Preliminary application of 3D-printed coplanar template for iodine-125 seed implantation therapy in patients with advanced pancreatic cancer

Utilization of 3D printing technology in hepatopancreatobiliary surgery

The technology of three-dimensional (3D) printing emerged in the late 1970s and has since undergone considerable development to find numerous applications in mechanical engineering, industrial design, and biomedicine. In biomedical science, several studies have initially found that 3D printing technology can play an important role in the treatment of diseases in hepatopancreatobiliary surgery. For example, 3D printing technology has been applied to create detailed anatomical models of disease organs for preoperative personalized surgical strategies, surgical simulation, intraoperative navigation, medical training, and patient education. Moreover, cancer models have been created using 3D printing technology for the research and selection of chemotherapy drugs. With the aim to clarify the development and application of 3D printing technology in hepatopancreatobiliary surgery, we introduce seven common types of 3D printing technology and review the status of research and application of 3D printing technology in the field of hepatopancreatobiliary surgery.

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.

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.

3D printing in palliative medicine: systematic review

Background

Three-dimensional printing (3DP) enables the production of highly customised, cost-efficient devices in a relatively short time, which can be particularly valuable to clinicians treating patients with palliative care intent who are in need of timely and effective solutions in the management of their patients’ specific needs, including the relief of distressing symptoms.

Method

Four online databases were searched for articles published by December 2020 that described studies using 3DP in palliative care. The fields of application, and the relevant clinical and technological data were extracted and analysed.

Results

Thirty studies were reviewed, describing 36 medical devices, including anatomical models, endoluminal stents, navigation guides, obturators, epitheses, endoprostheses and others. Two-thirds of the studies were published after the year 2017. The main reason for using 3DP was the difficulty of producing customised devices with traditional methods. Eleven papers described proof-of-concept studies that did not involve human testing. For those devices that were tested on patients, favourable clinical outcomes were reported in general, and treatment with the use of 3DP was deemed superior to conventional clinical approaches. The most commonly employed 3DP technologies were fused filament fabrication with acrylonitrile butadiene styrene and stereolithography or material jetting with various types of photopolymer resin.

Conclusion

Recently, there has been a considerable increase in the application of 3DP to produce medical devices and bespoke solutions in the delivery of treatments with palliative care intent. 3DP was found successful in overcoming difficulties with conventional approaches and in treating medical conditions requiring highly customised solutions.

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.

Iodine-125 Seeds Inhibit Carcinogenesis of Hepatocellular Carcinoma Cells by Suppressing Epithelial-Mesenchymal Transition via TGF-β1/Smad Signaling

To investigate the radioactive iodine-125 (I-125) seed on migrating and invading of hepatocellular carcinoma (HCC) cells and its mechanism, the irradiation of PLC and Huh7 cells was carried out with I-125 seeds in vitro. Cell counting kit 8 assay was employed to measure cell viability. Cell migration was evaluated by using wound-healing assay. Cell invasion was detected by Transwell assay; RT-PCR and Western blot were used for the detection of the mRNA and proteins of TGF-β1 signaling pathway-related genes. The viability of PLC and Huh7 cells declined in a dose-dependent manner with increasing irradiation from 0 Gy, 2 Gy, 4 Gy, and 6 Gy, to 8 Gy, respectively. The IC50 of PLC and Huh7 cells were 6.20 Gy and 5.39 Gy, respectively, after 24 h of irradiation. Migration and invasion abilities of I-125 group cells were greatly weakened (P < 0.05) comparing with the control group. According to the outcomes of RT-PCR and WB, I-125 seed irradiation significantly inhibited the mRNA and protein expression of N-cadherin, vimentin, TGF-β1, p-Smad2/3, and Snail. But the mRNA and protein expressions of E-cadherin were enhanced. Rescue experiment demonstrates that TGF-β1 activator could reverse the inhibitory effects of I-125 on invasion and migration of cells. The results of in vivo experiments further verified that the I-125 seeds can inhibit the proliferation and TGF-β1 of xenographed PLC cells. In conclusion, I-125 seeds restrain the invasion and migration of HCC cells by suppressing epithelial to mesenchymal transition, which may associate with the inhibition of the TGF-β1 signaling.

