High-dose-rate Interstitial Brachytherapy Research Articles

144: Dosimetric Evaluation of a New RT Technique Combining Stereotactic Body Radiotherapy (SBRT) to HDR Interstitial Brachytherapy (ISBT) as Boost for Locally Advanced Cervical Cancers

144: Dosimetric Evaluation of a New RT Technique Combining Stereotactic Body Radiotherapy (SBRT) to HDR Interstitial Brachytherapy (ISBT) as Boost for Locally Advanced Cervical Cancers

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.

Effect of 3-Dimensional Interstitial High-Dose-Rate Brachytherapy With Regional Metastatic Lymph Node Intensity-Modulated Radiation Therapy in Locally Advanced Peripheral Non-Small Cell Lung Cancer: 5-Year Follow-up of a Phase 2 Clinical Trial

We aimedto reveal the 5-year clinical outcomes of 3-dimensional (3D) interstitial high-dose-rate (HDR) brachytherapy with regional metastatic lymph node intensity modulated radiation therapy (IMRT) for locally advanced peripheral non-small cell lung cancer (NSCLC), which has been shown to have low toxicity and improved 2-year survival rates in patients with this disease. In this phase 2, single-arm, open-label clinical trial, 83 patients with locally advanced peripheral NSCLC were enrolled (median follow-up [range], 53.7 [4.3-120.4] months). All eligible patients received 3D interstitial HDR brachytherapy with regional metastatic lymph node IMRT. The primary endpoint was overall survival (OS). Secondary endpoints were local recurrence-free survival, regional recurrence-free survival, progression-free survival, distant metastasis-free survival, toxicities, and quality of life. The final analysis included 75 patients (19 [25.3%] females, 56 [74.7%] males; median [range] age, 64 [44-80] years; stage IIIA, 34 [45.3%]; stage IIIB, 41 [54.7%]). At the latest follow-up, 32 (42.7%) patients had survived. The median OS was 38.0 months (5-year OS, 44.5%; 95% confidence interval [CI], 33.8%-58.6%). Local recurrence-free survival, recurrence-free survival, and distant metastasis-free survival at 5 years were 79.2% (95% CI, 68.5%-91.5%), 73.6% (95% CI, 61.5%-88.1%), and 50.3% (95% CI, 38.3%-66.1%), respectively. The dominant failure pattern was distant disease, corresponding to 40% (30 of 75) of patients and 65.2% (30 of 46) of all failures. Two (2.7%) patients developed grade 1 acute pneumonitis. Grade 2 and 3 acute esophagitis occurred in 11 (14.7%) and 4 (5.3%) patients, respectively. No late radiation-related grade ≥2 late adverse events were observed. 3D interstitial HDR brachytherapy with regional metastatic lymph node IMRT for locally advanced peripheral NSCLC shows significant OS and has a low toxicity rate. Additional evaluation in a phase 3 trial is recommended to substantiate these findings.

Salvage image-guided freehand interstitial brachytherapy for pelvic sidewall recurrence after hysterectomy for uterine malignancies

Pelvic sidewall recurrence after hysterectomy for uterine malignances has a poor prognosis, and the salvage therapy for this type of recurrence is still challenging. The purpose of this study was to investigate the efficacy of freehand high-dose-rate interstitial brachytherapy (HDR-ISBT) through the perineum using transrectal ultrasonography for this disease. We retrospectively evaluated 42 patients with pelvic sidewall recurrence after hysterectomy for uterine cervical and endometrial cancers. We investigated patients' characteristics, the 2-year local control and survival rates, and late adverse events of the rectum and bladder. The 2-year overall survival, local control, and progression-free survival rates were 73.7% (95% confidence interval [CI], 60.8-89.3%), 69.4% (95% CI, 55.4-80.1%), and 37.3% (95% CI, 24.6-56.5%), respectively. In Cox multivariate analysis, tumor size at recurrence (<45 mm vs.≥45 mm) (p = 0.04) and disease-free periods after hysterectomy (<10 months vs. ≥10 months) (p < 0.01) were significant prognostic factors for overall survival. Lymph node metastasis at recurrence (p < 0.01) was also a significant prognostic factor for progression-free survival. Three patients experienced Grade 3-4 late proctitis (7%). Transperineal freehand salvage HDR-ISBT using transrectal ultrasonography was demonstratedto be a curative treatment option for patients with pelvic sidewall recurrence following hysterectomy. Based on the findings of this study, we emphasize the importance of HDR-ISBT for pelvic sidewall recurrence.

