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

Efficacy and safety of 3-dimensional printing noncoplanar template (3D-PNCT)-assisted high-dose-rate interstitial brachytherapy (HDR-ISBT) for reirradiation of recurrent cervical cancer: a prospective cohort

OBJECTIVE

This study aimed to investigate the efficacy and safety of 3-dimensional printing noncoplanar template (3D-PNCT)-assisted computed tomography (CT)-guided high-dose-rate interstitial brachytherapy (HDR-ISBT) for reirradiation of pelvic recurrent cervical carcinoma after external beam radiotherapy.

METHODS

From January 2019 to August 2023, 45 eligible patients were enrolled in this prospective cohort. All patients underwent 3D-PNCT-assisted CT-guided HDR-ISBT with a prescribed dose of 4-7 Gy/fraction to the high-risk clinical target volume (HR-CTV) over 3-8 fractions, either for curative or palliative purposes. The primary endpoints were local progression-free survival (LPFS) and tumor response rate (TRR). The secondary outcome measures included overall survival (OS), toxicities, and symptom resolution.

RESULTS

Forty-five patients received 261 fractions of 3D-PNCT-assisted HDR-ISBT. Twenty-nine patients had isolated pelvic recurrence, and 16 patients had simultaneous extra-pelvic or distant recurrences. The TRR was 66.7%. The 2- and 5-year LPFS rates were 30.0% and 25.7%, respectively. The median OS was 23.2 months, and 2- and 5-year OS rates were 49.5% and 34.0%, respectively. The multivariate analysis indicated that squamous cell carcinoma, radical surgery, recurrence-free interval≥12 months, tumor diameter, pelvic recurrence type, and HR-CTV D90≥45 Gy were independent factors influencing LPFS (all p<0.05). D100≥21 Gy, V100≥83%, and V150≥45% were associated with better LPFS (all p<0.05). Tumor diameter and metastasis were independent predictive factors for OS (all p<0.05). The pain relief rate was 66.7% (10/15). Grade 3-4 toxicities occurred in 20.0% of patients.

CONCLUSION

3D-PNCT-assisted HDR-ISBT for reirradiation of recurrent cervical cancer proved to be an effective and safe alternative to radical surgery.

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.

Chemotherapy alone versus chemotherapy plus 125I brachytherapy for the second-line treatment of locally recurrent cervical cancer after/with radical treatment: A propensity score analysis

Rationale and objectives

The primary aim of this study was to conduct a retrospective comparative analysis of the survival outcomes in patients with recurrent cervical cancer (CC). Specifically, we aimed to compare the efficacy of chemotherapy alone versus the combined approach of chemotherapy and 125I brachytherapy subsequent to the failure of initial chemotherapy treatment.

Materials and methods

Patients diagnosed with recurrent CC subsequent to the failure of initial chemotherapy from January 2007 to December 2016 were enrolled from 2 hospitals. These patients were then divided into two groups: Group A, which underwent second-line chemotherapy alone, and Group B, which received both second-line chemotherapy and 125I brachytherapy. The assessment of overall survival (OS) and progression-free survival (PFS) was carried out through propensity score matching (PSM) (1:1), Kaplan-Meier curves, log-rank tests, and Cox proportional hazard regression for survival analysis.

Results

A matched cohort comprising 88 patients each in Group A and Group B was included in the study. In Group A, the 1-, 2-, and 3-year cumulative PFS rates were 40.9 %, 15.9 %, and 5.7 % respectively, while in Group B, these rates were significantly higher at 79.5 %, 48.9 %, and 25.0 % (P = 0.003). Similarly, the 1-, 2-, and 3-year cumulative OS rates among Group A were 67.0 %, 27.3 %, and 5.7 % compared to 89.8 %, 63.6 %, and 30.7 % among Group B, suggesting a difference with statistical significance (P < 0.001) between the two groups. Moreover, the incidence of complications was similar between groups (P = 0.698).

Conclusions

Our findings suggest that the combined approach of chemotherapy and 125I brachytherapy yields superior therapeutic effects but similar complication rates compared to chemotherapy alone in patients experiencing local recurrence of CC following failed initial chemotherapy.