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.

Evaluation of the efficacy of CT-guided 3D template-assisted 125I seed implantation in the treatment of unresectable STS: a multicenter retrospective study

To observe the safety and efficacy of CT-guided 3D template-assisted radioactive ¹²⁵I seed implantation in the treatment of unresectable advanced soft tissue sarcoma (STS). Sixty-two patients who underwent continuous 3D template-assisted radioactive ¹²⁵I seed implantation for the treatment of unresectable advanced STS from August 2017 to August 2018 were selected from four tumor treatment centers for retrospective analysis. The postoperative adverse reactions and tumor response were recorded, and the postoperative complications were observed and treated at the same time. The overall survival (OS) rate was determined. All patients successfully completed ¹²⁵I seed implantation. In practice, the median number of puncture needles used during the operation was 20, and the median number of ¹²⁵I particles was 88. There were no statistical differences in the relative dosimetry parameters before and after the operation (P > 0.05). Tumor evaluation was performed 6 months after the operation. The effective rate was 61.3%, and the local control rate was 93.5%. As of March 2020, the 1-year survival rate was 85.2%, and the 2-year survival rate was 49.0%. The OS was 23 months. CT-guided 3D template-assisted ¹²⁵I seed implantation for the treatment of unresectable STS has a high local control rate, thereby further prolonging the OS of patients with unresectable STS.

Three-Dimensional Printing of Medical Devices Used Directly to Treat Patients: A Systematic Review

Until recently, three-dimensional (3D) printing/additive manufacturing has not been used extensively to create medical devices intended for actual clinical use, primarily on patient safety and regulatory grounds. However, in recent years there have been advances in materials, printers, and experience, leading to increased clinical use. The aim of this study was to perform a structured systematic review of 3D-printed medical devices used directly in patient treatment. A search of 13 databases was performed to identify studies of 3D-printed medical devices, detailing fabrication technology and materials employed, clinical application, and clinical outcome. One hundred and ten papers describing one hundred and forty medical devices were identified and analyzed. A considerable increase was identified in the use of 3D printing to produce medical devices directly for clinical use in the past 3 years. This is dominated by printing of patient-specific implants and surgical guides for use in orthopedics and orthopedic oncology, but there is a trend of increased use across other clinical specialties. The prevailing material/3D-printing technology used were titanium alloy/electron beam melting for implants, and polyamide/selective laser sintering or polylactic acid/fused deposition modeling for surgical guides and instruments. A detailed analysis across medical applications by technology and materials is provided, as well as a commentary regarding regulatory aspects. In general, there is growing familiarity with, and acceptance of, 3D printing in clinical use.

Emerging technologies in brachytherapy

Brachytherapy is a mature treatment modality. The literature is abundant in terms of review articles and comprehensive books on the latest established as well as evolving clinical practices. The intent of this article is to part ways and look beyond the current state-of-the-art and review emerging technologies that are noteworthy and perhaps may drive the future innovations in the field. There are plenty of candidate topics that deserve a deeper look, of course, but with practical limits in this communicative platform, we explore four topics that perhaps is worthwhile to review in detail at this time. First, intensity modulated brachytherapy (IMBT) is reviewed. The IMBT takes advantage ofanisotropicradiation profile generated through intelligent high-density shielding designs incorporated onto sources and applicators such to achieve high quality plans. Second, emerging applications of 3D printing (i.e. additive manufacturing) in brachytherapy are reviewed. With the advent of 3D printing, interest in this technology in brachytherapy has been immense and translation swift due to their potential to tailor applicators and treatments customizable to each individual patient. This is followed by, in third, innovations in treatment planning concerning catheter placement and dwell times where new modelling approaches, solution algorithms, and technological advances are reviewed. And, fourth and lastly, applications of a new machine learning technique, called deep learning, which has the potential to improve and automate all aspects of brachytherapy workflow, are reviewed. We do not expect that all ideas and innovations reviewed in this article will ultimately reach clinic but, nonetheless, this review provides a decent glimpse of what is to come. It would be exciting to monitor as IMBT, 3D printing, novel optimization algorithms, and deep learning technologies evolve over time and translate into pilot testing and sensibly phased clinical trials, and ultimately make a difference for cancer patients. Today's fancy is tomorrow's reality. The future is bright for brachytherapy.

