor involving the trachea. The major AEs were mild intraoperative hemorrhage and skin/mucosal toxicities which were generally graded ≤2 and well-tolerated. Personalized SABT was an effective and safe alternative option for recurrent HNACC after the previous failure of surgery or EBRT. The parameter of D90 may influence the local control.

Stereotactic Ablative Brachytherapy: Recent Advances in Optimization of Radiobiological Cancer Therapy

Brachytherapy (BT), a type of focal anti-cancer radiotherapy, delivers a highly focused radiation dose to localized tumors, sparing surrounding normal tissues. Recent technological advances have helped to increase the accuracy of BT and, thus, improve BT-based cancer treatment. Stereotactic ablative brachytherapy (SABT) was designed to improve the ablative effect of radiation, which was achieved via improved image guidance, and calculation of ablative dose, shorter treatment duration, and better organ preservation. Recently collected data characterized SABT as having the potential to cure various early-stage cancers. The method provides higher tumor control rate levels that were previously achievable only by surgical resection. Notably, SABT is suitable for application with unresectable malignancies. However, the pathological assessment of SABT irradiated tumors is limited due to difficulties in specimen acquisition. Prostate, lung, liver, and gynecological cancers are the most commonly reported SABT-treated malignancies. This study will give an overview of SABT, focusing on the advances in SABT optimization, and provide insights on the future benefits of the combined application of SABT with cancer immunotherapies.

Long-Term Safety and Efficacy of CT-Guided I125 Radioactive Seed Implantation as a Salvage Therapy for Recurrent Head and Neck Squamous Carcinoma: A Multicenter Retrospective Study

Purpose

To investigate the safety and efficacy of CT-guided I¹²⁵ radioactive seed implantation (RSI) as a salvage therapy for recurrent head and neck squamous carcinoma (rHNSC) after external beam radiotherapy (EBRT) or surgery.

Materials and Methods

This is a multicenter retrospective study of 113 patients (83 males; median age 57 years) with rHNSC who underwent CT-guided I¹²⁵ RSI between February 2003 and December 2017. Of the included patients, 107 patients previously received EBRT and 65 patients received surgery and all were ineligible or rejected for salvage surgery and/or repeat EBRT.

Results

During a median follow-up duration of 20 months (range, 3-152 months), 87 patients died. The 1-, 2-, 3-, and 5-year local control rate were 57.4%, 41.8%, 29.3%, and 15.2%, respectively. The median time to progression was 15 months [95% confidence interval (CI), 6.1-23.9 months]. The median overall survival (OS) was 20 months (95% CI, 12.4-27.6 months). The 1-, 2-, 3-, and 5-year OS rate were 63.6%, 44.6%, 29.9%, and 21.7%, respectively. Univariate and multivariate analyses revealed that KPS score and postoperative D90 were significantly associated with patients’ OS. The complications were mainly grade I/II skin and mucosal reactions: 18 cases (15.9%) of grade I/II and eight cases (7.0%) of grade III radiation dermatitis, and 14 cases (12.4%) of grade I/II and three cases (2.7%) grade III mucosal reactions. No grade IV or severer complications were found.

Conclusion

CT-guided I¹²⁵ RSI may be safe as a salvage therapy for rHNSC after EBRT/surgery, yielding promising efficacy compared with historical data. KPS score and postoperative D90 may be significantly associated with OS.

The accuracy and dosimetric analysis of 3D-printing non-coplanar template-assisted iodine-125 seed implantation for recurrent chest wall cancer

Purpose

To investigate the accuracy and dosimetry of 3D-printing non-coplanar template (3D-PNCT)-assisted computed tomography (CT)-guided iodine-125 seed implantation (¹²⁵I-SI) for recurrent chest wall cancer (rCWC).

Material and methods

This was a retrospective study of 19 patients with 22 rCWC treated with 3D-PNCT-assisted CT-guided ¹²⁵I-SI, from Mar 2017 to Mar 2020 in our institute.