Radiotherapy for postoperative vaginal recurrences of cervical squamous cell carcinoma: analysis of dosing and prognosis

Squamous cell carcinoma (SCC) is the most common type of vaginal recurrence in cervical cancer patients, and the role of salvage radiotherapy on these patients remains unclear. This study aimed to investigate the efficacy of salvage radiotherapy for vaginal recurrence of SCC in patients who previously underwent surgery and to explore prognostic factors associated with survival. Ninety-seven patients with histologically proven SCC who were treated for vaginal recurrence at Peking Union Medical College Hospital were identified. All patients had previously undergone surgery and received salvage radiotherapy. Factors predictive of overall survival (OS), progression-free survival (PFS), and local control (LC) were investigated. The median follow-up time was 42.5 months. The estimated 5-year OS, PFS, and LC rates were 84%, 79%, and 91%. On multivariate analysis, inguinal lymph node metastasis was significantly associated with poor OS; a tumour size ≤4 cm was associated with longer PFS (p < 0.05); the recurrence pattern was an independent predictor of LC (p < 0.05). In the 45 patients with recurrences that were paravaginal or invasive of surrounding organs, biologically equivalent doses in 2 Gy fractions of ≥72.6 Gy were independently predictive of longer LC (p < 0.05). RT is an effective treatment for postoperative vaginal recurrence in patients with cervical SCC. For patients with extravaginal recurrence, a salvage dose of ≥72.6 Gy appears to be optimal.Impact statementWhat is already known on this subject? Radiotherapy plays a critical role in treating recurrent cervical cancer, but the effectiveness of RT for vaginal recurrence in patients who previously underwent surgery remains limited. Few studies have focussed on the effect of RT dose on patient survival.What do the results of this study add? This study investigated the efficacy of RT in patients with cervical squamous cell carcinoma who experienced postoperative recurrence. Lymph node metastasis, tumour size and recurrence pattern were significantly associated with survival. Moreover, an EQD2 ≥ 72.6 Gy was independently predictive of longer LC.What are the implications of these findings for clinical practice and/or further research? RT is an effective treatment for postoperative vaginal recurrence in patients with cervical squamous cell carcinoma. For patients with extravaginal recurrence, a salvage dose of ≥72.6 Gy appears to be optimal.

Feasibility of 125I brachytherapy combined with arterial infusion chemotherapy in patients with advanced pancreatic cancer

To evaluation the feasibility of Iodine-125 (¹²5I) brachytherapy combined with arterial infusion chemotherapy in patients with advanced pancreatic cancer. A total of 72 cases with Stage III and IV were retrospectively reviewed. 23 cases receiving 125I brachytherapy were classified as Group A. 27 cases receiving arterial infusion chemotherapy (gemcitabine + cisplatin, GP) were classified as Group B and 22 cases receiving 125I brachytherapy combined with arterial infusion chemotherapy (GP) were classified as Group C. The evaluated indications were local control rate, survival rate, carbohydrate antigen 19-9, pain relief, and Karnofsky physical scores. Analysis of Variancep, Pearson chi-square test and Kaplan-Meier curves were used for analysis. The local control rate of group A and group C was significantly higher than group B (P < .001). Pearson chi-square test showed statistical difference of the 3 groups (χ2 = 12.969, P = .044). The median survival of group A,B and C was 9 months, 6 months and 13 months, respectively. The survival time of group C was significantly higher than group B (χ2 = 5.403, P = .020). The Log rank test showed statistical difference in the survival curve of the 3 groups (χ2 = 6.501, P = .039). The difference of carbohydrate antigen 19-9 decline percentage between group B and C group was statistically significant (χ2 = 5.959, P = .015). Patients in group A and group C relieved form pain after treatment with statistically significant (P < .001). Pain relief was much more effective in patients who received 125I brachytherapy. Karnofsky physical scores after treatment were statistically higher than those before treatment in each group (P < .001). 125I brachytherapy maybe one of the effective, safe and feasible alternative treatment of advanced pancreatic cancer. ¹²5I brachytherapy combined with arterial infusion chemotherapy was effective in the treatment of advanced pancreatic cancer.

