Cervix Cancer Brachytherapy Research Articles

Integration of Ultrasound in Image-Guided Adaptive Brachytherapy in Cancer of the Uterine Cervix

Cervical cancer continues to be a public health concern, as it remains the second most common cancer despite screening programs. It is the third most common cause of cancer-related death for women, and the majority of cases happen in developing nations. The standard treatment for locally advanced cervical cancer involves the use of external beam radiation therapy, along with concurrent chemotherapy, followed by an image-guided adaptive brachytherapy (IGABT) boost. The five-year relative survival rate for European women diagnosed with cervical cancer was 62% between 2000 and 2007. Updated cervical cancer treatment guidelines based on IGABT have been developed by the Gynecological working group, which is composed of the Group Européen de Curiethérapie–European Society for Therapeutic Radiology and Oncology. The therapeutic strategy makes use of three-dimensional imaging, which can be tailored to the target volume and at-risk organs through the use of computed tomography or magnetic resonance imaging. Under anaesthesia, the brachytherapy implantation is carried out. Ultrasonography is utilised to assess the depth of the uterine cavity and to facilitate the dilation of the uterine canal during the application insertion. In this study, we examine data from the international literature regarding the application of ultrasound in cervical cancer brachytherapy.

Dosimetric and toxicity comparison between Syed-Neblett and Fletcher-Suit-Delclos Tandem and Ovoid applicators in high dose rate cervix cancer brachytherapy

PURPOSETo compare patient and tumor characteristics, dosimetry, and toxicities between interstitial Syed-Neblett and intracavitary Fletcher-Suit-Delclos Tandem and Ovoid (T&O) applicators in high dose rate (HDR) cervical cancer brachytherapy. METHODSA retrospective analysis was performed for cervical cancer patients treated with 3D-based HDR brachytherapy from 2011 to 2023 at a single institution. Dosimetric parameters for high-risk clinical target volume and organs at risk were obtained. Toxicities were evaluated using the Common Terminology Criteria for Adverse Events version 5.0. RESULTSA total of 115 and 58 patients underwent Syed and T&O brachytherapy, respectively. Patients treated with Syed brachytherapy were more likely to have larger tumors and FIGO stage III or IV disease. The median D2cc values to the bladder, small bowel, and sigmoid colon were significantly lower for Syed brachytherapy. Patients treated with Syed brachytherapy were significantly more likely to be free of acute gastrointestinal (44% vs. 21%, p = 0.003), genitourinary (58% vs. 36%, p = 0.01), and vaginal toxicities (60% vs. 33%, p = 0.001) within 6 months following treatment compared to patients treated with T&O applicators. In contrast, Syed brachytherapy patients were more likely to experience late gastrointestinal (68% vs. 49%, p = 0.082), genitourinary (51% vs. 35%, p = 0.196), and vaginal toxicities (70% vs. 57%, p = 0.264). CONCLUSIONSSyed-Neblett and T&O applicators are suitable for HDR brachytherapy for cervical cancer in distinct patient populations. Acute toxicities are more prevalent with T&O applicators, while patients treated with Syed-Neblett applicators are more likely to develop late toxicities.

PO31 Presentation Time: 10:30 AM: Dosimetric Evaluation of Normal Tissue Sparing in MRI Guided Adaptive Brachytherapy with Replan at Each Treatment Fraction in Cervix HDR Brachytherapy