Results

Mean needle entrance deviation was 4.50 ±2.70 mm, mean angular deviation was 3.40 ±3.10 degrees, and mean depth deviation was 5.20 ±5.20 mm. No significant difference was found for dosimetric parameters (except conformity index) between pre-plan and post-plan; D₉₀, D₁₀₀, V₁₀₀, V₁₅₀, and V₂₀₀ were 157.74 ±24.23 and 151.71 ±33.62 (p = 0.228), 85.36 ±34.09 and 70.46 ±23.48 (p = 0.067), 0.93 ±0.04 and 0.90 ±0.07 (p = 0.068), 0.64 ±0.16 and 0.64 ±0.16 (p = 0.984), and 0.35 ±0.17 and 0.37 ±0.18 (p = 0.382) for pre-plan and post-plan, respectively. Conformity index, external index, and homogeneity index were 0.57 ±0.16 and 0.52 ±0.15 (p = 0.007), 0.73 ±0.55 and 0.79 ±0.53 (p = 0.096), and 0.31 ±0.15 and 0.30 ±0.14 (p = 0.504) for pre-plan and post-plan, respectively. Median follow-up time was 8 months (range, 3-30 months). Complete response was observed in 4/22 (18.1%), partial response in 13/22 (59.1%), stable disease in 4/22 (18.1%), and progression disease in 1/22 (4.5%) of the cancers. Among patients with pain before ¹²⁵I-SI, pain relief rate was 87.5% (7/8). No peri-operative complications of more than grade 2 were observed.

Conclusions

3D-PNCT-assisted CT-guided ¹²⁵I-SI may be safe and feasible as palliative therapy for non-surgical candidates and painful patients with rCWC.

The dosimetry evaluation of 3D printing non-coplanar template-assisted CT-guided 125I seed stereotactic ablation brachytherapy for pelvic recurrent rectal cancer after external beam radiotherapy

The aim of this study was to investigate the safety and accuracy of computed tomography (CT)-guided 125I seed implantation assisted by a three-dimensional printing non-coplanar template (3D-PNCT) for treating pelvic locally recurrent rectal cancer (LRRC) patients. A total of 13 patients with 18 masses received 125I seed implantation. The dosimetric parameters of pre-implantation and post-implantation were calculated to evaluate the quality of 125I seed implantation. Doses delivered to the organs at risk (OAR) were also calculated. Differences between pre-implantation and post-implantation were compared by the paired t-test. The mean number of 125I seeds pre-implantation and post-implantation was 67.1 and 68.8, respectively. The mean values of D90 (dose that was delivered to 90% of the target volume), D100 (dose that was delivered to 100% of the target volume), V100 (the target volume receiving 100% of the prescription dose) and V150 (the target volume receiving 150% of the prescription dose) pre-implantation and post-implantation were 136.6 and 135.2 Gy, 63.5 and 71.0 Gy, 90.3% and 90.3% and 62.1% and 62.2%, respectively. Dosimetric outcomes were evaluated quantitatively using the dose volume indices, i.e. coverage index (CI), external volume index (EI) and relative dose homogeneity index (HI). The mean values of those indices pre-implantation and post-implantation were 0.62 and 0.61, 0.31 and 0.33, and 0.31 and 0.31, respectively. The mean doses delivered to OAR pre-implantation and post-implantation for the bladder (D2cc) and bowel (D2cc) were 33.4 and 34.4 Gy, and 58.6 and 61.8 Gy, respectively. The parameters mentioned above fitted well, and no significant difference was found among them. It is concluded that CT-guided 125I seed implantation assisted by 3D-PNCT could be a safe and accurate salvage modality for treating LRRC patients; the ideal pre-prescription dose could be achieved. Also, addition of 3D-PNCT could minimize radiation damage to the surrounding normal tissues.

The Accuracy of Individualized 3D-Printing Template-Assisted I125 Radioactive Seed Implantation for Recurrent/Metastatic Head and Neck Cancer

Purpose

To evaluate the accuracy of individualized 3D-printing template-assisted I¹²⁵ radioactive seed implantation (3D-PT assisted I¹²⁵ RSI) for recurrent/metastatic head and neck cancer.

Materials and Methods

From February 2017 to January 2020, clinical data of 41 patients (mean age, 58.5 ± 16.1 years; 28 males) with recurrent (48.8%)/metastatic (51.2%) head and neck cancer underwent individualized 3D-PT assisted I¹²⁵ RSI under CT guidance in a single institute were retrospectively reviewed. Total 430 seed needles [mean, 10.5 (range 3–17) per patient] were inserted.

