Tolerance of the aorta using intraoperative iodine-125 interstitial brachytherapy in cancer of the lung

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.

Irradiation stent insertion for inoperable malignant biliary obstruction: a meta-analysis of randomized controlled trials

The purpose of the study was to compare the relative clinical efficacies of irradiation stent (IRS) and conventional stent (CVS) insertions for the treatment of patients with malignant biliary obstruction (MBO). Pubmed, Embase, and Cochrane Library databases were searched for relevant randomized controlled trials (RCTs) from the date of inception through to August 2020. Data analysis was performed using RevMan v5.3. This meta-analysis included eight RCTs which included a total of 319 patients who had undergone IRS insertion, and 328 who had undergone CVS insertion. No significant differences in pooled Δ total bilirubin values (MD 0.34; P = 0.92), incident rates of cholangitis (P = 0.47), hemobilia (P = 0.60), or pancreatitis (P = 0.89) were detected between two groups. The rate of stent dysfunction was significantly lower in the IRS group compared to the CVS group (22.2% vs. 37.7%, P = 0.02). The pooled stent patency (P < 0.00001) and survival (P < 0.00001) were significantly longer in the IRS group compared to the CVS group. Significant heterogeneity was detected in the endpoints of rate of stent dysfunction (I² = 52%; P = 0.08) and survival (I² = 77%; P = 0.0005). Subgroup analysis was performed based on the different IRS types and showed significantly longer survival in the IRS group based on both types of IRS. Funnel plot analyses did not detect any evidence of publication bias. This meta-analysis included eight RCTs which included a total of 319 patients who had undergone IRS insertion, and 328 who had undergone CVS insertion. No significant differences in pooled Δ total bilirubin values (MD 0.34; P = 0.92), incident rates of cholangitis (P = 0.47), hemobilia (P = 0.60), or pancreatitis (P = 0.89) were detected between 2 groups. The rate of stent dysfunction was significantly lower in the IRS group compared to the CVS group (22.2% vs. 37.7%, P = 0.02). The pooled stent patency (P < 0.00001) and survival (P < 0.00001) were significantly longer in the IRS group compared to the CVS group. Significant heterogeneity was detected in the endpoints of rate of stent dysfunction (I² = 52%; P = 0.08) and survival (I² = 77%; P = 0.0005). Subgroup analysis was performed based on the different IRS types and showed significantly longer survival in the IRS group based on both types of IRS. Funnel plot analyses did not detect any evidence of publication bias. Our meta-analysis demonstrates that IRS insertion can prolong stent patency and the survival of patients with MBO compared to CVS insertion.

Brachytherapy for lung cancer

Brachytherapy (BT) is a minimally invasive anticancer radiotherapeutic modality where the tumor is directly irradiated via a radioactive source that is precisely implanted in or adjacent to the tumor. BT for lung cancer may be conducted in the form of endobronchial BT and radioactive seed implantation (RSI-BT), mainly for nonsmall cell lung cancer (NSCLC). For patients with early-stage lung cancer who are not suitable for surgery or external beam radiotherapy (EBRT), BT may be used as an alternative treatment, and curative results could be achieved in certain patients with cancer confined to the trachea lumen. For patients with locally advanced/metastatic lung cancer, BT could be selectively applied alone or as a boost to EBRT, which could improve the local tumor control and patient's survival. In addition, BT is also useful as a salvage treatment in select patients with locally recurrent/residual lung cancer that failed other treatments (e.g., surgery, chemotherapy, and EBRT). However, clinical outcomes are mainly obtained from retrospective studies. Prospective studies are limited and needed. In recent years, the introduction of modern image guidance, novel radioactive seeds, BT treatment planning systems (BT-TPS), after-loading technique, and three-dimensional printing template (3D-PT) assistance, among others, have potentially improved the clinical outcomes of BT. However, a comprehensive review of BT with newly published literature was lacking. This review is to discuss BT for NSCLC based on recent literature published in PubMed.

Clinical Research on Systemic Chemotherapy Combined With Bronchoscopic Seed Implantation in the Treatment of Advanced Lung Cancer

Objective:

This study aims to explore the clinical value of systemic chemotherapy combined with bronchoscopic seed implantation in advanced lung cancer treatment.

Methods:

The study enrolled 253 patients with advanced lung cancer in Cangzhou People’s Hospital from March 2018 to March 2020, and they were divided into test group and control group. Test group was given systemic chemotherapy combined with bronchoscopic seed implantation, while control group was given systemic chemotherapy. The objective response rate of tumor (ORR), disease control rate (DCR), serum tumor marker level, survival time and adverse reactions of 2 groups were compared.