Feasibility of accelerated image-guided high-dose-rate interstitial brachytherapy with inverse planning simulated annealing (IPSA-HDRBT) for post-operative treatment of pathologically node-negative squamous cell carcinomas of the oral tongue

Inverse planning simulated annealing (IPSA) produces highly conformal dose distributions and quick optimizations for high-dose-rate interstitial brachytherapy (HDRBT). We report our dosimetry and overall outcomes using this approach for the accelerated post-operative treatment of pathologically node-negative squamous cell carcinomas of the oral tongue (OTSCC) with high risk of local recurrence. Patients with newly diagnosed pN0 OTSCC treated with partial glossectomy, neck dissection, and post-operative HDRBT alone from 2007 to 2021 were retrospectively reviewed. Patients received 30 Gy in 5 fractions over 2.5 days. Target volume and mandible dosimetry are reported. Actuarial rates of local control, regional control, disease-specific survival, and overall survival were estimated using the Kaplan-Meier method. Toxicity was categorized using the Common Terminology Criteria for Adverse Events (CTCAE) version 5.0. 19 consecutive patients were reviewed. Median follow-up was 3.2 years (IQR 1.4-8.2 years) with a 3-year estimated local control rate of 81%. Target volumes were generally small, as the median volume was 12.66 cc. Median V150% and V200% were 52% and 24%, respectively. D1cc and D2cc to the mandible were 17.31 Gy and 14.42 Gy, respectively. IPSA-HDRBT is feasible and highly efficient for post-operative treatment of the primary tumor bed in patients with pathologically node-negative squamous cell carcinomas of the oral tongue. Further technical optimization and prospective clinical evaluation in a larger patient cohort are planned.

Correlation of chemokines and growth factors with radiation-induced liver injury after interstitial high dose rate (HDR) brachytherapy of liver metastases

BackgroundLocoregional therapies, as imaging-guided tumor-directed procedures, are emerging treatment strategies in the management of primary and secondary liver malignancies such as e.g. colorectal cancer liver metastases. As one of those, irradiation-based interstitial high dose rate brachytherapy (iBT) of liver metastases bears a risk of developing focal radiation-induced liver injury (fRILI). Since little is known about biological factors involved in hepatic dysfunction after irradiation, the aim of this study was to identify factors, that may play a role in the underlying mechanism of fRILI, and that potentially may serve as biomarkers for post-therapeutic fRILI to improve specific management and treatment of patients.MethodsTwenty-two patients with hepatic malignancies (tumor patients, TP) underwent iBT with total ablative doses of radiation to the target volume ranging from e.g. 15 to 25 Gy. Hepatobiliary magnetic resonance imaging (MRI) was performed 6 weeks after iBT to quanitify fRILI. Blood samples were taken before (pre) and 6 weeks after (post) iBT from TP, and from ten healthy volunteers (HV controls) for the analyses of humoral mediators: monocyte chemoattractant protein-1 (MCP-1), chemokine (C-X3-C motif) ligand 1 (CX3CL1), vascular endothelial growth factor (VEGF) and beta-nerve growth factor (beta-NGF) using the Multi-Analyte Flow Assay via flow cytometry. Correlation analyses between the humoral mediators (pre and post iBT) with the tumor volume and fRILI were performed.ResultsWhile MCP-1 and CX3CL1 tended to decrease in TP vs. HV, VEGF was significantly decreased in TP vs. HV pre and post iBT (p < 0.05). Beta-NGF levels were significantly increased in TP vs. HV pre and post iBT (p < 0.05). Baseline circulating levels of MCP-1, VEGF and beta-NGF have shown significant positive correlations with the hepatic tumor volume (p < 0.05). Circulating levels of humoral mediators before treatment did not correlate with fRILI, while CX3CL1 and VEGF after iBT have shown significant positive correlations with fRILI (p < 0.05).ConclusionTumor volume and threshold dose of irradiation damage correlated positively with MCP-1 and VEGF as well as NGF and CX3CL, respectively. Thus, investigation of biological mediators in blood samples from tumor patients may provide an appropriate tool to predict fRILI after interstitial HDR brachytherapy of liver metastases.