Results

All seed needles were inserted manually in a single attempt with the technical success rate of 100% without major perioperative complications. The mean needle’s entrance deviation was 0.090 cm (95% Confidence Interval, 0.081–0.098). The mean intraoperative depth and angle of the needle were consistent with that of planned (6.23 ± 0.24 vs. 6.21 ± 0.24 cm, p = 0.903; 83.14 ± 3.64 vs. 83.09 ± 3.66 degrees, p = 0.985, respectively). The mean deviation between the needle’s planned and intraoperative depth and angle was 0.168 ± 0.024 cm and 1.56 ± 0.14 degrees, respectively. The postoperative dosimetry parameters, including D90, D100, V100, V150, V200, conformity index, external index, and homogeneity index, were all well-coordinated with planned dosimetry without significant difference (p = 0.515, 0.662, 0.958, 0.865, 0.872, 0.278, 0.456, and 0.989, respectively).

Conclusions

Within the limitation of this study, individualized 3D-PT assisted I¹²⁵ RSI may be accurate in obtaining favorable postoperative dosimetry for patients with recurrent/metastatic head and neck cancer.

Clinical Trial Registration

[website], identifier [registration number].

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

Purpose

The 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).

Methods

This 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.

Results

A 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.

Dosimetric comparison of computed tomography-guided iodine-125 seed implantation assisted with and without three-dimensional printing non-coplanar template in locally recurrent rectal cancer: a propensity score matching study

Purpose

To compare post-implant dosimetric parameters of computed tomography (CT)-guided radioactive iodine-125 (¹²⁵I) seed (RIS) implantation assisted with and without three-dimensional printing non-coplanar template (3D-PNCT) in locally recurrent rectal cancer (LRRC).

Material and methods

One hundred and fifty-five LRRC patients treated by CT-guided RIS implantation assisted with or without 3D-PNCT from October 2003 to May 2019 were included in this study. Propensity score matching (PSM) method (1 : 1) was used to adjust for differences between the 3D-group (with 3D-PNCT) and the CT-group (without 3D-PNCT). After PSM, dosimetric parameters [D₉₀ (dose that covered 90% of target volume), D₁₀₀ (dose that covered 100% of target volume), V₁₀₀ (percentage of gross tumor volume (GTV) receiving 100% of prescription dose), V₁₅₀ (percentage of GTV receiving 150% of prescription dose), HI (homogeneity index), CI (conformity index), and EI (external index)] of the two groups were compared.

Results

After PSM, 45 pairs of matched cases were selected for analysis and differences in variables between the two groups were balanced. For the 3D-group, median values of D₉₀, D₁₀₀, V₁₀₀, V₁₅₀, EI, and HI were 142.6 Gy (73.7-218.2 Gy), 73.7 Gy (26.2-169.3 Gy), 94.1% (74.3-100%), 71.8% (35.4-98.3%), 0.7 (0.1-30.7), and 0.20 (0-0.60), respectively, and corresponding values were 119.9 Gy (39.8-159.3 Gy), 47.0 Gy (13.0-200.9 Gy), 89.9% (38.6-100%), 62.8% (14.8-100%), 0.39 (0-11.01), and 0.30 (0-0.95), respectively, for the CT-group. Parameters including D₉₀, D₁₀₀, V₁₀₀, V₁₅₀, and EI in the 3D-group were significantly higher than those in the CT-group (p < 0.001, p < 0.001, p < 0.001, p < 0.001, and p = 0.006, respectively).

Conclusions

3D-PNCT can improve the accuracy of radioactive seed implantation by increasing the dose delivered to the tumor and reducing the number of “cold” spots of dose.

Accuracy and dosimetric parameters comparison of 3D-printed non-coplanar template-assisted computed tomography-guided iodine-125 seed ablative brachytherapy in pelvic lateral recurrence of gynecological carcinomas

Purpose

To investigate the accuracy of needle distribution and dosimetric parameter differences of 3D-printing non-coplanar template (3D-PNCT)-assisted computed tomography (CT)-guided iodine-125 seed ablative brachytherapy (¹²⁵I-SAB) in gynecological cancer patients with non-central pelvic recurrence between pre-operative plan and post-operative plan.