Dosimetric parameters and safety analysis of 3D-printing non-coplanar template-assisted interstitial brachytherapy for non-centrally recurrent cervical cancer

Introduction

The prognosis of patients with non-central recurrent cervical cancer (NRCC) remains poor, and treatment options are limited. We aimed to explore the accuracy and safety of the 3D-printed non-coplanar template (3D-PNCT)-assisted 192Ir interstitial brachytherapy (ISBT) in the treatment of NRCC.

Material and methods

A total of 36 patients with NRCC who received 3D-PNCT-guided 192Ir ISBT in the First Affiliated Hospital of Zhengzhou University from January 2021 to July 2022 were included in this study. There were 36 3D-PNCTs that were designed and printed. The prescribed dose was 30-36 Gy, divided into five to six times, once a week. To evaluate whether the actual parameters were consistent with the preoperative design, the dosimetric parameters of pre- and postoperative treatment plans were compared, including dose of 90% high-risk clinical target volume (HR-CTV D90), volume percentage of 100% and 150% prescribed dose V100% and V150%, homogeneity index (HI), conformal index (CI), external index (EI), and dose received by 2 cm3 (D2cm3) of the rectum, colon, bladder, and ileum. The safety parameters including occurrence of bleeding, infection, pain, radiation enteritis, and radiation cystitis within 3 months after operation were recorded.

Results

All patients successfully completed the treatment and achieved the goals of the preoperative plan. There was no significant difference in the accuracy (HRCTVD90, V100%, EI, CI, and HI) and safety (D2cm3 of rectum, colon, bladder, and ileum) parameters of the postoperative plan compared with the preoperative plan (all p>0.05). Major side effects included bleeding at the puncture site (13.9%), postoperative pain (8.3%), acute radiation cystitis (13.9%), and radiation enteritis (19.4%). There were no serious perioperative complications and no grade 3-4 acute radiotherapy side effects.

Conclusion

3D-PNCT-assisted 192Ir ISBT can be accurately and safely applied in the treatment of patients with NRCC.

The Use of 3D Printing Technology in Gynaecological Brachytherapy-A Narrative Review

Radiation therapy, including image-guided adaptive brachytherapy based on magnetic resonance imaging, is the standard of care in locally advanced cervical and vaginal cancer and part of the treatment in other primary and recurrent gynaecological tumours. Tumour control probability increases with dose and brachytherapy is the optimal technique to increase the dose to the target volume while maintaining dose constraints to organs at risk. The use of interstitial needles is now one of the quality indicators for cervical cancer brachytherapy and needles should optimally be used in ≥60% of patients. Commercially available applicators sometimes cannot be used because of anatomical barriers or do not allow adequate target volume coverage due to tumour size or topography. Over the last five to ten years, 3D printing has been increasingly used for manufacturing of customised applicators in brachytherapy, with gynaecological tumours being the most common indication. We present the rationale, techniques and current clinical evidence for the use of 3D-printed applicators in gynaecological brachytherapy.

Iodine-125 seed implantation in the treatment of malignant tumors

Malignant tumors are major causes of morbidity and mortality in China. Despite advances in surgical, radiological, chemotherapeutic, molecular targeting, and immunotherapeutic treatments, patients with malignant tumors still have poor prognoses. Low-dose-rate brachytherapy, specifically 125I seed implantation, is beneficial because of its high local delivery dose and minimal damage to surrounding tissues. Consequently, it has gained increasing acceptance as a treatment modality for various malignant tumors. In this study, we explored the fundamental principles, clinical applications, and new technologies associated with 125I radioactive seed implantation.

3D printing in brachytherapy: A systematic review of gynecological applications

PURPOSE

To provide a systematic review of the applications of 3D printing in gynecological brachytherapy.