PD-0559 Interstitial HDR Brachytherapy in head and neck carcinomas: experience in COVID pandemic

PD-0559 Interstitial HDR Brachytherapy in head and neck carcinomas: experience in COVID pandemic

PO-1793 Clinical outcomes after interstitial HDR brachytherapy for locally advanced cervical cancer

PO-1793 Clinical outcomes after interstitial HDR brachytherapy for locally advanced cervical cancer

Determination of variation in dosimetric parameters of treatment planning with Co-60 and Ir-192 sources in high dose rate brachytherapy of cervical carcinoma

AimTo determine the differences in dosimetric parameters in patients of intracavitary brachytherapy and interstitial HDR brachytherapy using Co-60 and Ir-192 sources. Materials and methodsComputed tomography (CT) based treatment plans of 20 cervical carcinoma patients treated with intracavitary and interstitial high dose rate brachytherapy were retrospectively studied. Patients were planned using Co-60 and Ir-192 sources, keeping the same dwell positions and dose objectives. The dosimetric parameters such as V100, D90, homogeneity index (HI) and conformal index (CI) for target and D2cc, D1cc and D0.1cc for organs at risk (OAR) were compared for both sources. ResultsFor interstitial brachytherapy plans, HR-CTV mean V100 values for Co-60 and Ir-192-based plans were 97.03 ± 1.93% and 96.42 ± 2.18%, respectively. There was no significant difference found in target coverage (p = 0.370). Ir-192 based plans were more homogeneous (HI = 0.68 ± 0.09) than the Co-60 plans (HI = 0.59 ± 0.10). However, the conformity was similar with both the sources. No significant difference was found between D2cc, D1cc, and D0.1cc values of bladder and rectum. In intracavitary brachytherapy plans, we did not find any significant difference in the dosimetric parameters such as point A values, D90, V100, and OAR doses on comparing plans from both sources. ConclusionThere are no significant differences in dosimetric parameters and no clinical advantage of using Co-60 over Ir-192-based brachytherapy. However, when it comes to cost management, Co-60 has a longer half-life, which reduces the cost of frequent source replacement and disposal.

First pointwise encoding time reduction with radial acquisition (PETRA) implementation for catheter detection in interstitial high-dose-rate (HDR) brachytherapy

PURPOSEA pointwise encoding time reduction with radial acquisition (PETRA) sequence was optimized to detect empty catheters in interstitial (HDR) brachytherapy with clinically acceptable spatial accuracy for the first time. Image quality and catheter detectability were assessed in phantoms, and the feasibility of PETRA's clinical implementation was assessed on a gynecological cancer patient. METHODS AND RESULTSEmpty catheters embedded in a gelatin phantom displayed positive signal on PETRA and more accurate cross-sections than on clinically employed T2-weighted sequences, differing by 0.4 mm on average from their nominal 2 mm diameter. PETRA presented minimal susceptibility differences and a symmetric metal artifact, contrary to the clinical sequences. The PETRA-CT catheter tip position differences assessed by a treatment planning system (TPS) were < 1 mm. PETRA also detected an interstitial template with empty catheters penetrating a poultry phantom and fused very well with CT. Interstitial catheter positional difference between PETRA and CT images was < 1 mm on average, increasing with distance from isocenter. All interstitial catheters and the employed interstitial template were detected on PETRA images of an endometrial adenocarcinoma patient. Empty needles were traceable using a TPS, with higher spatial resolution and more favorable contrast than on T2-weighted images used for contouring. A treatment plan could be produced by combining information from PETRA for catheter detection and from T2-weighted images for tumor and organs delineation. CONCLUSIONSPETRA detected successfully and accurately interstitial catheters in phantoms. Its first clinical implementation shows a potential for MR-only treatment planning in interstitial HDR brachytherapy.