Material and methods

Thirty-eight patients with forty-one non-central pelvic recurrent gynecological carcinomas after radiotherapy were enrolled in this study. All patients received 3D-PNCT-assisted CT-guided ¹²⁵I-SAB from January 2016 to January 2019. The position, angle, and depth of seed needles were measured in both pre-operative plan and intra-operative real-time plan in brachytherapy treatment planning system (B-TPS). Dosimetric parameters of D₉₀, D₁₀₀, V₁₀₀, V₁₅₀, and V₂₀₀ as well as quality parameters of conformal index (CI), external index (EI), and homogeneity index (HI) were compared between pre-operative plan and post-operative plan. Peri-operation complications and radiation-related toxicity were assessed.

Results

Median follow-up time was 12 months (range, 5-34 months). Prescribed dose was 100-170 Gy (median, 120 Gy). Radioactivity of ¹²⁵I seed was 0.4-0.7 mCi (median, 0.55 mCi). Mean depth deviation for 499 needles was 0.8 ±1.0 cm. Mean angular deviation was 2.2 ±2.1 degrees. Mean tip distance deviation of needles was 0.4 ±0.3 cm. There were significant differences between pre-operative and post-operative plans in CI (p = 0.001) and EI (p = 0.005). No significant differences were shown in D₉₀, D₁₀₀, V₁₀₀, V₁₅₀, V₂₀₀, and HI between pre-operative and post-operative plans. Only few patients suffered from ≤ grade 2 toxicities.

Conclusions

3D-PNCT-assisted CT-guided ¹²⁵I-SAB is safe and feasible for non-central pelvic recurrence of gynecological cancer. All complications are tolerable and mild.

The effectiveness and prognostic factors of radioactive iodine-125 seed implantation for the treatment of cervical lymph node recurrence of esophageal squamous cell carcinoma after external beam radiation therapy

Purpose

To analyze factors influencing the efficacy of ¹²⁵I seed implantation in the treatment of in-field cervical lymph node recurrence of esophageal squamous cell carcinoma (ESCC) after external beam radiation therapy.

Material and methods

We conducted a retrospective review of 36 patients with in-field cervical metastatic lymph nodes recurrence of esophageal squamous cell carcinoma (CML-ESCC) after external beam radiation therapy treatment, who underwent ¹²⁵I seed implantation in our department from 2013 to 2019. Previous cumulative external irradiation dose ranged from 20 to 66 Gy (median, 60 Gy). The post-implant efficacy was evaluated by response evaluation criteria in solid tumors (RECIST) version 1.1, and an adverse event was evaluated by the Radiation Therapy Oncology Group (RTOG)/European Organization for Research and Treatment of Cancer Late Radiation Morbidity Score (EORTC). COX proportional hazards model was used to analyze risk factors affecting effectiveness.

Results

Among 36 patients, 31 patients (86.1%) received fluorouracil-based chemotherapy (1-6 cycles) after ¹²⁵I seed implantation. Local control rates at 3, 6, 12, and 24 months after implantation were 51%, 30%, 30%, and 18%, respectively, with a median of 9 months (95% CI: 6.106-11.894); survival rates after 3, 6, 12, and 24 months were 55%, 41%, 22%, and 22%, respectively, with a median of 8 months (95% CI: 5.753-10.247). Multivariate analysis showed that D₉₀ and short-term efficacy were independent factors related to local control and survival rate (p = 0.005, < 0.001, 0.010, < 0.001). There were 2 cases (5.6%) with grade 1 skin toxicity, 1 case (2.8%) with grade 4 skin toxicity, 3 cases (8.3%) with grade 1 mucosal ulcer, and 3 cases (8.3%) with grade 1 xerostomia.

Conclusions

¹²⁵I seed implantation as an effective salvage treatment shows definite efficacy and safety for patients with in-field cervical lymph node recurrence of ESCC after external beam radiation therapy.