Results:

After treatment, the levels of serum tumor markers including carcino-embryonic antigen, neuro-specific enolase, cytokeratin-19 and pro-gastrin-releasing peptide were markedly decreased in test group compared with those in control group (P < 0.05). Therein, the serum tumor marker level of non-small cell lung cancer (NSCLC) patients was significant decreased compared with that of small cell lung cancer (SCLC) patients in test group. Meanwhile, in test group, the serum tumor marker level of lung adenocarcinoma (LUAD) patients was significant decreased compared with that of lung squamous cell carcinoma (LUSC, P < 0.05). The ORR and DCR in test group were superior to those in control group (63.4%, 92.5% vs 38.7%, 72.3%, P < 0.05), while those were much higher in patients with NSCLC and LUAD relative to those in patients with SCLC and LUSC, respectively (P < 0.05). Furthermore, the progression-free survival (PFS) and overall survival (OS) in test group were significantly greater than those in control group. In test group, the PFS and OS of patients with NSCLC and LUAD were higher than those of patients with SCLC and LUSC.

Conclusion:

The efficacy of systemic chemotherapy combined with bronchoscopic seed implantation was superior to that of systemic chemotherapy, which is worthy of promoting in clinical practice.

Ultrasound-Guided 125I Seed Implantation in Treatment of Abdominal Wall Metastases

Background: The treatment of abdominal wall metastasis presents a challenge, because resection can be followed by poor healing and external radiotherapy is associated with serious adverse events. This study aimed to evaluate the efficacy and safety of interstitial ¹²⁵I seed implantation under ultrasound (US) guidance for treating abdominal wall metastasis. Materials and Methods: The cases of 21 patients with 28 abdominal wall metastases who received brachytherapy with ¹²⁵I seeds at the department from August 2010 to March 2015 were retrospectively reviewed. ¹²⁵I seeds were implanted in the abdominal wall lesions under US guidance and with the help of a treatment planning system. Follow-up was performed using computed tomography at 1 d and at 3, 6, and 12 months after implantation. The lymphocyte count before the surgery was compared with the 3-month postoperative count. The main indicators observed were changes in tumor size, side effects, and complications. Results: All 21 patients were successfully treated with ¹²⁵I seed implantation under US guidance. The median follow-up since ¹²⁵I seed implantation was 15 months (range 6-23 months). The response rates and local tumor control after 3, 6, and 12 months were 78.6% and 89.3%, 64.3% and 85.7%, and 52.4% and 71.4%, respectively. The mean preoperative lymphocyte count was 0.262 ± 0.117 × 10⁹/L, which did not differ significantly from the postoperative count, which was 0.259 ± 0.094 × 10⁹/L (p = 0.122). Procedure-related complications included fever, bleeding, and pain, but all these were Grade 1-2. No severe side effects or complications were noted. Conclusions: Percutaneous interstitial implantation of ¹²⁵I seeds under US guidance is safe and feasible for abdominal wall metastases. However, its long-term efficacy requires further investigation.

Current status of brachytherapy in cancer treatment - short overview

Cancer incidence and mortality depend on a number of factors, including age, socio-economic status and geographical location, and its prevalence is growing around the world. Most of cancer treatments include external beam radiotherapy or brachytherapy. Brachytherapy, a type of radiotherapy with energy from radionuclides inserted directly into the tumor, is increasingly used in cancer treatment. For cervical and skin cancers, it has become a standard therapy for more than 100 years as well as an important part of the treatment guidelines for other malignancies, including head and neck, skin, breast, and prostate cancers. Compared to external beam radiotherapy, brachytherapy has the potential to deliver an ablative radiation dose over a short period of time directly to the altered tissue area with the advantage of a rapid fall-off in dose, and consequently, sparing of adjacent organs. As a result, the patient is able to complete the treatment earlier, and the risks of occurrence of another cancer are lower than in conventional radiotherapy treatment. Brachytherapy has increased its use as a radical or palliative treatment, and become more advanced with the spread of pulsed-dose-rate and high-dose-rate afterloading machines; the use of new 3D/4D planning systems has additionally improved the quality of the treatment. The aim of the present study was to present short summaries of current studies on brachytherapy for the most frequently diagnosed tumors. Data presented in this manuscript should help especially young physicians or physicists to explore and introduce brachytherapy in cancer treatments.

Effectiveness of 125I seed implantation in the treatment of non-small cell lung cancer during R2 resection