TNF-α Indicates Radiation-induced Liver Injury After Interstitial High Dose-rate Brachytherapy.

The aim of the present study was to determine whether the early systemic markers of inflammation, interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α), respond to high dose-rate (HDR) brachytherapy, and their possible correlation with radiation-induced liver injury of patients with liver metastases. This prospective study included 20 tumor patients (TP) undergoing irradiation-based interstitial HDR brachytherapy (iBT) of liver metastases, who received total radiation ablative doses to the planning target volume ranging from 15 to 25 Gy, depending on the tumor entity. Hepatobiliary magnetic resonance imaging (MRI) was performed 6 weeks after iBT to assess the maximum extent of focal radiation-induced liver injury (fRILI). Furthermore, blood samples for the pro-inflammatory cytokine response were taken one day prior to and 6 weeks after irradiation. IL-6 and TNF-α were measured by flow cytometry. Ten healthy volunteers (HV) were used as control group. Compared to HV, TNF-α was significantly enhanced in TP before and after therapy (p<0.05 for both comparisons), while IL-6 increase at baseline was not statistically significant. HDR brachytherapy significantly reduced IL-6 levels after 6 weeks in TP (p<0.05). IL-6 levels after 6 weeks have shown a significant negative correlation with the tumor volume (r=-0.5606; p=0.0261), while no significant correlation was observed between baseline IL-6 or follow-up IL-6 levels with the fRILI. Baseline TNF-α levels positively correlated with the tumor volume (r=0.4342; p=0.0492), and post treatment TNF-α levels showed a significant correlation with the fRILI (r=0.7404; p=0.0022). TNF-α was correlated with both tumor volume and radiation-induced liver injury; thus, representing a promising biomarker for focal radiation-induced liver injury.

Investigation of in vivo source tracking error thresholds for interstitial and intra-cavitary high-dose-rate cervical brachytherapy.

The purpose of this study was to determine a comprehensive in vivo source tracking error thresholds in high-dose-rate (HDR) brachytherapy for cervical cancer. Achieving this enables the definition of an action level for imminent in vivo source tracking technologies and treatment monitoring devices, preventing clinically relevant changes to the applied dose. Retrospective HDR interstitial (n = 10) and intra-cavitary (n = 20) cervical brachytherapy patients were randomly selected to determine the feasibility of implementing in vivo source tracking error thresholds. A script was developed to displace all dwell positions in each treatment plan, along all major axes from their original position. Dose-volume histogram (DVH) indices were calculated without re-optimization of modified plans to determine the appropriate in vivo source tracking error thresholds in each direction. In vivo source tracking error thresholds were directionally dependent; the smallest were found to be 2 mm in the anterior and posterior directions for both interstitial and intra-cavitary treatments. High-risk clinical treatment volume (HR-CTV) coverage was significantly impacted by displacements of 4 to 5 mm along each axis. Critically, there was a large variation in DVH metrics with displacement due to change in dwell weightings and patient anatomy. Determining the dosimetric impact of dwell position displacement provides a clinical benchmark for the development of pre-treatment verification devices and an action level for real-time treatment monitoring. It was established that an in vivo source tracking error threshold needs to be patient-specific. In vivo source tracking error thresholds should be determined for each patient, and can be conducted with extension of the method established in this work.

Interfraction dose deviation and catheter position in cervical interstitial and intracavitary image guided HDR brachytherapy.

