Stereotactic Brachytherapy Research Articles

Beyond surgical resection: evaluating stereotactic brachytherapy iodine-125 for low-grade gliomas: a systematic review and meta-analysis.

Stereotactic Brachytherapy Iodine-125 (SBT I-125) has been investigated by some studies for the treatment of lowgrade gliomas. We performed a meta-analysis to assess the efficacy and safety of SBT I-125 Brachytherapy for treatment of patients with Low-Grade Gliomas. PubMed, Cochrane, Web of Science, and EMBASE databases were searched for randomized and observational studies. This systematic review and meta-analysis was conducted according to the Cochrane Collaboration and the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) statement guidelines. We used relative risk (RR) with 95% confidence intervals and random effects model to compare the effects of I-125 SBT treatment on the interest outcomes. We evaluated heterogeneity using I2 statistics; we considered heterogeneity to be significant if the p-value was less than 0.05 and I2 was higher than 35%. We performed statistical analysis using the software R (version 4.2.3). A total of 20 studies with a cohort of 988 patients with low grade gliomas who received SBT I-125 as a treatment option. The pooled analysis evidenced: (1) Complication rate of 10% (95% CI: 7-12%; I² = 60%); (2) 5-year PFS of 66% (99% CI: 45-86%; I²= 98%); (3) 10-year PFS was 66% (99% CI: 45-86%; I²= 98%); (4) Malignant transformation rate of 26% (95% CI: 8-45%; I²=0); (5) Mortality of 33% (95% CI: 15-51%; I² = 0%). Our systematic review and meta-analysis of SBT I-125 for low-grade gliomas have revealed significant concerns regarding its safety and efficacy. Despite a proportion of patients remaining progression-free, elevated rates of complications and mortality cast doubt on the intervention's reliability. Future research should prioritize long-term follow-up studies, standardized protocols, and comparative effectiveness research.

Stereotactic Iodine-125 Brachytherapy for Low-Grade Glioma Treatment: A Monte Carlo study

Background: Stereotactic brachytherapy is an appropriate method that has been used for brain tumors and metastases treatment for more than 40 years for many patients in the world. Also, iodine-125 brachytherapy has been utilized in brain tumors for interstitial brachytherapy treatment since 1979. Even though the physical and biological features make these implants particularly attractive for minimal invasive treatment, the main goal of this paper is to evaluate the I-125 seed time and dose reached to brain glioma tumors of different sizes for treatment using Monte Carlo modeling. Methods: In this paper, Monte Carlo simulation has been applied by the Gate code with 20 (MBq) activity for an iodine seed design for low-grade glioma tumors treatment. Dosimetry features of this source were defined by the updated TG-43U1 recommendations. The absorbed dose distribution around the seed was calculated using the Gate code in liquid water. Result: The ideal condition for brachytherapy is for tumors smaller than 4 cm. With a larger tumor size, the absorption dose at the border of tumor and healthy tissue will be decreased and the implantation time for seeds will increase. Conclusion: Placing an iodine-125 source inside the tumor is not sufficient because of the non-uniform dose distribution in the tumor and the length of treatment time. Using four iodine-125 sources eliminates the tumor, and also, a uniform dose distribution is created in the tumor and the implantation time will be reduced, respectively.

Uloga stereotaksične radioterapije u lečenju metastaza u jetri kolorektalnog karcinoma