The aim of the present study was to investigate the effectiveness of ¹²⁵I particle implantation during R2resection for non-small cell lung cancer (NSCLC). Data from 23 patients with NSCLC and macroscopic residual diseasefollowing surgery (R2 resection) between March 2010 and May 2014 were retrospectively analyzed. Among these patients, 12 patients [4 with T-residual disease (incomplete resection of primary tumor but complete dissection of regional lymph node), 8 with N-residual disease (complete resection of primary tumor but incomplete resection of metastatic regional lymph node)] underwent ¹²⁵I particle implantation during the operation, while the other 11 (4 with T-residual disease and 7 with N-residual disease) received postoperative conventional radiotherapy. The local control rate, overall survival, and distant metastasis were evaluated. Additionally, the efficacy and safety of brachytherapy using ¹²⁵I particle implantation during surgery for locally advanced NSCLC were investigated. The 23 patients were followed up for 3–40 months. For the ¹²⁵I group, the 2-year local control rate was 100%, and the median survival time was 24 months. The 1–2-year survival rates were 83.3 and 58.33%, respectively. For the postoperative radiotherapy group, the median survival time was 12 months, andthe 1- and 2-year survival rates were 54.5 and 27.7%, respectively. No statistically significant difference in 2-year survival rates was detected between the two treatment groups, but the particle implantation group exhibited a higher survival rate trend. For patients with T-residual disease, the survival rate was higher for the ¹²⁵I seed implantation group compared with the postoperative radiotherapy group. However, there was no significant difference in the rates of metastasis between the two groups for patients with N-residual disease. Therefore, intraoperative implantation of ¹²⁵I particles during R2 resection of NSCLC may be a safer and more reliable method to reduce the local recurrence rate compared with conventional radiotherapy. Although not statistically significant, the overall survival rate of patients in the ¹²⁵I seed implantation group was higher compared with the postoperative radiotherapy group.

CT-guided 125I brachytherapy for recurrent ovarian cancer

This retrospective study was to evaluate the local control and survival of ¹²⁵I brachytherapy for recurrent ovarian cancer. 52 ¹²⁵I brachytherapy procedures were performed in 47 patients with 51 recurrent ovarian cancer lesions. The follow-up period was 1-55 months (median 12 months). The local control rate (LC) of 3, 6, 12, 24 and 36 months was 93.3%, 77.7%, 58.9%, 38.7% and 19.3%, respectively. Patients with tumor size ≤ 4cm (85.7% vs 40.0%, P = 0.037) and actual D90 between 110 to 130Gy (47.4% vs 66.7% vs 62.5%, P = 0.029) had better LC. The 1, 2 and 3 years of overall survival (OS) was 79.3%, 63.0% and 52.5%, respectively. The poor performance status (HR 3.821, 95% CI 1.383-10.555; P = 0.010), concurrent distant metastasis (HR 9.222, 95% CI 1.710-49.737; P = 0.010) and large postoperative residual tumor size (HR 6.157, 95% CI 1.438-26.367; P = 0.014) were closely correlated with a poor OS. Our data indicate thatCT-guided ¹²⁵I brachytherapy is an effective and safe modality for the local treatment of recurrent ovarian cancer.

Treating cancerous large airway stenosis with staging radioactive particle implantation guided by computed tomography and fiber bronchoscopy: a clinical study

Background

The purpose of this study is to investigate the clinical effectiveness of staging radioactive particle implantation guided by computed tomography (CT) and fiber–optic bronchoscopy in treating cancerous large airway stenosis.

Methods

A total of 102 patients were included; 57 had undergone staging radioactive particle implantation guided by CT and fiber bronchoscopy and 45 did not. Patients were evaluated by CT and fiber–optic bronchoscopy to determine the feasibility of the implantation of radioactive seeds for the treatment of cancerous large airway stenosis. The treatment planning system (TPS) was used to plan the doses. Radioactive seeds were implanted using fiber–optic bronchoscopy. One week later, CT-guided implantation of radioactive seeds was performed.

Results

The clinical evaluation showed complete, partial, slight, and non-response in 38, 14, 5, and 0 patients, respectively. None of the patients were found with serious complications. The diameter of the affected airway, Karnofsky score, dyspnea index, survival, and quality of life of the patients in both groups was significantly higher and significantly different after the treatment (P < 0.05). The dyspnea index was significantly lower in the treatment group as compared with the control group (P < 0.001).

Conclusion

CT- and fiber bronchoscopy-guided staging radioactive particle implantation has definite treatment effectiveness in treating cancerous large airway stenosis. It should be widely used in clinical practices.

Novel Silicone-Coated 125I Seeds for the Treatment of Extrahepatic Cholangiocarcinoma

125I seeds coated with titanium are considered a safe and effective interstitial brachytherapy for tumors, while the cost of 125I seeds is a major problem for the patients implanting lots of seeds. The aim of this paper was to develop a novel silicone coating for 125I seeds with a lower cost. In order to show the radionuclide utilization ratio, the silicone was coated onto the seeds using the electro-spinning method and the radioactivity was evaluated, then the anti-tumor efficacy of silicone 125I seeds was compared with titanium 125I seeds. The seeds were divided into four groups: A (control), B (pure silicone), C (silicone 125I), D (titanium 125I) at 2 Gy or 4 Gy. Their anti-tumour activity and mechanism were assessed in vitro and in vivo using a human extrahepatic cholangiocarcinoma cell line FRH-0201 and tumor-bearing BALB/c nude mice. The silicone 125I seeds showed higher radioactivity; the rate of cell apoptosis in vitro and the histopathology in vivo demonstrated that the silicone 125I seeds shared similar anti-tumor efficacy with the titanium 125I seeds for the treatment of extrahepatic cholangiocarcinoma, while they have a much lower cost.