METHODS

Peer-reviewed articles relating to additive manufacturing (3D printing) from the 34 million plus biomedical citations in National Center for Biotechnology Information (NCBI/PubMed), and 53 million records in Web of Science (Clarivate) were queried for 3D printing applications. The results were narrowed sequentially to, (1) all literature in 3D printing with final publications prior to July 2022 (in English, and excluding books, proceedings, and reviews), and then to applications in, (2) radiotherapy, (3) brachytherapy, (4) gynecological brachytherapy. Brachytherapy applications were reviewed and grouped by disease site, with gynecological applications additionally grouped by study type, methodology, delivery modality, and device type.

RESULTS

From 47,541 3D printing citations, 96 publications met the inclusion criteria for brachytherapy, with gynecological clinical applications compromising the highest percentage (32%), followed by skin and surface (19%), and head and neck (9%). The distribution of delivery modalities was 58% for HDR (Ir-192), 35% for LDR (I-125), and 7% for other modalities. In gynecological brachytherapy, studies included design of patient specific applicators and templates, novel applicator designs, applicator additions, quality assurance and dosimetry devices, anthropomorphic gynecological applicators, and in-human clinical trials. Plots of year-to-year growth demonstrate a rapid nonlinear trend since 2014 due to the improving accessibility of low-cost 3D printers. Based on these publications, considerations for clinical use are provided.

CONCLUSIONS

3D printing has emerged as an important clinical technology enabling customized applicator and template designs, representing a major advancement in the methodology for implantation and delivery in gynecological brachytherapy.

Tolerance limit of external beam radiotherapy combined with low-dose rate brachytherapy in normal rabbit tissue

BACKGROUND

Dosage-optimized multimodal radiotherapies that are safe for head and neck cancer patients are desirable. In this study, we investigated tissue tolerance to varying doses of external beam radiotherapy (EBRT) combined with low-dose rate brachytherapy in the neck of a rabbit model.

METHODS

Twenty rabbits were used in the four test groups (five each) with iodine-125 seeds implanted in the neck treated with EBRT in four doses at 50, 40, 30 and 20 Gy each. Twelve rabbits for three control groups (four each). Three months after implantation, all rabbits were euthanized, and target tissues were collected. Analyses included seed implantation assessment, histopathological evaluation, immunohistochemistry staining, terminal deoxynucleotidyl transferase dUTP nick end labeling assay, electron microscopy and statistics with the SPSS software.

RESULTS

Five rabbits died in the four test groups, and three rabbits died in the three control groups (one per group), which showed no significant difference by survival analysis. The calculated minimum peripheral dose was 17.6 Gy, the maximum dose near the seed was 1812.5 Gy, the D90 was 34.5 Gy and the mean dose was 124.5 Gy. In all groups that received radiation, apoptosis occurred primarily in the esophageal mucosa and corresponded to the dose of radiation; a higher dose caused a greater apoptosis, with significant difference between groups (P < 0.05). Electron microscopy of carotid arteries revealed that endothelial cells were swollen and some were shed from basement membrane, but no other noticeable tissue damages.

CONCLUSIONS

Limited EBRT at maximal dose (50 Gy) combined with the brachytherapy interstitially applied to the neck was tolerated well in the rabbit model.

Locoregional therapy for oligometastatic cervical cancer: a single-center retrospective study

BACKGROUND

Oligometastases are limited in number and extent, and therefore, are amenable to locoregional therapy.

OBJECTIVE

To analyze recurrence patterns, survival outcomes, and prognostic factors in patients with cervical cancer receiving locoregional therapy for oligometastases.

METHODS

The included patients had 1-3 extracranial oligometastases and received definitive radiotherapy, surgery, or ablation at a single institution between January 2007 and May 2022. Outcomes were evaluated using the Kaplan-Meier method. Prognostic factors were examined using the Cox proportional hazards model, and tumor growth rates were predicted by non-linear regression.