Interstitial and intracavitary gynecological HDR brachytherapy involve precise, localized delivery to targets with high dose gradients, sparing adjacent organs at risk (OAR). Due to the proximity of the rectum, bowel and bladder to the target, deviations in the applicator or catheter with respect to patient anatomy can significantly increase dose to OAR. The magnitude and direction of applicator and catheter migration at each fraction was assessed for template interstitial and tandem and ring (T&R) cohorts. The cohort included twelve gynecological patients with intact cervical lesions treated with external beam and brachytherapy. Pre-treatment CT images were registered to the simulation CT with respect to the target. Treatment catheter positions transformed into the planning CT coordinate system to evaluate localized catheter displacement and dose distributions calculated at each fraction. Dose was evaluated on the planning CT with planning contours and dwell locations at treatment position. Absolute deviation, depth and deflection angle for all patients were 4.6 ± 4.2 mm, -1.4 ± 4.0 mm, and 3.1 ± 2.3° respectively (n = 516 catheter positions for all treatment fractions and patients, mean ± SD). Absolute catheter deviation and deflection magnitude for interstitial treatments increased overall with each subsequent fraction with an overall increase of catheter retraction at each fraction (p < 0.005, n = 492 catheters, Kruskal-Wallis). A target EQD2 D90 reduction of 10 ± 10% and 7.7 ± 8.7% of the planned dose for interstitial and T&R cohorts respectively. There was an overall increase in bladder and rectal doses at each fraction. Catheter tracking in interstitial and intracavitary gynecological treatments with CT imaging revealed significant changes in catheter positioning with respect to the target volume. Overall deviations increased in magnitude with each subsequent fraction in the interstitial treatments. This caused patient dosimetry deviations, including target dose reduction and adjacent OAR doses changes.

Perioperative interstitial high-dose-rate brachytherapy for keloids scar.

PurposeTo evaluate the results of keloids treated with perioperative interstitial high-dose-rate brachytherapy (HDR-BT).Material and methodsA retrospective review of 61 keloids in 51 patients treated with perioperative interstitial HDR-BT was performed. Keloid lesions were treated with 12 Gy in 4 fractions within 48 hours. Time between surgery and brachytherapy was less than 90 minutes. Local failure was defined as recurrence of apparent keloid or symptoms in the same place. Median age of patients was 46 years (range, 20-89 years). Keloid scars were located on the chest (41%), ear lobe (21%), back (1.6%), extremities (11.5%), and mean keloid size was 6.3 cm.ResultsWith a median follow-up of 47.95 months (range, 1-96 months), the recurrence rate was 4.9%, all located on the chest. The multivariate analysis showed no statistically significant relationship between location, scar size, and previously treated lesions with the recurrence rate.ConclusionsThe treatment of keloid scars with perioperative interstitial high-dose-rate brachytherapy achieved excellent results, with a recurrence rate of only 4.9% and excellent cosmetic outcomes, suggesting that this technique might be one of the best options for treating keloids.

Dosimetric predictors of local control and complications in gynecologic transperineal implant patients: The medical college of wisconsin experience

Investigate the relationship between dosimetric parameters with local control (LC) and complications following transperineal high-dose rate (HDR) interstitial brachytherapy (ISBT) for gynecologic (GYN) malignancies. Between 2001 and 2016, 59 patients were treated for primary or recurrent GYN malignancies. Most patients received external beam irradiation, followed by transperineal ISBT via the Syed-Neblett applicator set with CT-based planning. Treatment plans were retrospectively reviewed to evaluate for an association among LC or toxicity with the equivalent dose at 2 Gy per fraction (EQD2) for the clinical target volume (CTV), 0.1 cc (D0.1cc), and 2 cc (D2cc) volumes of the organs at risk (OAR), low/high dose volumes for the OAR and CTV, and ratio of dose at the core vs. the implant periphery. The median follow-up among survivors was 24 months. 34% of patients had a component of local failure and in 12%, this was isolated. Late grade 3 (G3) toxicity occurred in 15% of patients. There were no G4-5 toxicities. Rectal D0.1cc > 75 Gy trended toward significance in predicting the development of non-fistula late G2-3 rectal complications. Bladder D0.1cc > 94 Gy significantly predicted for the development of late G2-3 vesicovaginal fistula formation. The ratio of the total dose at the vaginal surface to the needle periphery above 121% trended in predicting for any complication or fistula formation. HDR ISBT combined with EBRT achieved LC in 66% of patients with advanced or recurrent GYN cancers. Rectal and bladder D0.1cc doses may be predictive of complications as may the ratio of the implant dose at the core vs. periphery.