American Brachytherapy Society consensus guidelines for thoracic brachytherapy for lung cancer

PURPOSE

To update brachytherapy recommendations for pretreatment evaluation, treatment, and dosimetric issues for thoracic brachytherapy for lung cancer.

METHODS AND MATERIALS

Members of the American Brachytherapy Society with expertise in thoracic brachytherapy updated recommendations for thoracic brachytherapy based on literature review and clinical experience.

RESULTS

The American Brachytherapy Society consensus guidelines recommend the use of endobronchial brachytherapy for disease palliation in patients with central obstructing lesions, particularly in patients who have previously received external beam radiotherapy. The use of interstitial implants after incomplete resection may improve outcomes and provide enhanced palliation. Early reports support the use of CT-guided intratumoral volume implants within clinical studies. The use of brachytherapy routinely after sublobar resection is not generally recommended, unless within the confines of a clinical trial or a registry.

CONCLUSIONS

American Brachytherapy Society recommendations for thoracic brachytherapy are provided. Practitioners are encouraged to follow these guidelines and to develop further clinical trials to examine this treatment modality to increase the evidence base for its use.

Brachytherapy in the treatment of lung cancer - a valuable solution

The majority of patients with lung cancer are diagnosed with clinically advanced disease. Many of these patients have a short life expectancy and are treated with palliative aim. Because of uncontrolled local or recurrent disease, patients may have significant symptoms such as: cough, dyspnea, hemoptysis, obstructive pneumonia, or atelectasis. Brachytherapy is one of the most efficient methods in overcoming difficulties in breathing that is caused by endobronchial obstruction in palliative treatment of bronchus cancer. Efforts to relieve this obstructive process are worthwhile, because patients may experience improved quality of their life (QoL). Brachytherapy plays a limited but specific role in definitive treatment with curative intent in selected cases of early endobronchial disease as well as in the postoperative treatment of small residual peribronchial disease. Depending on the location of the lesion, in some cases brachytherapy is a treatment of choice. This option is fast, inexpensive, and easy to perform on an outpatient basis. Clinical indications, different techniques, results, and complications are presented in this work.

Computed Tomography-Guided Interstitial High-Dose-Rate Brachytherapy in Combination With Regional Positive Lymph Node Intensity-Modulated Radiation Therapy in Locally Advanced Peripheral Non-Small Cell Lung Cancer: A Phase 1 Clinical Trial

PURPOSE

To assess the technical safety, adverse events, and efficacy of computed tomography (CT)-guided interstitial high-dose-rate (HDR) brachytherapy in combination with regional positive lymph node intensity modulated radiation therapy in patients with locally advanced peripheral non-small cell lung cancer (NSCLC).

METHODS AND MATERIALS

Twenty-six patients with histologically confirmed NSCLC were enrolled in a prospective, officially approved phase 1 trial. Primary tumors were treated with HDR brachytherapy. A single 30-Gy dose was delivered to the 90% isodose line of the gross lung tumor volume. A total dose of at least 70 Gy was administered to the 95% isodose line of the planning target volume of malignant lymph nodes using 6-MV X-rays. The patients received concurrent or sequential chemotherapy. We assessed treatment efficacy, adverse events, and radiation toxicity.

RESULTS

The median follow-up time was 28 months (range, 7-44 months). There were 3 cases of mild pneumothorax but no cases of hemothorax, dyspnea, or pyothorax after the procedure. Grade 3 or 4 acute hematologic toxicity was observed in 5 patients. During follow-up, mild fibrosis around the puncture point was observed on the CT scans of 2 patients, but both patients were asymptomatic. The overall response rates (complete and partial) for the primary mass and positive lymph nodes were 100% and 92.3%, respectively. The 1-year and 2-year overall survival (OS) rates were 90.9% and 67%, respectively, with a median OS of 22.5 months.

CONCLUSION

Our findings suggest that HDR brachytherapy is safe and feasible for peripheral locally advanced NSCLC, justifying a phase 2 clinical trial.

Efficacy of permanent iodine-125 seed implants and gemcitabine chemotherapy in patients with platinum- resistant recurrent ovarian carcinoma

BACKGROUND

The aim of this study was to explore the efficacy and adverse reactions of CT-guided radioactive 125I-seed implantation treatment combined with chemotherapy for platinum-resistant recurrent ovarian carcinoma.