RESULTS

We identified 56 patients who presented with an oligometastatic disease to the supraclavicular fossa (n=19), lung (n=33), or other sites (n=4). Totals of 30 (53.6%), 41 (73.2%), 47 (83.9%), and 52 (92.9%) patients were diagnosed 1, 2, 3, and 4 years after cervical cancer diagnosis, respectively. Seven patients were simultaneously treated for para-aortic or pelvic recurrences. After a median follow-up of 24 months (range 1-86), the 3-year local recurrence-free rate in patients with supraclavicular versus non-supraclavicular oligometastases was 100% vs 93.5%. The 3-year overall survival rate was 40.1% vs 55.2% (p=0.04). Ten (17.9%) patients experienced new oligometastatic progression in a median of 8 months (range 4-14). Multivariate analysis showed that tumor size was the only prognostic factor for overall survival, with a 3-year overall survival rate of 91.7% vs 21.6% (≤15 mm vs >15 mm, p<0.001). Nineteen (86.4%) of 22 lesions diagnosed within 6 months of the last negative CT scan had a maximum diameter of ≤15 mm, and the predicted interval of tumor growth to 15 mm was 5.8 months.

CONCLUSION

Locoregional therapy for cervical cancer oligometastases can achieve long-term survival, especially in patients with small lesions (≤15 mm). Better follow-up mode after cervical cancer treatment and system therapy for oligometastases should be further explored.

Iodine-125 brachytherapy treatment for newly diagnosed brain metastasis in non-small cell lung cancer: A biocentric analysis

Purpose

The aim of the present study is to evaluate the safety and efficacy of iodine-125 brachytherapy for newly diagnosed brain metastasis in patients with non-small cell lung cancer (NSCLC).

Materials and methods

The study included 158 NSCLC patients diagnosed with brain metastasis from December 2003 to August 2017. Ninety-nine patients underwent external beam radiotherapy (EBRT group), and 59 patients received iodine-125 brachytherapy (¹²⁵I group). In addition, the 6- and 12-month progression-free survival (PFS) rates and the 12- and 24-month overall survival (OS) rates were compared between the EBRT group and the ¹²⁵I group. Median OS and PFS were analyzed using the Kaplan-Meier method with a log-rank test.

Results

The 6-month PFS rate was significantly higher in the ¹²⁵I group (p = 0.002) than in the EBRT group, while no differences were found in the 12-month PFS rate (p = 0.184). Additionally, the 12- (p = 0.839) and 24-month (p = 0.284) OS rates were not significantly different between the two groups. No significant differences in median OS (p = 0.525) or PFS (p = 0.425) were found between the two groups.

Conclusions

Iodine-125 brachytherapy is an alternative therapy for patients unable to undergo surgical resection.

A comparative study of dosimetric parameters of 3D-printed non-coplanar template-assisted CT-guided iodine-125 seed implantation brachytherapy in patients with inguinal lymph node metastatic carcinomas

PURPOSE

To compare the pre-plan and post-plan dosimetric parameter differences of 3D-printed non-coplanar templates (3D-PNCT)-assisted computed tomography (CT)-guided iodine-125 (125I) radioactive seed implantation brachytherapy (RISI) in patients with inguinal lymph node metastasis (ILNM).

MATERIAL AND METHODS

This was a retrospective study of 15 patients with ILNM carcinomas treated with 3D-PNCT-assisted CT-guided RISI between May, 2015 and April, 2018. All patients underwent prior external beam radiotherapy (EBRT) or surgery. Dosimetric parameters included D90, D100 (dose delivered to 90% and 100% of the volume, respectively), V100, V150, V200 (percentage of target volume receiving 100%, 150%, and 200% of the prescribed dose, respectively). Quality parameters included conformal index (CI), external index (EI), and homogeneity index (HI). Paired t-test and Bland-Altman analysis were applied to compared pre-plan and post-plan parameters.

RESULTS

The median gross tumor volume (GTV) in the pre-plan was 8.7 ml (range, 0.8-185.1 ml). There were statistically significant differences in V100, V150, CI, and EI (p < 0.05). Bland-Altman analysis indicated that accidental error of RISI was small. In 1 of the 15 cases, D90 and D100 exceeded the prescribed therapeutic accuracy. In 1 of the 15 cases, V150, EI, and GTV were outside the specified accuracy range (95% confidence interval).