Dosimetric feasibility and clinical outcome of image guided interstitial brachytherapy using two different fractionation schedule in carcinoma cervix

Background: In advanced cervical cancer, external beam radiotherapy along with concurrent chemotherapy followed by brachytherapy is the treatment of choice. There are various dose fractionation regimes for template-based high dose rate (HDR) interstitial brachytherapy (ISBT) following external beam radiotherapy (EBRT) for cancer cervix with consideration of the normal-tissue EQD2 3Gy dose limits and recommended D90 goal between 85 and 95 Gy EQD2 10Gy for the high risk clinical target volume (HR-CTV). Materials and methods: 60 patients were accrued between 2014–2017 and treated with ISBT using Syed–Neblett Template by iridium 192 with Gamma Med plus HDR after loader unit. They were allotted in 2 arms (n = 30) and received 9 Gy ×2# and 7 Gy ×3 #, respectively. All patients received 50 Gy/25# whole pelvis EBRT by Theratron 780C. Coverage index (CI), dose homogeneity index (DHI), overdose index (OI), dose non-uniformity ratio (DNR), D90 Target and 2 cc EQD2 of OARs were calculated and correlated with toxicity, locoregional control and survival. Unpaired t-test and χ 2 test were used. Progression-free survival (PFS) and overall survival (OS) were calculated and a log-rank test was used for comparison. Results: Mean equivalent dose in 2 Gy fractions (EQD2) for the bladder (77.33 vs. 80.24 Gy) and rectum (69.12 vs. 69.87) along with D90 (9.12 Gy vs. 7.20 Gy) were comparable. With a median follow up period of 38 months, 3-year local control rate was 56.6% vs. 46.60% (p = 0.72) and 3-year OS was also similar: 83% vs. 80% (p = 0.8). Conclusions: In a developing country like India, 9 Gy ×2 # is a reasonably good alternative for treating locally advanced carcinoma cervix, keeping the patient compliance and convenience in mind.

Long term outcomes of Carcinoma Buccal Mucosa treated with High Dose Rate Interstitial Brachytherapy

To analyze the long-term local control, overall survival and toxicity in Carcinoma Buccal Mucosa patients treated with interstitial brachytherapy. This analysis included patients diagnosed as Carcinoma Buccal Mucosa on biopsy and treated with radical brachytherapy or External Beam Radiotherapy (EBRT) followed by brachytherapy boost. All patients received High dose rate (HDR) interstitial brachytherapy. The total dose was 35 Gy in ten fractions for brachytherapy alone. Patients who received EBRT (50-54 Gy) were boosted by brachytherapy to a dose of 18-24 Gy in 6-8 fractions. All patients were treated using CT based planning. Between 2007 to 2017, a total of 24 patients of Carcinoma Buccal Mucosa received HDR interstitial brachytherapy either alone or as a boost. Majority of the patients were tobacco chewers (80%). 17(71%) patients were clinical stage T2N0M0 and 7(29%) were clinically T1N0M0. At a median follow up of 7 years (3-12 years), the local control rate was 100% in stage I and 88% in stage II. The 5 year overall survival rate was 80%. Two patients developed nodal recurrence and one patient developed distant metastasis within two years of treatment. Tumor size and brachytherapy technique (radical vs. boost) did not impact local control or overall survival (p > 0.05). Majority of the acute toxicities were Grade 1 and 2. One patient developed osteoradionecrosis of the mandible. Interstitial brachytherapy in early-stage Buccal Mucosa cancer either alone or as a boost provides excellent long term local control and overall survival. The acute and late toxicities are acceptable with majority of the patients presenting with Grade 1 or 2 toxicity.