MATERIALS AND METHODS

From September 2010 to December 2012, 23 patients with platinum-resistant recurrent ovarian carcinoma were enrolled. All the patients refused, could not bear, or were not suitable for surgery. They all had no more than 3 lesions, which were detected and could also be measured by CT. All were clarified as single-lesion or multiple-lesion groups. A total of 41 lesions underwent implantation of from 8 to 106 125I seeds (median=43). Multi-plane implanting was adopted and 125I-seeds of (0.4-0.7)mCi were placed at intervals of (0.5-1.0) cm. After implantation treatment, all patients underwent 4 cycles of chemotherapy with gemcitabine 800 mg/m2 (days 1, 8 and 15).

RESULTS

The outcome was evaluated with CT 3 weeks and every 3 months after implantation treatment. After 6 months, the volume of 32 out of 41 lesions (78.0%) was reduced at least 30%, within which 9 lesions completely disappeared(22.0%). Complete response was observed in 7 cases (30.4%), with a partial response in 4 cases (17.4%),4 cases stable(17.4%)and 8 cases showing progression (34.8%). The total clinical remission rate was 47.8% (11/23). The clinical remission rate was 77.8% (7/9) in the single-lesion group and 28.6% (4/14) in the multiple-lesion group with a significant difference between the two(P=0.036). The common side effects observed were mild gastrointestinal reactions.

CONCLUSIONS

125I-seed implantation combined with chemotherapy applies an effective way in the treatment of platinum-resistant recurrent ovarian epithelial carcinoma with the advantages of high local control rates, good short-term effects, little trauma and less side effects.

Recurrent primary lumbar vertebra chondrosarcoma: Marginal resection and Iodine-125 seed therapy

Chondrosarcomas are uncommon in the spinal column. En bloc excisions with wide margins are of critical importance but not always feasible in spine. We report the outcome in a case of recurrent lumbar vertebral chondrosarcoma treated with marginal resection and iodine-125 seeds placed in the resected tumor bed.

Monte Carlo calculated doses to treatment volumes and organs at risk for permanent implant lung brachytherapy

Iodine-125 ((125)I) and Caesium-131 ((131)Cs) brachytherapy have been used with sublobar resection to treat stage I non-small cell lung cancer and other radionuclides, (169)Yb and (103)Pd, are considered for these treatments. This work investigates the dosimetry of permanent implant lung brachytherapy for a range of source energies and various implant sites in the lung. Monte Carlo calculated doses are calculated in a patient CT-derived computational phantom using the EGsnrc user-code BrachyDose. Calculations are performed for (103)Pd, (125)I, (131)Cs seeds and 50 and 100 keV point sources for 17 implant positions. Doses to treatment volumes, ipsilateral lung, aorta, and heart are determined and compared to those determined using the TG-43 approach. Considerable variation with source energy and differences between model-based and TG-43 doses are found for both treatment volumes and organs. Doses to the heart and aorta generally increase with increasing source energy. TG-43 underestimates the dose to the heart and aorta for all implants except those nearest to these organs where the dose is overestimated. Results suggest that model-based dose calculations are crucial for selecting prescription doses, comparing clinical endpoints, and studying radiobiological effects for permanent implant lung brachytherapy.

Efficacy and safety of percutaneous microwave coagulation therapy followed by 125I seed brachytherapy for VX2 hepatic tumors in a rabbit model

The aim of this study was to evaluate the efficacy and safety of percutaneous microwave coagulation therapy (PMCT) followed by ¹²⁵I seed brachytherapy for VX2 liver cancer in rabbits. Eighty New Zealand rabbits were injected with suspensions of VX2 tumor cells to create an animal model. The rabbits were randomly divided into 4 groups (n=20); the control, PMCT, ¹²⁵I seed brachytherapy and combination groups. Group A was treated with PMCT at 40 W for 120 sec, group B was treated with ¹²⁵I seed brachytherapy and group C was treated with PMCT followed by ¹²⁵I seed brachytherapy. Group D were not treated and served as the control group. At 21 days after treatment, the rabbits were sacrificed for pathological assessment. The complete tumor necrosis rate was 19 out of 20 tumors (95%) in group C, 6 (30%) in group A, 0 (0%) in group B and 0 (0%) in the control group. The complete tumor necrosis rate was observed to be significantly different between groups C and A, and between groups C and B (P<0.01). No intraheptic metastasis occurred in group C, compared with an incidence of 7 (35%) in group A, 2 (10%) in group B and 20 (100%) in the control group. Between groups C and A, and between groups C and D, the intraheptic metastasis rate was statistically significant (P<0.01). PMCT followed by ¹²⁵I seed brachytherapy increased the rate of carcinoma necrosis and decreased carcinoma metastasis in the VX2 rabbit model. This combined treatment is a safe, effective and minimally invasive therapeutic option for liver cancer.