Safety and efficacy of 3D-printed templates assisted CT-guided radioactive iodine-125 seed implantation for the treatment of recurrent cervical carcinoma after external beam radiotherapy

Objective

To investigate the safety and efficacy of 3-dimensional (3D) printing non-coplanar templates (PNCT) assisted computer tomography (CT) guided radioactive ¹²⁵I seed implantation (RISI) for the treatment of recurrent cervical carcinoma (RCC) after external beam radiotherapy (EBRT).

Methods

A total of 103 patients with inoperable post-EBRT RCC were included in this retrospective study. A total of 111 lesions received RISI. Eight lesions were at the pelvic center, 75 lesions were at the pelvic lateral, and 28 lesions were extra-pelvic metastasis. The median prescription dose was 120 Gy. The primary end points were adverse events and local control (LC), and the secondary end points were overall survival (OS) and progression-free survival.

Results

Grade 2 adverse events of acute nausea, diarrhea, and pollakiuria occurred in 1, 2, and 1 patient, respectively. One patient suffered from grade 3 acute proctitis. Late toxicity was observed in 2 patients with rectovaginal fistula. No grade 5 toxicity occurred. The 3-year LC and OS rates were 75.1% and 20.8%, respectively. The median OS was 17 months. The multivariate analysis showed that the minimum dose received by the “hottest” 90% of the gross tumor volume (D₉₀) ≥130 Gy, squamous cell carcinoma, hemoglobin ≥80 g/L and good short-term efficacy (complete response or partial response) were independent predictors of LC and OS (all p<0.05).

Conclusions

3D-PNCT assisted CT-guided RISI is a safe, effective, and minimally invasive modality for RCC. The hemoglobin level, pathological type, dose distribution and short-term efficacy are considered as independent factors for clinical outcomes.

Auger Electrons Constructed Active Sites on Nanocatalysts for Catalytic Internal Radiotherapy

Excess electrons play important roles for the construction of superficial active sites on nanocatalysts. However, providing excess electrons to nanocatalysts in vivo is still a challenge, which limits the applications of nanocatalysts in biomedicine. Herein, auger electrons (AEs) emitted from radionuclide 125 (125I) are used in situ to construct active sites in a nanocatalyst (TiO2) and the application of this method is further extended to cancer catalytic internal radiotherapy (CIRT). The obtained 125I-TiO2 nanoparticles first construct superficial Ti3+ active sites via the reaction between Ti4+ and AEs. Then Ti3+ stretches and weakens the O-H bond of the absorbed H2O, thus enhancing the radiolysis of H2O molecules and generating hydroxyl radicals (•OH). All in vitro and in vivo results demonstrate a good CIRT performance. These findings will broaden the application of radionuclides and introduce new perspectives to nanomedicine.

Dosimetry, efficacy, and safety of three-dimensional printing noncoplanar template-assisted and CT-guided 125I seed implantation for recurrent retroperitoneal lymphatic metastasis after external beam radiotherapy

OBJECTIVES

To evaluate the dosimetry, efficacy, and safety of radioactive ¹²⁵I seed implantation (RISI) assisted by three-dimensional printing noncoplanar template (3D-PNCT) and CT for recurrent retroperitoneal lymphatic metastasis (RRLM) after previous external beam radiotherapy.

METHODS AND MATERIALS

From June 2016 to August 2018, 32 patients with RRLM successfully underwent 3D-PNCT-assisted and CT-guided RISI. The dosimetry, pain relief rate, performance improvement rate, overall response rate, disease control rate, local control time (LCT), overall survival (OS), and safety profiles were evaluated.

RESULTS

Dosimetric results showed that the D90, D100, V100, V150, V200, and homogeneity index were consistent in preoperation and postoperation (p > 0.05), except for the external index and conformal index (p = 0.048, p = 0.034). After RISI, 81.3% of the patients achieved pain relief, and 71.9% achieved an improvement of performance. The overall response rate and disease control rate were 85.3% and 94.1%, respectively. The LCT rates reached 66.2% and 43.2% in 1 year and two years, respectively, with a median LCT of 15.8 months. The OS rates were 74.1% and 28.1% in 1 year and two year, respectively, with a median OS reaching 17.6 months. Univariate analysis showed that when D90 > 130 Gy or D100 > 63 Gy or tumor size ≤49.8 cm³, LCT was extended significantly, but not for OS. Except for two patients developing Grade 1 retroperitoneal hematomas, no other severe adverse events were observed.