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.

Development of A 3D-Printed Navigational Template for Establishing Rabbit VX2 Lung Cancer Model

BACKGROUND

The CT-guided percutaneous puncture-inoculation for establishing the rabbit VX2 lung cancer model (LCM) is time-consuming, requires repeated CT scans, and has a high complication rate. Therefore, this study aimed to develop a navigational template using 3D technology to provide an alternative method for establishing the model with improved success and complication rates.

MATERIALS AND METHODS

Ideal pressure was determined using chest CT data from 15 anesthetized rabbits fitted with sphygmomanometer cuff around their chests. Subsequently, a preliminary 3D template with a square window and cross-sign to facilitate precise installation was designed. Using another 20 rabbits fixed with the preliminary template, an ideal common puncture point and parameter were determined, a navigational tunnel was set up on the template surface, and the final puncture navigational template was printed out. Eight-four rabbits (42/group) were assigned to the experimental (template-guided puncture) and control (traditional puncutre) groups and underwent VX2 tumor-fragment inoculation to validate the template. Differences in various parameters between two groups were analyzed.

RESULTS

The ideal pressure was 30 mmHg. All rabbits were inoculated successfully and the template adequately fit the rabbit chest. The experimental group displayed significantly better operation time (198.93±36.64 vs 735.14±91.19 seconds); number of CT scans (0 vs 7.19±1.64); pneumothorax (11.9% vs 35.7%), chest seeding (16.7% vs 35.7%), and mid-lung field tumor-bearing (88.1% vs 59.5%) rates than the control group (all, P <0.05). The groups did not differ in rib injury, tumor volume or survival time (all, P > 0.05).

CONCLUSIONS

We successfully developed a puncture navigational template, providing an alternative method for establishing the rabbit VX2 LCM.

Dosimetry study of three-dimensional print template for 125I implantation therapy

Background

¹²⁵I seed implantation has been found to show good therapeutic effects on tumors. Recent studies showed that three-dimensional (3D) print template-assisted ¹²⁵I seed implantation can optimize radiation dose distribution. This study aimed to compare the dose distribution differences in ¹²⁵I seed implantation among 3D print noncoplanar template- (3DPNCT), 3D print coplanar template- (3DPCT) assisted implantation and traditional free-hand implantation.

Methods

We systematically searched the PubMed, EMbase, Cochrane Library, Wan Fang Med Online, China National Knowledge Infrastructure (CNKI) from the earliest to November 2020 without time or language restrictions. And the references of primary literature were also searched. The outcome measures were dosimetry and operation time. This meta-analysis was carried out using Stata 12.0.