Combination of cryosurgery and Iodine-125 seeds brachytherapy for lung cancer

It has been proven that radioactive seeds such as Iodine-125 seeds implantation is a highly effective treatment for patients with localized cancer, such as lung cancer. It may increase the effectiveness of cryosurgery for lung cancer with the combination of Iodine-125 seed implantation into edge of the cryoablation zone. Percutaneous cryosurgery and Iodine-125 seed implantation are mutual complementation; both have been proved to be safe and effective modality for unresectable lung cancer, especially for centrally located lung cancer. Well-designed, randomized and control study both in the laboratory and in the clinical about this option are needed before the conclusive evidence submits.

Damage to pig bile duct caused by intraluminal brachytherapy using a (125)I ribbon

BACKGROUND

Stent occlusion by tumor ingrowth or overgrowth is the main cause of jaundice recurrence after metal stent insertion in patients with malignant obstructive jaundice (MOJ). The application of intraluminal brachytherapy (ILBT) in patients with MOJ results in local control of malignant tumors, which prolong stent patency.

PURPOSE

To evaluate the safety of ILBT in pig bile ducts using ribbons of iodine-125 ((125)I) seeds.

MATERIAL AND METHODS

Sixteen healthy pigs were randomly assigned to four groups of four pigs each. A (125)I seed ribbon was implanted into the common bile duct of each animal through an incision in the duct wall, and was fixed by suturing. The four groups of animals were sacrificed at 15, 30, 60, and 120 days after ribbon implantation, respectively. Serum bilirubin concentrations, alanine aminotransferase concentrations, and white blood cell counts before and after implantation were compared within each group. Pathological changes to the bile duct wall were observed using a light microscope. Morphological changes in biliary epithelial cells and organelles were observed with electron microscopy.

RESULTS

(125)I ribbons were successfully implanted in all animals without surgery-related death. We found no significant difference in pre- and post-implant serum bilirubin, alanine aminotransferase, or white blood cell counts. Light and electron microscopy showed that the most severe bile duct damage occurred in the 15-day group, which exhibited necrosis and detachment of numerous epithelial cells, and infiltration of inflammatory cells. Repair and proliferation of the bile duct epithelium began 30 days after implantation and was nearly complete at 60 days.

CONCLUSION

This study demonstrated the safety of ILBT using a (125)I ribbon in the pig bile duct. (125)I seed ribbons may be used in the treatment of MOJ in humans.

Aortic dose constraints when reirradiating thoracic tumors

BACKGROUND AND PURPOSE

Improved radiation delivery and planning has allowed, in some instances, for the retreatment of thoracic tumors. We investigated the dose limits of the aorta wherein grade 5 aortic toxicity was observed after reirradiation of lung tumors.

MATERIAL AND METHODS

In a retrospective analysis, 35 patients were identified, between 1993 and 2008, who received two rounds of external beam irradiation that included the aorta in the radiation fields of both the initial and retreatment plans. We determined the maximum cumulative dose to 1 cm(3) of the aorta (the composite dose) for each patient, normalized these doses to 1.8 Gy/fraction, and corrected them for long-term tissue recovery between treatments (NIDR).

RESULTS

The median time interval between treatments was 30 months (range, 1-185 months). The median follow-up of patients alive at analysis was 42 months (range, 14-70 months). Two of the 35 patients (6%) were identified as having grade 5 aortic toxicities. There was a 25% rate of grade 5 aortic toxicity for patients receiving composite doses ≥120.0 Gy (vs. 0% for patients receiving <120.0 Gy) (P=0.047).

CONCLUSIONS

Grade 5 aortic toxicities were observed with composite doses ≥120.0 Gy (NIDR ≥90.0 Gy) to 1cm(3) of the aorta.

Management of single malignant lung nodules in elderly patients (70 years or older) who are not candidates for lobectomy

PURPOSE

The aim of this study was to evaluate and compare sublobar resection plus intraoperative seed implant (IOS) versus stereotactic body radiation therapy (SBRT) in patients with single malignant lung nodules in patients 70 years of age or older.

MATERIALS AND METHODS

A retrospective chart review was performed and 47 patients with adequate information were selected for analysis. Thirty patients with single malignant lung nodules received SBRT. Seventeen patients received limited surgical resection plus radioactive seed implantation for solitary malignant lung nodules. Univariate statistical analysis showed a significant difference only for the age in the 2 groups: the mean age in the radioactive seed group, 78.8 years versus 76.1 years in the SBRT group (2-sided, P=0.05).

RESULTS

There was high local control and minimal toxicity with either treatment modality and no significant difference among the 2 groups in terms of local control, survival, and toxicity. However, the distant failure was higher but not statistically significant in the SBRT group (9 of 30 patients in SBRT vs. 0 of 17 in IOS, P=0.1).

CONCLUSIONS

Our study has shown excellent outcomes and limited toxicity in both IOS and SBRT for treatment of single malignant lung nodules in patients who are not candidates for lobectomy. However, a randomized trial is needed in this group of elderly patients to determine the most appropriate treatment.