Computed Tomography-Based Interstitial Brachytherapy for Recurrent Cervical Carcinoma in the Vaginal Apex

AimsTo determine the factors influencing the outcomes of patients with recurrences post-hysterectomy for cervical cancers treated with external beam radiotherapy (EBRT) and interstitial brachytherapy. Materials and methodsThis prospective study accrued 90 patients between October 2008 and May 2014. All patients had had a prior hysterectomy and were diagnosed with recurrent vaginal apex cancers with squamous cell carcinomas. All underwent EBRT of 50 Gy (2 Gy/fraction) using tomotherapy-based image-guided intensity-modulated radiotherapy with concurrent chemotherapy of weekly cisplatin (40 mg/m2) followed by high dose rate interstitial brachytherapy boost of 20 Gy (4 Gy/fraction twice a day). Local relapse, disease-free and overall survival were determined. ResultsAt a median follow-up of 74 months (4–123 months), 10/90 (11%) patients had local failure as the first site of relapse and 12/90 (13.3%) had first distant relapse. Only one patient had synchronous local and distant relapse. The 7-year local relapse-free, disease-free and overall survival were 87.6, 68.3 and 68.3%, respectively. Grade 2 and 3 rectal toxicity were seen in 5.6 and 3.1% of patients, respectively. Among these, two (2.2%) patients underwent temporary diversion colostomy due to vaginal sigmoid and rectovaginal fistula. Grade 2 and 3 bladder toxicity were seen in 5.6 and 1.1% of patients, respectively. In summary, the lateral disease extent (P = 0.048) and the presence of nodal disease at diagnosis (P = 0.08) had a statistically significant or borderline impact on local relapse without any impact on disease-free survival. Tumour size in itself did not affect overall survival. ConclusionWith the integration of EBRT and interstitial brachytherapy, most vaginal apex recurrences can be salvaged. An excellent local control and survival is achievable using intensity-modulated radiotherapy with image guidance and concurrent chemotherapy followed by high dose rate interstitial brachytherapy.

The 3-Year Outcome of 3D High-Dose-Rate Brachytherapy in Combination With Regional Metastatic Lymph Nodes Intensity-Modulated Radiotherapy in Peripheral Locally Advanced Non-Small Cell Lung Cancer: A Phase I/II Clinical Trial