<h3>Purpose</h3> Evaluate target and organ at risk (OAR) dosimetric benefit with replan at each treatment fraction in MRI guided adaptive brachytherapy (MRIGABT) for cervix cancer. <h3>Materials and Methods</h3> Radiotherapy treatment planning MRI (RTPMRI) were acquired before each brachytherapy fraction (1-4), in 10 patients treated with intrauterine brachytherapy (IUB) using the Venezia^TM applicator. Each patient had 2 IUB applicator insertions and received 28 Gy/4# following EBRT 25 Gy/25# (EMBRACE II protocol)¹. A replan based on anatomy on MRI acquired on day 2 (D2) of each IUB applicator insertion was planned and delivered (D2-replan). Total target and OAR dose was compared to conventional treatment where the treatment plan on day 1 of IUB applicator insertion is also delivered on day 2 (no replan). Total biologically equivalent doses for EBRT and brachytherapy were calculated in 2 Gy equivalents using the EQD2 equation and reported as total dose (Gy). <h3>Results</h3> Forty RTPMRI and IUB HDR treatment plans were analysed in 10 patients. The mean (±SD) total dose (EBRT + HRCTV 90) received for D2-replan and D2-no replan was 91.9 Gy (±2.3) and 90.5 Gy (±2.8). There was no statistically significant difference in target and OAR dose between D2-replan and no replan. But in individual patients there were clinically significant differences. No OAR dose constraints were exceeded with D2-replan, OAR dose constraints were exceeded in 5-20% of fractions when there was no replan (rectum 8/40#, sigmoid 2/40#, bowel 2/40# and bladder 2/40#). <h3>Conclusions</h3> Daily MRIGABT replan at each treatment fraction results in improved HRCTV dose and reduced OAR dose in some patients. With a replan, we saw consistent HRCTV D90 of >87 Gy, which is significantly associated with better disease control^2,3 especially in asymmetrical tumours. The additional resources required will not benefit all patients and selection criteria for patients who will benefit is required.

Friday, June 17, 20223:30 PM - 3:45 PMPO12: Time Investment and Planning Benefit of Serial Treatment Planning MRI Scans for HDR Intracavitary Brachytherapy for Cervix Cancer

<h3>Purpose</h3> To estimate the time investment and planning benefit of acquiring treatment planning MRI scans for each insertion for tandem and ring (T&R) cases. <h3>Materials and Methods</h3> Fourteen (14) consecutive cervical cancer patients who underwent intracavitary HDR brachytherapy with T&R applicator were retrospectively analyzed. All patients received 28Gy in 4 fractions delivered in 2 insertions (Ins1 and Ins2), with 2 fractions per insertion, after completion of EBRT. All insertions were performed under general anesthesia with intraoperative CT and MRI guidance. Target (Cx) and normal tissues were contoured on each MRI scan at the time of the procedure. Four patients who did not have both insertions using MRI planning were excluded. Image registration of Ins2 to Ins1 was retrospectively performed in Eclipse (Varian Medical Systems, Palo Alto, CA) based on applicator position. Target contour from Ins2 (Cx2) was copied to the Ins1 structure set (Cx2reg) using this registration. The following metrics were recorded: volume of Cx1, Cx2, and dice similarity coefficient of the two [DSC = 2*(volCx1+volCx2)/(overlap between Cx1 and Cx2reg)] (0 indicates no overlap between the contours; 1 indicates perfect overlap). Target D90 using MRI for each insertion (D90 Cx1 on plan of Ins1 + D90 Cx2 on plan of Ins2) and using only Ins1 MRI (D90 Cx1 on plan of Ins1 + D90 Cx2reg on plan of Ins1). One patient had a replan for the second fraction of the first insertion was therefore excluded from the D90 analysis. Additional time required for MRI-based planning was calculated using the timestamps of the last in-room CT and of the T2 MRI. <h3>Results</h3> Cx1 and Cx2 volumes [median, interquartile range (IQR)] were 26.0 cm³ (IQR 11.3 cm³) and 22.9 cm³(IQR 16.7 cm³). DSC was 0.73 (IQR 0.05). Target D90 (as % of prescription dose) using MRI for each insertion vs. using only Ins1 MRI information for Ins2 was 109.6% (IQR 4.8%) vs. 110.1% (IQR 7.5%). Additional time for MRI-based planning was 38.8 minutes (IQR 6.3 minutes). <h3>Conclusions</h3> The addition of an MRI for Ins2 added only modest alterations in the target volume and D90, however, did add approximately 40 minutes of added time under anesthesia. The projected target coverage if Cx1 was used in insertion 2 instead of Cx2 would be sufficient and could be more efficient in terms of scan and, potentially, contouring time. This study supports the hypothesis that the time commitment required for MRI acquisition for Ins2 may not be justified by a planning advantage. Limiting factors of this study: contouring and fusion uncertainties; our methods did not consider changes in organs-at-risk between insertions; limited number of patients.