Novel use of endoluminal repair as prophylaxis of aortic rupture secondary to radiotherapy for lung cancer

Non-small-cell lung cancer (NSCLC) invading the aorta is staged as T(4). Only 9% of T(4) tumors are resected; the alternative is chemoradiotherapy, but for peri-aortic NSCLC, radiation damage to the aortic wall can induce fatal rupture. We report the case of a 76 year-old man with a 3-cm left lower lobe NSCLC clearly invading the aortic wall. A thoracic stent graft was inserted prophylactically to prevent aortic rupture. He then received 64 Gy radiotherapy in 32 fractions, resulting in tumor shrinkage. Prophylactic aortic endografting, a less invasive treatment than open surgery, may enable high dose irradiation of the aortic wall.

Clinical application of CT-guided (125)I seed interstitial implantation for local recurrent rectal carcinoma

PURPOSE

The present study aimed to explore the safety profile and clinical efficacy of CT-guided radioactive seed implantation in treating local recurrent rectal carcinoma.

MATERIALS AND METHODS

CT-guided ¹²⁵I seed implantation was carried out in 20 patients with locally recurrent rectal carcinoma. 14 of the 20 patient had prior adjuvant external-beam radiation therapy (EBRT). The treatment planning system (TPS) was used preoperatively to reconstruct three dimensional images of the tumor and to calculate the estimated seed number and distribution. The median matched peripheral dose (MPD) was 120 Gy (range, 100-160 Gy).

RESULTS

Of the 20 patients, 12 were male, 8 were female, and ages ranged from 38 to 78, with a median age of 62. Duration of follow-up was 3-34 months. The response rate of pain relief was 85% (17/20). Repeat CT scan 2 months following the procedure revealed complete response (CR) of the tumor in 2 patients, partial response (PR) in 13 patients, stable disease (SD) in 3 patients, and progressive disease (PD) in 2 patients. 75% of patients had either CR or PR. Median survival time was 18.8 months (95% CI: 3.5-22.4 months). 1 and 2 year survival rates were 75% and 25%, respectively. 4 patients died of recurrent tumor; 4 patients died of distant metastases; 9 patients died of recurrent tumor and distant metastases. 3 patients survived after 2 year follow up. Two patients were found to have mild hematochezia, which was reversible with symptomatic management.

CONCLUSION

CT-guided ¹²⁵I seed implantation appeared to be a safe, useful and less complicated interventional treatment option for local recurrent rectal carcinoma.

The combined treatment of CT-guided percutaneous 125I seed implantation and chemotherapy for non-small-cell lung cancer

PURPOSE

Gemcitabine plus cisplatin (GP) is a first-line treatment for advanced non-small-cell lung cancer (NSCLC). In this study, we evaluated the efficacy and safety of a combined treatment consisting of CT-guided percutaneous (125)I seed implantation with GP chemotherapy for advanced NSCLC.

METHODS

Fifty-three patients with advanced NSCLC were enrolled in a nonrandomized, two-armed clinical trial. Of these patients, 24 received a combination treatment of CT-guided percutaneous (125) I seed implantation and GP (the combo group), while 29 were treated with GP only (the control group).

RESULTS

Patients in the combo group received (125)I seed implantation with prescription dose of 100-140 Gy and a total of 55 cycles of GP, and patients in the control group received a total of 73 cycles of GP. The overall response rate was 79.2% in the combo group and 41.4% in the control group. The median overall survival time was 13.5 ± 1.5 months in the combo group and 9.0 ± 1.8 months in the control group. The progression-free survival time was 8.0 ± 1.2 months in the combo group and 5.0 ± 0.8 months in the control group. The 1- and 2-year survival rates were 62.5 and 16.7% in the combo group, respectively, and 41.4 and 13.8% in the control group. The interventional complications in the combo group included 5 cases of pneumothorax and 4 cases of hemoptysis. There were no complications due to radiation pneumonia or radiation esophagitis in the combo group, and no patients had lethal hemoptysis or esophagotracheal fistula. Chemotherapy treatment-related toxicities, including Grade 3/4 myelosuppression and Grade 3 gastrointestinal toxicity, were similar in both groups.

CONCLUSIONS

Our initial experience showed that combined CT-guided (125)I radioactive seed implantation and GP chemotherapy are effective and safe for treating advanced NCSLC.