To determine the safety, late toxicities and locoregional control of three-dimensional(3D) high-dose-rate (HDR) brachytherapy in combination with regional metastatic lymph nodes intensity-modulated radiotherapy (IMRT) in patients with peripheral locally advanced non-small cell lung cancer (LA-NSCLC).Eligible patients with LA-NSCLC were recruited to this prospective, phase I/II clinical study. The primary lung tumors were treated with the CT-guided interstitial HDR brachytherapy, DT:30Gy/F. The IMRT was applied to the regional positive lymph nodes, DT: 60-70Gy/30-33F/ 6-7W. The concurrent chemotherapy regimens include used Etoposide and cisplatin, the sequential chemotherapy consisted of paclitaxel/pemetrexed + cisplatin/carboplatin. The safety analysis included operational complications and toxicity related to radiotherapy and chemotherapy. Clinical evaluation includes short-term efficacy, survival, and quality of life scores.A total of 83 patients were enrolled in this study. There were 56 males and 27 females, with a median age of 65 years (45-80 years). The median follow-up time was 55 months (32-114 months) up to November 2020. The operational complications included mild pneumothorax (16.8%) and minor hemorrhage around the needle (19.3%). The major toxicity was myelosuppression and gastrointestinal reaction during the concurrent chemoradiotherapy and sequential chemotherapy. The clinical symptoms alleviated after symptomatic supportive treatment. The radiotherapy was completed successfully without grade 4 or more serious acute toxicity. Grade 1 late radiation pneumonitis was found by in 5 patients (6.1%), and only showed imaging changes after radiotherapy. There were 61 patients achieved complete remission, 20 patients achieved partial remission, and 2 patients were in stable disease in the primary tumor, the total response rate was 97.6%. There were 55 patients achieved complete remission, 22 patients achieved partial remission, 5 patients were in stable disease and 1 patient with progressive disease in the positive lymph nodes, the total response rate was 92.8%. The 1-,2-,3-year overall survival rates were 90.6%, 70.6% and 62.4%. The 1-,2-,3-year local control rates were 90.0%,81.0% and 54.5%. The 1-,2-,3-year disease-free survival rates were 68.3%,42.2% and 23.9%. The 1-,2-,3-year metastasis-free survival rates were 73.3%, 50.9% and 39.5%. The patient who treated with 3D interstitial high dose rate brachytherapy has a higher life quality score than the baseline level.3D interstitial high dose rate brachytherapy combined with regional positive lymph node intensity-modulated radiotherapy is safe and feasible for the locally advanced peripheral non-small cell lung cancer, with low adverse reactions, increased the survival, and improved the life quality. But it still needs a phase III randomized controlled trial to investigate its clinical utility and promotion, compared to IMRT.

Radioablation of Upper Abdominal Malignancies by CT-Guided, Interstitial HDR Brachytherapy: A Multivariate Analysis of Catheter Placement Assisted by Ultrasound Imaging.

To evaluate the use of ultrasound (US) during catheter placement in interstitial brachytherapy (iBT) of abdominal malignancies as an alternative to computed tomography (CT) fluoroscopy. Catheter placement for CT-guided iBT was, if US visibility was sufficient, assisted by sonography in 52 consecutive patients with 82 lesions (liver N = 62; kidney N = 16; peritoneum N = 4) of various malignancies. We collected data on lesion visibility, location, depth, size, and dosimetry. Comparison of CT fluoroscopy versus US-assisted catheter placement was performed by Fisher's exact test for frequencies and U-test for lesion visibility and dosimetric data. Factors predicting the utility of sonography were determined in a lesion-based multivariate regression analysis. A p-value < 0.05 was regarded as statistically significant. 150 catheters (1 to 6 per lesion; mean diameter 3.6 ± 2.4 cm) were implanted. CT fluoroscopy was used for 44 catheters, and US was used for 106 catheters. Lesion visibility assessed by 5-point Likert scale was significantly better in US (median 2 vs. 3; p = 0.011) and effective dose was significantly reduced if US guidance was applicable (median 1.75 vs. 8.19 mSv; p = 0.014). In a multivariate regression analysis, we identified increased lesion size and caudal location within the target organ to independently predict the utility of ultrasound in catheter placement for iBT. Sonography is a helpful technique to assist CT-guided interstitial brachytherapy of upper abdominal malignancies. Especially for larger lesions localized in the lower liver segments or lower half of the kidney, superior visibility can be expected. As the effective dose of the patient is also reduced, radiation exposure of the medical staff may be indirectly lowered. · Ultrasound-assisted catheter placement in CT-guided brachytherapy of upper abdominal malignancies significantly improves lesion visibility.. · Predictors of successful ultrasound application are larger lesions within the lower portion of the liver and kidney.. · By reducing the need for CT fluoroscopy during intervention, radiation exposure to the medical staff may be indirectly lowered.. · Damm R, Damm R, Heinze C et al. Radioablation of Upper Abdominal Malignancies by CT-Guided, Interstitial HDR Brachytherapy: A Multivariate Analysis of Catheter Placement Assisted by Ultrasound Imaging. Fortschr Röntgenstr 2022; 194: 62 - 69.