Results

A total of 16 original articles were selected for inclusion. The differences of D90, D100, V90, and V100 values pre- and post-implantation with traditional free-hand implantation showed statistically significant (p < 0.05). The differences of D90, D100, V100, V150, V200, and D2cc of organs at risk (OAR) values pre- and post-implantation with 3D print template showed no statistically significant (p > 0.05). Compared with traditional free-hand implantation without any templates, 3D print template could improve postoperative D90 (Standard mean difference, SMD = 0.67, 95% confidence interval (CI) = 0.35 to 0.98, p < 0.001), D100 (SMD = 0.82, 95%CI = 0.40 to 1.23, p < 0.001), V90 (SMD = 1.48, 95%CI = 0.95 to 2.00, p < 0.001), V100 (SMD = 1.41, 95%CI = 0.96 to 1.86, p < 0.001), and reduce operation time (SMD = − 0.93, 95%CI = − 1.34 to − 0.51, p < 0.001). In three studies, both 3DPNCT and 3DPCT plans were designed for all patients. The prescribed dose and seed activity were same. Pooled analysis of D90, D100, V100, D2cc of OAR, number of seeds and number of needles showed no significant differences between 3DPNCT and 3DPCT groups (p > 0.05). However, in 3DPNCT group, V150 and V200 were increased (SMD = 0.35, 0.49; 95%CI = 0.04 to 0.67, 0.02 to 0.96; p = 0.028, 0.043); the number of through bone needles was reduced (SMD = − 1.03, 95%CI = − 1.43 to − 0.64, p < 0.001).

Conclusions

Compared with traditional free-hand implantation, 3D print template-assisted ¹²⁵I seeds implantation can optimize dose distribution and reduce the implantation time at the same time. Compared with 3D print coplanar template, 3D print noncoplanar template can increase the volume of high dose within tumor target and is more safer in the respect of puncture route.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13014-021-01845-y.

A Retrospective Study on Using a Novel Single Needle Cone Puncture Approach for the Iodine-125 Seed Brachytherapy in Treating Patients With Thoracic Malignancy

Background

Patients with progressive thoracic malignancy characterized by large irregular tumors with necrosis and life-threatening symptoms lack effective treatments. We set out to develop a single needle cone puncture method for the Iodine-125 seed (SNCP-¹²⁵I) brachytherapy, and aim to report the initial results.

Methods

294 patients with advanced thoracic malignancy were treated with local SNCP-¹²⁵I brachytherapy between March 2009 and July 2020, followed by thorough evaluation of clinical outcome, overall survival (OS), progression-free survival (PFS) and procedure-related complications after treatment.

Results

The overall response rate (ORR) among the treated patients was 81.0% (238/294). Life-threatening symptoms due to tumor oppression, hemoptysis and large irregular tumor with necrosis were successfully alleviated after the SNCP-¹²⁵I treatment with a remission rate at 91% to 94%. The median OS and PFS were 13.6 months and 5.8 months, respectively. Procedure-related side effects including pneumothorax (32/294), blood-stained sputum (8/294), subcutaneous emphysema (10/294), puncture site bleeding (16/294) and chest pain (6/294) were observed. Patients who were able to follow with chemotherapy or immunotherapy experienced extended OS and PFS, as compared with patients who opted to receive hospice care (16.5 months Vs. 11.2 months). Further pathological and immunological analysis showed that SNCP-¹²⁵I induced tumor lymphocytes infiltration and long-term tumor necrosis.

Conclusion

SNCP-¹²⁵I brachytherapy effectively eliminates life-threatening symptoms due to local tumor oppression, hemoptysis and large irregular and necrotic tumors in patients with unresectable chest malignancy and significantly induces local tumor regression. SNCP-¹²⁵I brachytherapy combines with chemotherapy significantly prolong OS and PFS compare with SNCP-¹²⁵I brachytherapy alone.

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.

Manufacturing and evaluation of multi-channel cylinder applicator with 3D printing technology

Purpose

This study was designed to assess dosimetric characteristics of 3D-printed personalized multi-channel cylinder applicator (MCCA).

Material and methods

UnionTech RS Pro 600 (UnionTech, Inc., Shanghai, China) 3D printer was used for manufacturing MCCA. The geometry of MCCA was designed with Fusion 360 v.2.0.5827 (Autodesk, Inc.) software. The designed file was exported to Meshmixer v.3.5 (Autodesk, Inc.) to create three-dimensional model in stereolithography (STL) file format, which is the common file format for inputting data to 3D printers. We used high-temp resin, FLHTAM02 model (Formlabs Inc., MA, USA), as material in 3D printing process. This resin model has good resistance to high temperature and compatibility with various solvents. We created a simple cubic shape phantom for dosimetric evaluation of the applicator with Gafchromic EBT3 films. Also, Monte Carlo method was applied to simulate MCCA in the same configuration as in experimental test.