Colorectal cancer is third most common malignant disease and second leading cause of cancer-related deaths worldwide. In 2020, there were 5900 new cases in Serbia and around 3300 number of deaths related to this disease. Metastatic disease is most frequently located in liver. Surgery is first option if complete resection of liver metastases is achievable. Since liver metastases are resectable in 10 - 20% of cases, there is a possibility of implementation of other treatment modality. Alternative for surgery in local treatment of unresectable metastases are stereotactic body radiation therapy (SBRT), interstitial and intraluminal brachytherapy, transarterial chemoembolization, hepatic arterial infusion chemotherapy, selective internal radiation therapy with yttrium-90 resin microspheres, cryoablation, radiofrequency, chemical, and microwave ablation. Candidates for SBRT are patients with unresectable liver metastatic disease and patients with comorbidities which disable surgical treatment, with adequate function of uninvolved liver tissue. Respiration induced motion of target volume can be reduced by introduction of motion management strategies such as infrared markers, deep inspiration breath hold, abdominal compression, respiratory tracking and gating. CyberKnife, TomoTherapy machine and modified linear accelerators are used for delivering SBRT. These units allow us to deliver dose more precisely and to make dose escalation. Different regimes of fractionation are optional, from single fraction to hypo fractionation regimes, and doses are typically around 30 - 60 Gy in 3 fractions. Low toxicity rates in patients with liver metastases treated with SBRT are in relation with precise treatment planning, dose prescription and fractionation. Results of research suggest that delivery of large doses can provide high rate of local response, but on the other hand there is possibility of disease progression out of target volumes. With adequate selection of patients with unresectable liver metastases, the implementation of SBRT, especially in combination with effective systematic treatment modalities, can provide better local control with extension of survival.

Radiation necrosis after a combination of external beam radiotherapy and iodine-125 brachytherapy in gliomas

PurposeFrequency and risk profile of radiation necrosis (RN) in patients with glioma undergoing either upfront stereotactic brachytherapy (SBT) and additional salvage external beam radiotherapy (EBRT) after tumor recurrence or vice versa remains unknown.MethodsPatients with glioma treated with low-activity temporary iodine-125 SBT at the University of Munich between 1999 and 2016 who had either additional upfront or salvage EBRT were included. Biologically effective doses (BED) were calculated. RN was diagnosed using stereotactic biopsy and/or metabolic imaging. The rate of RN was estimated with the Kaplan Meier method. Risk factors were obtained from logistic regression models.ResultsEighty-six patients (49 male, 37 female, median age 47 years) were included. 38 patients suffered from low-grade and 48 from high-grade glioma. Median follow-up was 15 months after second treatment. Fifty-eight patients received upfront EBRT (median total dose: 60 Gy), and 28 upfront SBT (median reference dose: 54 Gy, median dose rate: 10.0 cGy/h). Median time interval between treatments was 19 months. RN was diagnosed in 8/75 patients. The 1- and 2-year risk of RN was 5.1% and 11.7%, respectively. Tumor volume and irradiation time of SBT, number of implanted seeds, and salvage EBRT were risk factors for RN. Neither of the BED values nor the time interval between both treatments gained prognostic influence.ConclusionThe combination of upfront EBRT and salvage SBT or vice versa is feasible for glioma patients. The risk of RN is mainly determined by the treatment volume but not by the interval between therapies.

Computerized tomography-Guided Microwave Ablation of Patients with Stage I Non-small Cell Lung Cancers: A Single-Institution Retrospective Study.

Objectives:The objective of the study was to retrospectively investigate the safety and efficacy of computerized tomography-guided microwave ablation (MWA) in the treatment of Stage I non-small cell lung cancers (NSCLCs).Material and Methods:This retrospective, single-center study evaluated 21 patients (10 males and 11 females; mean age 73.8 ± 8.2 years) with Stage I peripheral NSCLCs treated with MWA between 2010 and 2020. All patients were surveyed for metastatic disease. Clinical success was defined as absence of FDG avidity on follow-up imaging. Tumor growth within 5 mm of the original ablated territory was defined as local recurrence. Welch t-test and Fisher’s exact test were used for univariate analysis. Hazard ratio (HR) and odds ratio (OR) were determined using Cox regression and Firth logistic regression. Significance was P < 0.05. Data are expressed as mean ± standard deviation.Results:Ablated tumors had longest dimension 17.4 ± 5.4 mm and depth 19.7 ± 15.1 mm from the pleural surface. Median follow-up was 20 months (range, 0.6–56 months). Mean overall survival (OS) following lung cancer diagnosis or MWA was 26.2 ± 15.4 months (range, 5–56 months) and 23.7 ± 15.1 months (range, 3–55 months). OS at 1, 2, and 5 years was 67.6%, 61.8%, and 45.7%, respectively. Progression-free survival (PFS) was 19.1 ± 16.2 months (range, 1–55 months). PFS at 1, 2, and 5 years was 44.5%, 32.9%, and 32.9%, respectively. Technical success was 100%, while clinical success was observed in 95.2% (20/21) of patients. One patient had local residual disease following MWA and was treated with chemotherapy. Local control was 90% with recurrence in two patients following ablation. Six patients (28.6%) experienced post-ablation complications, with pneumothorax being the most common event (23.8% of patients). Female gender was associated with 90% reduction in risk of death (HR 0.1, P = 0.014). Tumor longest dimension was associated with a 10% increase in risk of death (P = 0.197). Several comorbidities were associated with increased hazard. Univariate analysis revealed pre-ablation forced vital capacity trended higher among survivors (84.7 ± 15.2% vs. 73 ± 21.6%, P = 0.093). Adjusted for age and sex, adenocarcinoma, and neuroendocrine histology trended toward improved OS (OR: 0.13, 0.13) and PFS (OR: 0.88, 0.37) compared to squamous cell carcinoma.Conclusion:MWA provides a safe and effective alternative to stereotactic brachytherapy resulting in promising OS and PFS in patients with Stage I peripheral NSCLC. Larger sample sizes are needed to further define the effects of underlying comorbidities and tumor biology.