The use of ¹²⁵I seed strands for intraluminal brachytherapy of malignant obstructive jaundice

This study is sought to evaluate the feasibility and safety of using ¹²⁵I seed strands for intraluminal brachytherapy (ILBT) in the treatment of malignant obstructive jaundice (MOJ), and its clinical effect on stent patency. A total of 34 patients found to have MOJ were randomly assigned to an ILBT treatment group or a control group before biliary stent insertion. For the ILBT group, ¹²⁵I seed strands were implanted into the obstructive segment of the bile duct after stent insertion. For the control group, only the biliary stent was inserted. Alimentary and hematologic complications were examined for patients in the ILBT group. The stent patency of the two groups were compared. In the ILBT group, the number of ¹²⁵I seeds per strand varied from 6 to 16 (mean, 10.9), and were successfully implanted in 17 patients. Serum levels of bilirubin, alanine aminotransferase, granulocytes, and platelets assayed 2 and 4 weeks following the procedure demonstrated no significant difference between the ILBT group and the control group. The mean stent patency for ILBT group (10.2 months) was significantly longer than that of the control group (7.2 months, p=0.032). ¹²⁵I seed strands for ILBT is a feasible and safe palliative therapy for the treatment of MOJ, and may prolong stent patency.

Cesium-131 permanent seed brachytherapy: dosimetric evaluation and radiation exposure to surgeons, radiation oncologists, and staff

PURPOSE

Cesium-131 ((131)Cs) radioactive seed is Food and Drug Administration approved for permanent seed implant for all cancers, including lung and head and neck (HN) cancers. We describe the first clinical report of (131)Cs dosimetry and exposure rates to treating physicians and staff.

METHODS AND MATERIALS

Twenty-eight patients received (131)Cs implant for early stage lung and recurrent HN cancers. A nomogram was developed to calculate the number of seeds needed to cover the wedge line with the prescription dose (80 Gy). Final dosimetry was obtained after CT planning a few days following the surgical procedure. Radiation exposure to the treating physicians and staff was measured at the completion of the procedure.

RESULTS

A nomogram was developed using the variseed software with source data from American Association of Physicists in Medicine TG-43 report. The total volume covered by the prescription isodose line of (131)Cs was measured and compared with (125)I. The prescription volume was smaller for (131)Cs. In addition, the exposure rate with (131)Cs was found to be acceptable.

CONCLUSION

Our preliminary experience with (131)Cs lung and HN brachytherapy has been very encouraging with excellent dosimetric coverage and acceptable exposure to the treating physicians and staff.

Clinical efficacy of CT-guided iodine-125 seed implantation therapy in patients with advanced pancreatic cancer

OBJECTIVE

To examine the clinical efficacy of CT-guided radioactive iodine-125 (125I) seeds implantation treatment in patients with unresectable pancreatic cancer.

METHODS

Thirty-one patients with inoperable pancreatic cancer were enrolled in this study. The 125I seeds were implanted into pancreatic tumor under CT guidance. In addition, 10 patients received routine gemcitabine and 5-fluorouracil chemotherapy 1 week after brachytherapy. Median diameter of the tumor was 5.8 cm.

RESULTS

Follow-up period was 2 to 25 months. Symptoms of refractory pain were significantly resolved post-interventionally (P < 0.05), and Karnofsky physical score increased dramatically (P < 0.05). Tumor response which was demonstrated on repeated CT film 2 months post-treatment revealed complete response (CR) in 3 cases, partial response (PR) in 16 cases, stable disease (SD) in 9 cases, and progressive disease (PD) in 3 cases. Overall responding rate (CR+PR) was 61.3%. Median survival time for all patients was 10.31 months. Two seeds of radioactive 125I migrated to the liver in 2 patients. There were no serious complications detected during the follow-up period.

CONCLUSIONS

This study suggests that CT-guided brachytherapy using 125I seeds implantation appears to be safe, effective, uncomplicated, and could produce adequate pain relief for treating unresectable pancreatic cancer.

Sequential Treatment of Superior Vena Cava Syndrome Caused by of Non-small Cell Carcinoma Lung Cancer (NSCLC) with Vascular Stenting and Iodine-125 Implantation

Feasibility and efficacy of sequentially performed endovascular stenting and Iodine-125 brachytherapy for malignant superior vena cava syndrome (SVCS) were evaluated. Thirty-four patients with malignant SVCS caused by NSCLC underwent sequential treatment of endovascular stenting and Iodine-125 brachytherapy. SVCS was diagnosed in all patients by CT images or vena-cavography. Pathology diagnosis was acquired by image guided biopsy. Endovascular stent placement was performed as first-line treatment for symptom relief. CT-guided Iodine-125 seed implantation performed 24hr after stenting. Clinical end points were resolution of symptoms and local efficacy of primary malignancy regression. Symptom relief rate was >90% after 24hr and 97% after 3 months. No migration of seeds or restenosis occurred in any patient. The local efficacy (defined as either partial or complete response) was 53%, 79%, 88% and 74% after 1, 3, 6 and 12months, respectively. Mean SVCS-free survival time was 305 days (range 120–960 days). Two patients were still alive at the time of this writing, Thirty-one died from progression and one died from acute heart disease. Sequentially performed endovascular stenting and Iodine-125 brachytherapy provides a safe and effective alternative for malignant SVCS caused by NSCLC.