Results

The mean ± standard deviation (SD) difference between measured and calculated doses in treatment planning system (TPS) for all control points was 0.0860 ±0.0393 Gy, corresponding to 4.01 ±1.21%. The mean ±SD difference between doses calculated by Monte Carlo simulation and TPS for all control points was 0.0996 ±0.0471 Gy, corresponding to 4.58 ±1.05%. The mean ±SD of dose difference between film measurement and Monte Carlo simulation for all control points was 0.0136 ±0.0200 Gy, corresponding to 0.60 ±0.69%. P-value for dose difference between film measurement and TPS, Monte Carlo and TPS, and film measurement and Monte Carlo were 0.7, 0.66, and 0.95, respectively.

Conclusions

Dosimetric results and mechanical accuracy of MCCA show that high-temp resin with SLA 3D printing technique can be used for producing patient-specific MCCA in brachytherapy.

A novel combination of percutaneous stenting with iodine-125 seed implantation and chemotherapy for the treatment of pancreatic head cancer with obstructive jaundice

PURPOSE

Insertion of radioactive strips through the biliary stent has been reported to offer longer survival and patency than an uncovered conventional self-expanding metal stent in patients with unresectable malignant biliary obstruction. The aim of this study was to investigate the safety and effectiveness of intraluminal brachytherapy combined with ¹²⁵I seed implantation and transarterial infusion chemotherapy for the treatment of pancreatic head cancer with obstructive jaundice.

METHOD

From October 2012 to January 2018, 21 consecutive patients diagnosed with biliary obstruction caused by locally advanced, nonmetastatic pancreatic cancer with cytologically or histologically confirmed by biopsy were enrolled and receive treatment with intraluminal brachytherapy using ¹²⁵I seed strand and CT-guided percutaneous radioactive seed implantation therapy. The procedure-related and radiation complications were assessed. The outcomes were measured in terms of stent patency, patient survival, complications related to the procedure.

RESULT

One of the 22 patients (4.5%, 1/22) with pancreatic head cancer failed to perform the above procedure because the guidewire was unable to pass through the obstruction segment. The remaining 21 patients (95.5%, 21/22) with pancreatic head cancer with obstructive jaundice were successfully placed with biliary stents and radioactive strips through drainage tubes. The median number of ¹²⁵I seeds loaded was 15, ranging from 12 to 17. After the chemotherapy with gemcitabine and cisplatin, no adverse reaction of Grade Ⅲ ∼ Ⅳ occurred in all cases. Median stent patency was 12.50 months (95% CI: 10.26, 14.74). By May 2019, all 21 patients had died, with overall survival of 5.2-23.3 months, with a median survival of 13.20 months (95% CI: 10.96, 15.44).

CONCLUSION

Percutaneous ¹²⁵I seed implantation combined with insertion of radioactive strips through the biliary stent has the characteristics of less trauma, fewer complications, simple operation, and so on. These procedures bring remission of obstructive jaundice combined with the increased survival for the treatment of obstructive jaundice caused by unresectable pancreatic head cancer if follow-up chemotherapy is carried out. The long-term efficacy of this treatment combination needs to be confirmed by further multicenter, large sample size prospective randomized controlled studies.

Comparison of Image-Guided Iodine-125 Seed Interstitial Brachytherapy and Local Chemotherapy Perfusion in Treatment of Advanced Pancreatic Cancer

OBJECTIVE

To compare the efficacy and safety of iodine-125 seed interstitial brachytherapy and local chemotherapy perfusion in treatment of advanced pancreatic cancer.