Long-term outcome of stereotactic brachytherapy with temporary Iodine-125 seeds in patients with WHO grade II gliomas

BackgroundThis long-term retrospective analysis aimed to investigate the outcome and toxicity profile of stereotactic brachytherapy (SBT) in selected low-grade gliomas WHO grade II (LGGII) in a large patient series.MethodsThis analysis comprised 106 consecutive patients who received SBT with temporary Iodine-125 seeds for histologically verified LGGII at the University of Munich between March 1997 and July 2011. Investigation included clinical characteristics, technical aspects of SBT, the application of other treatments, outcome analyses including malignization rates, and prognostic factors with special focus on molecular biomarkers.ResultsFor the entire study population, the 5- and 10-years overall survival (OS) rates were 79% and 62%, respectively, with a median follow-up of 115.9 months. No prognostic factors could be identified. Interstitial radiotherapy was applied in 51 cases as first-line treatment with a median number of two seeds (range 1–5), and a median total implanted activity of 21.8 mCi (range 4.2–43.4). The reference dose average was 54.0 Gy. Five- and ten-years OS and progression-free survival rates after SBT were 72% and 43%, and 40% and 23%, respectively, with a median follow-up of 86.7 months. The procedure-related mortality rate was zero, although an overall complication rate of 16% was registered. Patients with complications had a significantly larger tumor volume (p = 0.029).ConclusionSBT is a minimally invasive treatment modality with a favorable outcome and toxicity profile. It is both an alternative primary treatment method as well as an adjunct to open tumor resection in selected low-grade gliomas.

Stereotactic Pelvic Brachytherapy With HDR Boost for Dose Escalation in High Tier Intermediate and High Risk Prostate ca

Stereotactic Pelvic Brachytherapy With HDR Boost for Dose Escalation in High Tier Intermediate and High Risk Prostate ca

What is the quality of hydrogel spacer insertions? and which patients will benefit? A literature review

AbstractAim:To evaluate the quality of rectal hydrogel spacer (HS) insertions from literature in patients undergoing radical radiotherapy for prostate cancer. The secondary aim is to assess the benefit of HSs in patients with risk factors more likely to have rectal complications, such as non-conventional radiotherapy dose fractionations and high-risk disease.Method and materials:A literature search of peer-reviewed electronic articles was carried out using Boolean connectors and Medical Subject Headings in the databases. Databases searched included ScienceDirect, Medline and Cinahl. The articles were assessed using relevant critical appraisal skills programme tools.Results:From the 26 studies used, HS showed a clinically significant relative reduction in rectal planning dose volumes for both high- and low-risk prostate cancer patients in a range of radiotherapy treatment modalities including volumetric modulated arc therapy, intensity-modulated radiotherapy, intensity-modulated proton therapy, stereotactic ablative body radiotherapy and brachytherapy. Spacer placements were successfully inserted in 99% of patients. However, rectal wall infiltration occurrence was 6% and ≥2 cm unsymmetrical placements in 2%.Findings:A spacer scoring system based on the HS symmetry has provided evidence of the quality of the position inserted, which was visually aided by T2-wieghted MRIs. Despite optimal HS placements ranging from 62 to 72%, HS had a clinically significant reduction of ≥25% in planned rectal V70 dose in 97% of patients.