Applying 3D-Printed Templates in High-Dose-Rate Brachytherapy for Cervix Cancer: Simplified Needle Insertion for Optimized Dosimetry

In cervical cancer brachytherapy, adding interstitial needles to intracavitary applicators can enhance dosimetry by improving target coverage while limiting normal tissue dose. However, its use is limited to a subset of practitioners with appropriate technical skill. We designed tandem anchored radially guiding interstitial templates (TARGITs) with a 3-dimensional (3D) printing workflow to optimize needle placement and facilitate greater ease-of-use of intracavitary/interstitial (IC/IS) technique. This study compared dosimetry and procedure characteristics between tandem and ovoid (T&O) implants using TARGIT technique versus non-TARGIT technique. This single-institution retrospective cohort study included patients undergoing T&O brachytherapy as part of definitive radiation treatment for cervical cancer between February 2017 and January 2021. TARGIT technique was implemented from November 2019 onwards; all prior procedures involved non-TARGIT technique using a no needle or freehand needle approach. Target coverage, dose to organs at risk, and procedure times were evaluated and compared between TARGIT technique and non-TARGIT technique. The cohort included 70 patients with cervical cancer who underwent 302 T&O procedures: 68 (23%) with TARGIT technique and 234 (77%) with non-TARGIT technique, which included 133 no needle and 101 freehand needle implants. TARGIT implants involved longer average procedure times (+6.3 minutes, P < .0001). TARGIT implants achieved a higher mean high-risk clinical target volume V100% than non-TARGIT implants (+4.4%, P = .001), including for large tumors 30 cm3 or greater (+8.1%, P = .002). Average D90 was 4.6 Gy higher and average D98 was 3.2 Gy higher for TARGIT technique compared with non-TARGIT technique (P = .006 and P = .02). Total treatment doses to rectum, bowel, and bladder were not significantly different for TARGIT versus non-TARGIT technique. The 3D-printed TARGIT approach to T&O brachytherapy achieved greater tumor coverage while sparing normal tissues, particularly for large tumor volumes, with only a slight increase in average procedure time. TARGIT represents a creative technological solution for increasing accessibility of advanced IC/IS brachytherapy technique for cervical cancer definitive radiation treatment.

Feasibility of electronic brachytherapy in cervix cancer–A dosimetric comparison of different brachytherapy techniques

This study analyzes cases in which electronic brachytherapy (eBT) led to acceptable treatment plans in cervical cancer. Findings were compared with dosimetry values obtained in 192Ir-based treatments according to the high-risk clinical target volume (HR-CTV) and the disease stage. We retrospectively analyzed 48 patients with cervical cancer from two centers. The patients were treated with 192Ir based on MRI. It was possible to use interstitial needles via an Utrecht-type applicator. Dosimetry was simulated using eBT and the parameters D90 and D98 (HR-CTV) and D2cc, D1cc, and D0.1cc (bladder, rectum, and sigmoid colon) were evaluated. The Mann-Whitney U test was used for comparison. The overall cohort of patients was analyzed, as were the sub-cohorts based on stage (FIGO stages I+IIA, IIB and III-IV). Finally, the dosimetry of the eBT plans was evaluated, and the plans obtained were classified as "good", "acceptable", or "poor". Statistically significant differences were found between the eBT and 192Ir plans for D98 (HR-CTV), D1cc and D0.1cc (bladder), and D1cc and D0.1cc (sigmoid colon). A total of 31 cases (64.6%) were considered good, seven (14.6%) were considered acceptable, and 10 (20.8%) were considered poor. For volumes <30 cc, all the plans were good or acceptable; for volumes >30 cc, 54.3% were good, and 71.4% were good or acceptable. By stage, eBT plans for patients with stage IB-IIA disease were good in 100%, whereas those for patients with stage IIB were good in 70.6% and III-IV disease were good in 50%. eBT provides appropriate dosimetry for treatment of cervical cancer in selected cases.