CONCLUSIONS

3D-PNCT-assisted CT-guided RISI is a safe, accurate, and feasible choice in ILNM treatment. The procedure of RISI has significantly improved. The pre-plan can be accurately executed by 3D-PNCT-assisted CT-guided RISI.

Re-Irradiation for Recurrent Cervical Cancer: A State-of-the-Art Review

The recurrence rate of cervical cancer after primary treatment can reach 60%, and a poor prognosis is reported in most cases. Treatment options for the recurrence of cervical cancer mainly depend on the prior treatment regimen and the location of recurrent lesions. Re-irradiation is still considered as a clinical challenge, owing to a high incidence of toxicity, especially in in-field recurrence within a short period of time. Recent advances in radiotherapy have preliminarily revealed encouraging outcomes of re-irradiation. Several centers have concentrasted on stereotactic body radiation therapy (SBRT) for the treatment of well-selected cases. Meanwhile, as the image-guiding techniques become more precise, a better dose profile can also be achieved in brachytherapy, including high-dose-rate interstitial brachytherapy (HDR-ISBT) and permanent radioactive seed implantation (PRSI). These treatment modalities have shown promising efficacy with a tolerable toxicity, providing further treatment options for recurrent cervical cancer. However, it is highly unlikely to draw a definite conclusion from all of those studies due to the large heterogeneity among them and the lack of large-scale prospective studies. This study mainly reviews and summarizes the progress of re-irradiation for recurrent cervical cancer in recent years, in order to provide potential treatment regimens for the management of re-irradiation.

Chinese Expert Consensus on Iodine125 Seed Implantation for Recurrent Cervical Cancer in 2021

The treatment modality for recurrent cervical cancer (rCC) is limited, and the prognosis of these patients is poor. Seed implantation could be an important component of rCC management in the context of dose boost or salvage therapy after surgery or radiotherapy, which is characterized by a minimally invasive, high local dose, and rapidly does fall, sparing normal tissue. For patients with good performance status and lateral pelvic wall recurrence with an available puncture path, seed implantation was recommended, as well as for selected central pelvic recurrence and extra-pelvic recurrence. The combination of brachytherapy treatment planning system and CT guidance was needed, and three-dimensional printing templates could greatly improve the accuracy, efficiency, and quality of seed implantation to achieve a potential ablative effect and provide an efficient treatment for rCC. However, the recommendations of seed implantation were mainly based on retrospective articles and lack high-quality evidence, and multicenter prospective randomized studies are needed. In this consensus on iodine¹²⁵ seed implantation for rCC, indication selection, technical process and requirements, dosimetry criteria, radiation protection, combined systemic therapy, and outcomes of seed implantation for rCC are discussed.

PD-1 Inhibitor Maintenance Therapy Combined Iodine-125 Seed Implantation Successfully Salvage Recurrent Cervical Cancer after CCRT: A Case Report

Cervical cancer is the fourth most common cancer in females worldwide. Patients with stage III and IV cervical cancer based on the Federation of Gynecology and Obstetrics (FIGO) classification have higher recurrence rates. Because of organs at risk (OAR) protection and the low indication rate of salvage surgery, the choice of treatment is always challenging. Systemic chemotherapy is palliative and can be performed in conjunction with surgery or radiotherapy; however, it has no significant benefit to survival. Brachytherapy and stereotactic body radiotherapy (SBRT) are characterized by extremely high radiation doses applied to tumor cells while sparing the normal tissues. Several studies have investigated the efficacy of these technologies in recurrent cervical cancer and showed promising results. The immune checkpoint inhibitors approach was also investigated and showed promising results too. Herein, we report a case of a patient with cervical cancer that recurred five months after adjuvant chemotherapy and concurrent chemoradiotherapy. The disease prognosis after interstitial implantation brachytherapy (IIB) was determined. Then, the patient underwent radioactive 125I-seed implantation combined with PD-1 inhibitor treatment. The patient exhibited a partial response after seed implantation, and up to now, the duration of this partial response was 24 months.