METHODS

The present open prospective randomized control study included a total of 165 cases of advanced pancreatic cancer patients who were admitted in our hospital during December 2016 to April 2019. All patients were randomized into two groups with 84 cases in iodine-125 group and 81 cases in chemotherapy perfusion group. Basic clinical characteristics and demographic data were collected. The main outcome was the tumor efficiency. The pain condition was measured by visual analogue scale (VAS) and the Karnofsky score was also measured at different time points, before the treatment, 1 d, 7 d, 14 d, 1 mon, 2 mon and 3 mon after treatment. Serum levels of CEA, CA19-9 and CA50 were measured by immunochemiluminescence. The overall survival was analyzed by K-M curve.

RESULTS

The ratio of partial remission patients was significantly higher, and the ratio of stable disease (SD)+progressive disease patients was also remarkably lower in iodine-125 group than the chemotherapy perfusion group. The mean VAS scores decreased markedly after treatment and were significantly lower and the mean Karnofsky scores were remarkably higher in iodine-125 group than the chemotherapy perfusion group. The levels of CA19-9 and CA50 were remarkably lower in iodine-125 group, however no significant difference was found for CEA. The survival analysis by K-M curve showed the iodine-125 patients had longer overall survival time than the chemotherapy perfusion group. No infection, pancreatic fistula, biliary fistula, intestinal fistula, gastrointestinal obstruction or radiation enteritis was found in both groups.

CONCLUSION

Iodine-125 seed interstitial brachytherapy could achieve better efficacy with no increased side complications than chemotherapy perfusion in advanced pancreatic cancer.

Evaluation of radioactive 125I seed implantation for the treatment of refractory malignant tumours based on a CT-guided 3D template-assisted technique: efficacy and safety

Background

To observe the medium- and long-term clinical efficacy and safety of radioactive ¹²⁵I seed implantation for refractory malignant tumours based on CT-guided 3D template-assisted technique.

Methods

Twenty-five patients with refractory malignant tumours who underwent radioactive ¹²⁵I seed implantation based on CT-guided 3D template-assisted technique were selected. The post-operative adverse reactions were recorded. The number of puncture needles and particles used in the operation, dosimetric parameters, post-operative physical strength scores, and tumour response were statistically analysed. The overall survival time and survival rate were calculated, and the effect and prognosis were assessed.

Results

¹²⁵I seed implantation was successful in all patients without serious complications. The average number of implanted puncture needles was 17 (19.12 ± 13.00), and the median number of particles was 52 (55.12 ± 32.97). D₉₀ in the post-operative clinical target volume (CTV) (93.24 ± 15.70 Gy) was slightly lower than that in the pre-operative CTV (93.92 ± 17.60 Gy; P > 0.05). The D₉₀ in the post-operative planning target volume (PTV) (142.16 ± 22.25 Gy) was lower than the pre-operative PTV (145.32 ± 23.48 Gy; P > 0.05). The tumour responses at 6 months post-operatively: complete remission (CR), 20% (5/25); partial remission (PR), 48% (12/25); stable disease (SD), 24% (6/25); progressive disease (PD), 8% (2/25); CR + PR, 68% (17/25); and local control rate, 92% (23/25). The 6-, 12-, and 24-month survival rates were 100, 88, and 52%, respectively. The post-operative physical strength score (Karnofsky performance score, KPS) exhibited a gradual trend towards recovery, which rose to the highest value 12 months after implantation and then decreased slightly, but the average score was still > 90 points. There was one intra-operative pneumothorax, and two patients with superficial malignant tumours developed skin ulcerations. Multivariate analysis of prognosis showed that tumour sites and types were independent risk factors affecting survival. The number of needles and particles and template types were not the factors.

Conclusions

3D template combined with CT-guided radioactive ¹²⁵I seed implantation can improve the rational distribution of radiation dose in the tumour target area because accurate radioactive ¹²⁵I particle implantation was achieved. This technique has fewer complications and can further extend the overall survival and improve the quality of life.

Trial registration

Registration number: ChiCTR2000034566 2020/7/10 0:00:00

Retrospectively registered.