Novel CT-guided 188-rhenium brachytherapy device for local primary and secondary lung malignancies.

96 Background: Stereotactic brachytherapy for extensive local tumors offers a very effective treatment option locally without significant complications in medically impaired patients. In this context, we have recently developed a new potential anticancer agent from Poly-L-Lysins dendrimer as a delivery nano system loaded with diffusible Imidazolic probes complexed with 188-Rhenium for targeting in particular hypoxic tumors resistant to conventional cancer treatments. The aim of the study is assessment the safety profile and therapeutic efficacy of anticancer agent derived from [188Re]rhenium-ligand as radioactive ligand loaded 5th generation poly-L-lysine dendrimer in patients with unresectable Lung Malignancies. Methods: The experiment agent “ 188Re-ImDendrim” is consisting of 5th generation poly-L-lysine dendrimer (20 nM) mixed with nitro-imidazole-methyl-1,2,3-triazol-methyl-di-(2-pycolyl) amine at GMP grade and labelled with [188Re]-rhenium. The study was approved by Shanghai East Hospital ethics committee. 5 patients received “188Re-ImDendrim” directly into lung tumors under CT-guidance, at an activity level of 162 MBq/cc of tumor (range 2 to 7 cm; mean diameter, 4 cm) . For voluminous tumors ( &gt; 65 cc) the dose is given in divided injection spaced 2 weeks apart (Tumor of 115cc: 2 administrations, Tumor of 180 cc: 3 administrations). At H0.5, H 4, H24, H36 , H72 post-administration, the patient get a SPECT control. The response to treatment is evaluated thanks to PET/CT Standardized Uptake Values (SUVs). Results: Stereotactic administrations of “188-Rhenium-ImDendrim” were successfully carried out in all patients under local anesthesia. The radioactive product diffuses homogeneously in the tumor volume and remains 72 hours post-administration with no significant diffusion out site of injection. The One of the 5 patients reported discrete transitive hemoptysis as adverse events. All targeted tumors were responding at 12 weeks, with two complete responses. Conclusions: Percutaneous single and iterative administrations of this novel 188-Rhenium-Imdendrim brachytherapy device into lung cancers are safe and well tolerated. The initial data on therapeutic response are promising. Clinical trial information: EC.D (BG) 016.03.1.

Preliminary observation of the safety of template-assisted 192Ir source hypofractionated stereotactic ablative brachytherapy for locally advanced non-small cell lung cancer

Objective To preliminarily evaluate the safety of the coplanar template-assisted 192Ir hypofractionated stereotactic ablative brachytherapy (SABT) in patients with locally advanced non-small cell lung cancer (LA-NSCLC), and assess the effect of template-assisted technology upon the accuracy of SABT by comparing the consistency of dosimetric parameters between preoperative and operative plans. Methods Fifteen patients histologically confirmed with LA-NSCLC (stage ⅡB-ⅢA) were recruited and received the template-assisted SABT delivered in a risk-adapted fractionation (30 Gy/1F). Preoperative planning, template-assisted needle implantation, operative planning and implementation were performed in all patients. Dosimetric results of preoperative and operative plans were statistically compared by assessing the dosimetric parameters of gross tumor volume (HI, CI, D90, V100 and V150) and organ at risk(V5, V20 and mean dose of bilateral lung, D2cc of spinal cord. The incidence of perioperative complications of SABT was recorded. The safety and feasibility of SABT were evaluated. Results Slight changes were noted in terms of target dose and irradiated dose to the lung between preoperative and operative plans without statistical significance (both P>0.05). No severe adverse events, such as severe pneumothorax, hemothorax and hemoptysis were observed. Conclusions Application of the template-assisted SABT can enhance the accuracy of implantation, maintain the consistency of the dosimetric parameters between the preoperative and operative plans and guarantee the clinical efficacy. Key words: Lung neoplasm/Brachytherapy; Coplanar-template; Safety