Dose Prediction for Cervical Cancer Brachytherapy Using 3-D Deep Convolutional Neural Network

Brachytherapy is a critical modality in treatment of cervix cancer. However, developing a clinically acceptable plan is a time-consuming manual process. In this article, we propose a dose prediction method for cervix cancer brachytherapy using a 3-D deep convolutional neural network (CNN) to guide treatment planning. The method learns the prediction model from a database of historical treatment plans and predicts the 3-D dose distribution with the 3-D organ structures and positions of the inserted applicators as inputs. 110 treatment plans for cervical cancer brachytherapy were used for training the deep CNN to learn a 3-D dose prediction model. Twenty cases were used to evaluate the performance of the proposed method by analyzing the outcomes in terms of mean dose values, derived DVHs from dose distribution, and statistical analysis of sum of absolute residual. Our results show that the predicted mean V100 of the CTV and mean D2cc of organ-at-risks are close to those in the clinical treatment plans. The mean D2cc doses in bladder, rectum and bowel are 5.97, 3.67, and 4.05 Gy, respectively, in comparison to 5.77, 3.42, and 4.16 Gy in clinical plans, indicating a great potential to predict accurate dose distribution and facilitate the brachytherapy treatment planning workflow.

The Fusion of MRI and CT in the Planning of Brachytherapy for Cancer of the Uterine Cervix

Introduction: tumors of the uterine cervix are among the most common carcinomas in women. Intracervical brachytherapy is an indispensable part of curative treatment. Although the tumor is significantly more recognizable in MRI than in CT, the practical application of MRI in brachytherapy planning is still difficult. The present study examines the technical possibilities of merging CT and MRI. Materials and Methods: the treatment files and imaging of all 53 patients who had been irradiated by image-guided adaptive brachytherapy (IGABT) between January 2019 and August 2021 at the Department of Radiotherapy of the Hannover Medical School were evaluated, retrospectively. Patients were treated first with an external beam radiotherapy (EBRT) combined with simultaneous chemotherapy. After an average of 4.2 weeks, the preparation for IGABT began. The clinical target volume (CTV) for brachytherapy was contoured first in an MRI acquired before starting EBRT (MRI 1) and once more in a second MRI just before starting IGABT (MRI 2). Then, after inserting the intravaginal applicator, a CT-scan was acquired, and the CTV was contoured in the CT. Finally, the recordings of MRI 1, MRI 2, and the CT were merged, and the congruence of CTVs was quantitatively evaluated. Results: the CTV delineated in MRI 2 was, on average, 28% smaller than that in MRI 1 after an average applied radiation dose of 42 Gy. The CTV delineated in the CT covered an average of no more than 80.8% of the CTV delineated in MRI 2. The congruence of CTVs was not superior in patients with a smit sleeve in the cervical channel, with a 3D-volumetric MRI or with a contrast-enhanced sequence for MRI. Conclusion: the anatomical shape and position of the uterus is significantly changed by introducing a vaginal applicator. Despite the superior delimitability of the tumor in MRI, brachytherapy cannot be reliably planned by the image fusion of an MRI without a vaginal applicator.

Comparison of vaginal gauze packing technique with or without balloon in high-dose-rate brachytherapy of uterine cervical cancer: A crossover randomized controlled trial.