CONCLUSIONS

3D-PNCT and CT guidance provide excellent accuracy for RISI, which can be an effective and safe alternative for RRLM after external beam radiotherapy. Radiation dose and tumor size seem to significantly influence the local control.

Significance of 125I radioactive seed implantation on growth differentiation factor and programmed death receptor-1 during treatment of oral cancer

BACKGROUND

Oral cancer (OC) is the most common malignant tumor in the oral cavity, and is mainly seen in middle-aged and elderly men. At present, OC is mainly treated clinically by surgery or combined with radiotherapy and chemotherapy; but recently, more and more studies have shown that the stress trauma caused by surgery and the side effects of radiotherapy and chemotherapy seriously affect the prognosis of patients.

AIM

To determine the significance of ¹²⁵I radioactive seed implantation on growth differentiation factor 11 (GDF11) and programmed death receptor-1 (PD-1) during treatment of OC.

METHODS

A total of 184 OC patients admitted to The Second Affiliated Hospital of Jiamusi University from May 2015 to May 2017 were selected as the research subjects for prospective analysis. Of these patients, 89 who received ¹²⁵I radioactive seed implantation therapy were regarded as the research group (RG) and 95 patients who received surgical treatment were regarded as the control group (CG). The clinical efficacy, incidence of adverse reactions and changes in GDF11 and PD-1 before treatment (T0), 2 wk after treatment (T1), 4 wk after treatment (T2) and 6 wk after treatment (T3) were compared between the two groups.

RESULTS

The efficacy and recurrence rate in the RG were better than those in the CG (P < 0.05), while the incidence of adverse reactions and survival rate were not different. There was no difference in GDF11 and PD-1 between the two groups at T0 and T1, but these factors were lower in the RG than in the CG at T2 and T3 (P < 0.05). Using receiver operating characteristic (ROC) curve analysis, GDF11 and PD-1 had good predictive value for efficacy and recurrence (P < 0.001).

CONCLUSION

¹²⁵I radioactive seed implantation has clinical efficacy and can reduce the recurrence rate in patients with OC. This therapy has marked potential in clinical application. The detection of GDF11 and PD-1 in patients during treatment showed good predictive value for treatment efficacy and recurrence in OC patients, and may be potential targets for future OC treatment.

Efficacy and safety of CT-guided 125I seed implantation as a salvage treatment for locally recurrent head and neck soft tissue sarcoma after surgery and external beam radiotherapy: A 12-year study at a single institution

OBJECTIVES

The objective of this study was to evaluate the efficacy and safety of CT-guided radioactive ¹²⁵I seed implantation as a salvage treatment for locally recurrent head and neck soft tissue sarcoma (HNSTS) after surgery and external beam radiotherapy.

METHODS AND MATERIALS

From December 2006 to February 2018, 25 patients with locally recurrent HNSTS after surgery and external beam radiotherapy were enrolled. All the patients successfully underwent CT-guided ¹²⁵I seed implantation. The primary end points included the objective response rate (ORR) and local progression-free survival (LPFS). The secondary end points were survival (OS) and safety profiles.

RESULTS

After ¹²⁵I seed implantation, the ORR was 76.0%. The 1-, 3-, and 5-year LPFS rates were 65.6%, 34.4%, and 22.9%, respectively, with the median LPFS of 16.0 months. The 1-, 3-, and 5-year OS rates were 70.8%, 46.6%, and 34.0%, respectively, with the median OS of 28.0 months. Furthermore, univariate analyses showed that the recurrent T stage and histological grade were prognostic factors of LPFS, whereas only the histological grade was a predictor of OS. The major adverse events were skin/mucosal toxicities, which were generally of lower grade (≤Grade 2) and were well tolerated.

CONCLUSIONS

Radioactive ¹²⁵I seed implantation could be an effective and safe alternative treatment for locally recurrent HNSTS after failure of surgery and radiotherapy. Recurrent T stage and histological grade were the main factors influencing the efficacy.