Role of Radiotherapy in Localized Prostate Cancer

Radiation is a standard treatment approach in the treatment of prostate cancer, in either a definitive or postoperative setting. There is mounting evidence of improved cancer outcomes with higher doses of radiation in all risk categories, including low-risk prostate cancer patients. Technical advances with the emergence of inverse planning intensity-modulated techniques combined with image guidance have allowed for dose escalation using external-beam radiation therapy (EBRT). However, despite more accurate treatment delivery, dose-escalated radiation has consistently translated into increased toxicity. Stereotactic body radiotherapy and brachytherapy offer great means of dose escalation to the prostate without increasing the dose to the surrounding organs. Radiation options for low-risk patients include hypofractionated EBRT and brachytherapy monotherapy. Intermediate-risk patients can be divided into favorable and unfavorable groups. For favorable-risk disease, monotherapeutic approaches could be considered, whereas for unfavorable intermediate-risk and high-risk disease, a combination of therapies must be considered. In the postoperative setting, adjuvant radiation improves biochemical outcomes in patients with adverse pathologic features (pT3 and/or positive margins). This review contains 2 figures, 5 tables, 1 video and 135 refereces Key words: prostate cancer, radiation therapy, brachytherapy, stereotactic ablative body radiation, hypofractionation, hormonal therapy

A Comparative Study of Quality of Life in Patients with Low-and Intermediate-Risk Prostate Cancer: Stereotactic Radiotherapy vs. High Dose-Rate Brachytherapy Monotherapy vs. High Dose-Rate Brachytherapy Boost

A Comparative Study of Quality of Life in Patients with Low-and Intermediate-Risk Prostate Cancer: Stereotactic Radiotherapy vs. High Dose-Rate Brachytherapy Monotherapy vs. High Dose-Rate Brachytherapy Boost

Small renal cell carcinoma-active surveillance and ablation

The incidence of renal cell carcinoma has been rising for years. At the same time there is an increasing prevalence of chronic renal failure with subsequent higher morbidity and shorter life expectancy in those affected. In the last decades the gold standard has thus shiftedfrom radical to partial nephrectomy or tumor enucleation. Atreatment alternative can be advantageous for selected patients with high morbidity and an increased risk of complications in anesthesia or surgery. Active surveillance represents acontrolled delay in the initiation of treatment with a curative intention. Percutaneous radiofrequency ablation and laparoscopic cryoablation are currently the most commonly used treatment alternatives. Newer ablation procedures, such as high-intensity focused ultrasound, irreversible electroporation, microwave ablation, stereotactic ablative radiotherapy and high-dose brachytherapy have a high potential in some cases but are still considered experimental for the treatment.

Role of Radiotherapy in Localized Prostate Cancer

Radiation is a standard treatment approach in the treatment of prostate cancer, in either a definitive or postoperative setting. There is mounting evidence of improved cancer outcomes with higher doses of radiation in all risk categories, including low-risk prostate cancer patients. Technical advances with the emergence of inverse planning intensity-modulated techniques combined with image guidance have allowed for dose escalation using external-beam radiation therapy (EBRT). However, despite more accurate treatment delivery, dose-escalated radiation has consistently translated into increased toxicity. Stereotactic body radiotherapy and brachytherapy offer great means of dose escalation to the prostate without increasing the dose to the surrounding organs. Radiation options for low-risk patients include hypofractionated EBRT and brachytherapy monotherapy. Intermediate-risk patients can be divided into favorable and unfavorable groups. For favorable-risk disease, monotherapeutic approaches could be considered, whereas for unfavorable intermediate-risk and high-risk disease, a combination of therapies must be considered. In the postoperative setting, adjuvant radiation improves biochemical outcomes in patients with adverse pathologic features (pT3 and/or positive margins). This review contains 2 figures, 5 tables, 1 video and 135 refereces Key words: prostate cancer, radiation therapy, brachytherapy, stereotactic ablative body radiation, hypofractionation, hormonal therapy

Long-term outcomes of stereotactic intracavitary brachytherapy for cystic craniopharyngiomas

Objective To assess the long-term outcomes of stereotactic intracystic brachytherapy for the treatment of cystic craniopharyngiomas. Methods A total of 141 consecutive patients with cystic craniopharyngioma treated by stereotactic intracystic phosphorus-32 at Department of Neurosurgery, Navy General Hospital of PLA from January 1996 to December 2015. There were 85 males and 56 females and the mean age was 40.1 years (range: 3-72 years). The calculated cumulative beta dose aimed at the inner surface of the cyst wall was 250 Gy. Results All patients were followed up for 1.0-19.5 years with an average of 9.7±4.5 years. The decreased visual acuity had improved in 68.6% (59/86) of the patients in long-term result. The total tumor response rate was 86.5% (122 cases) including the total response accounting for 44.0% (62 cases), partial response accounting for 36.2% (51 cases) and stable response accounting for 6.3% (9 cases). The rate of no response was 13.5% (19 cases). The recurrence rate was 17% (24 cases). The side effects that occurred during follow-up period included worsening of visual acuity in 13 (9.2%), the third nerve palsy in 2 (1.4%), internal carotid artery occlusion in 1(0.7%), new-onset sexual dysfunction in 5 (3.5%), diabetes insipidus in 7 (5.0%), obesity in 12 (8.5%) and cognitive dysfunction in 10 (7.1%) patients, respectively. The late complication rate was 35.5% (50/141). The mean survival after treatment was 120 months. The actuarial 5-, 10- and 15-yr survival rates were 97.9% (138 cases), 92.9% (131 cases) and 89.3% (126 cases), respectively. Conclusion Stereotactic intracavitary brachytherapy is a valuable treatment alternative for cystic craniopharyngioma, particularly for patients with high surgical risk and recurrent tumors. Key words: Cystic craniopharyngioma; Stereotactic radiosurgery; Phosphorus radioisotopes; Treatment outcome; Long-term

Evaluation of Organ-At-Risk (OAR) Sparing in Vaginal Cuff Boost Treatment for Endometrial Cancer using Stereotactic Body Radiotherapy (SBRT) and Brachytherapy

Evaluation of Organ-At-Risk (OAR) Sparing in Vaginal Cuff Boost Treatment for Endometrial Cancer using Stereotactic Body Radiotherapy (SBRT) and Brachytherapy

Stereotactic brachytherapy using iodine 125 seeds for the treatment of primary and recurrent anaplastic glioma WHO° III.

The current study analyzed the outcome after stereotactic brachytherapy (SBT) using iodine-125 seeds in anaplastic astrocytoma, oligoastrocytoma or oligodendroglioma not suitable for resection. Out of 223 patients harbouring a malignant glioma treated according to a prospective protocol, 172 patients were selected who received SBT to treat a WHO grade III de-novo/residual tumor (n = 99) or a tumor recurrence after multimodal treatment (n = 73). We assessed progression free survival (PFS), overall survival (OS), radiological and clinical outcome and determined prognostic factors using univariate and multivariate regression analyses. The median follow-up time was 38months. Median OS and median PFS was 28.9 and 21.4 months in the de-novo group vs. 49.4 and 32.6months in the recurrence group. Recurrent tumors had more frequently (p = 0.01) an oligodendroglial-component compared to de novo tumors. According to cohort-specific univariate analyses KPS at SBT had a significant (p = 0.008) impact on OS in the de-novo group. In the recurrence group, (Cox regression analysis) OS was significantly associated with histology subtype (oligoastro-/oligodendroglioma vs. astrocytoma, p = 0.043). Transient and permanent morbidity (~1 %) was low. For patients unable to undergo surgery due to eloquent tumour location or reduced general condition SBT is an effective treatment option, which does not foreclose additional therapeutic interventions.

Dose Distribution and Dose Enhancement by Using Gadolinium Nanoparticles Implant in Brain Tumor in Stereotactic Brachytherapy

BackgroundThe photoelectric and pair production processes increase when high-energy photons interact with materials with high atomic number Z. The energy loss results in a dose enhancement at the target implanted with these materials. This will lead to a higher active dose to be delivered to tumor, while sparing healthy tissues around the target volume. Objective and methodThe objective of this work was to compute the radial dose enhancement, using GEANT4 based Monte Carlo simulations, at and near a 1×1×1cm3 brain tumor implanted with different concentrations of gadolinium nanoparticles when using 192Ir, 137Cs and 60Co, brachytherapy sources with parallel beam geometry. ResultsOur outcomes show a dose enhancement factor of 1.45 for a concentration of 70mg of gadolinium in the tumor when irradiated with 0.38MeV γ-photon from 192Ir source. It was also observed that this dose enhancement increased with increasing gadolinium concentration in the target and with photon energy. ConclusionGadolinium nanoparticles are groundbreaking agents with strong advantageous potential in cancer radiotherapy due to the fact that they enhance the radiation dose within the tumor.

Application of radiotherapy in perioperative comprehensive treatment for the elderly with rectal cancer

Considered that most of the phase II or III clinical trials contain less elderly patients or only contain those who had good health status, these results might not be applied in those elderly patients with some complex status. The patients of 70 years old or more usually have complications or worse organ function, thus the standard treatment for them becomes a gray zone. In rectal cancer patients, the rate of elderly patients receiving standard chemoradiotherapy (CRT) is obviously lower than that of the younger ones. More and more retrospective studies found that the prognosis of the elderly (≥70) who received neo-adjuvant or adjuvant CRT was better than that of those who received surgery or radiotherapy only, and the outcome of the above-mentioned elderly was similar to those of other phase III trial or younger patients with good tolerance. In addition, some studies revealed patients with good status, less or slight complications had a better prognosis. The advance of radiation therapy, such as Image-guided Radiation Therapy (IGRT), Intensity-modulated Radiation Therapy (IMRT), Stereotactic Body Radiation Therapy (SBRT), brachytherapy and particle therapy, will benefit the elderly cancer patients. We think that treatments recommended to the elderly will become more personalized.

RTRB-19LOW-DOSE RATE STEREOTACTIC BRACHYTHERAPY IN RECURRENT HIGH GRADE GLIOMA: FEASIBILITY AND OUTCOME IN 227 PATIENTS

BACKGROUND: Despite several advances in the management of malignant glioma, treatment options in case of tumor recurrence after multimodal treatment are limited. The present study reports feasibility and outcome of low-dose rate stereotactic brachytherapy (SBT) with iodine 125 seeds in a patient cohort with inoperable circumscribed recurrent WHO III or IV gliomas. METHODS: Patients with either an anaplastic glioma or glioblastoma who received SBT in case of a tumor recurrence were retrospectively analyzed. SBT was performed according to a prospective protocol established since 1990 at our institution* using iodine-125 seeds for low dose rate implantation. Tumor recurrence was verified histologically prior to seed implantation in all patients. Survival analysis was performed using Cox-regression models to identify prognostic factors for post-recurrence survival (PRS). RESULTS: A total number of 227 patients (83 WHO III and 144 WHO IV) were included. Median follow-up time was 132.2 months. Age at implantation was 49.5 years, Karnofsky performance score (KPS) was 80%, tumor surface dose was 60 Gy and the tumor volume was 17.8 cm3 (median). Median PRS was 14.0 (CI95% 12.4-15.7) months in the entire group; 28.0 (CI 95% 20.2.-35.9) months for WHO III and 11.3 (CI95% 8.8-12.9) months for WHO IV tumors (log rank p <0.0001). In the Cox regression analysis, variables associated with improved PRS following SBT were WHO III histology (p <0.0001), lower age (p = 0.004), higher KPS (p = 0.0017) and lower seed activity (p = 0.027). No permanent morbidity occurred; transient morbidity was observed in 6.9 % of all patients. CONCLUSIONS: In patients with a circumscribed high grade glioma recurrence following multimodal therapy, SBT is a safe and effective therapy option permitting further salvage therapies. *institution of affiliation Nr. 2