To compare the rectal and bladder doses using two different vaginal packing techniques among uterine cervical cancer patients receiving high-dose-rate (HDR) intracavitary brachytherapy (ICBT). Forty-five patients with cervical cancer were randomized to receive two sessions of ICBT using tandem and ring applicator (Varian©), following completion of pelvic external beam radiotherapy treatment. The procedure was performed with vaginal balloon plus gauze packing or vaginal gauze packing alone, each of which was used in one of two sessions. Sequence of the type of vaginal packing was chosen with computer-generated block randomization. A HDR dose of 8.5 Gy was prescribed to point A in all patients. Volumetric dose parameters, such as D0.1cc, D0.5cc, D1cc, and D2cc of the rectum and bladder were compared between the two techniques of vaginal packing. The mean age of patients was 51 years. Majority (88%) of patients had locally advanced stages of cancer at baseline (stage IIB or more). Rectal doses were significantly less in combined packing technique (D0.1cc: 7.52 Gy vs. 9.02 Gy, p = 0.01; D0.5cc: 6.46 Gy vs. 7.42 Gy, p < 0.01; D1cc: 5.91 Gy vs. 6.7 Gy, p < 0.01; D2cc: 5.29 Gy vs. 5.97 Gy, p < 0.01). Bladder doses were higher in the combined packing technique (D0.1cc: 11.20 Gy vs. 10.76 Gy, p = 0.18; D0.5cc: 9.64 Gy vs. 9.32 Gy, p = 0.56; D1cc: 8.64 Gy vs. 8.36 Gy, p = 0.55; D2cc: 7.56 vs. 7.33 Gy, p = 0.55). Combined vaginal packing resulted in statistically significant reduction in rectal radiation dose compared with standard vaginal gauze packing in high-dose-rate brachytherapy of cervix cancer using tandem and ring applicators.

Commissioning and Dosimetric Results of an Indigenously Developed Intra-Vaginal Template for Interstitial Plus Intracavitary High dose Rate Image-Guided Brachytherapy of Advanced Cervix Cancer.

The goal of this study is to discuss the commissioning and dosimetric parameters achieved during the clinical implementation of an indigenously developed intracavitary (IC) plus interstitial (IS) template for high dose rate (HDR) image-guided brachytherapy (IGBT) in cancer (Ca) cervix. We want to discuss our achieved values of cumulative equi-effective doses (EQD2) for high-risk clinical target volume (HRCTV) and organ at risk (OAR) and compare it with available published results. Medanta anterior oblique/lateral oblique template has a total of 19 needles including the central tandem. For commissioning the template with needles, the indigenously made acrylic phantom was used. Oblique and straight needles were placed inside the acrylic phantom and a computed tomography (CT) scan was performed. Sixteen patients were treated in HDR IGBT using this template after external-beam radiotherapy. The IGBT plans were evaluated based on EQD2 of target coverage i.e., dose received by 98% (D98%_HRCTV), 90% (D90%_HRCTV), and 50% (D50%_HRCTV) volume of HRCTV, and dose received by 2 cc (D2cc) and 0.1 cc (D0.1cc) of OAR using linear quadratic (LQ) radiobiological model. The autoradiographic in radiochromic film shows that the distance between the needle tip and the middle of the source position is 6 mm. The mean D98%_HRCTV and D90%_HRCTV was 76.8 Gy (range: 70-87.7 Gy, P < 0.01) and 84.49 Gy (range: 76.6-96.7 Gy, P < 0.01), respectively. Mean EQD2 of D2cc of the bladder, rectum, and sigmoid was 85.6 Gy (range: 77.5-99.6 Gy, P < 0.03), 74.3 Gy (range: 70.9-76.7 Gy, P < 0.05), and 58.3 Gy (range: 50.6-67.9 Gy, P = 0.01), respectively. The mean total reference air kerma at a 1 m distance is 0.489cGy (range: 0.391-0.681cGy). The indigenously developed template could attain satisfactory standards in terms of set parameters for commissioning and acceptable dose volume relations in our clinical use for treating the advanced Ca cervix patients who need IC + IS type of HDR IGBT. The comparative analysis with contemporary applicators was acceptable.

The Relationship Between Late Morbidity and Dose-Volume Parameter of Rectum in Combined Intracavitary/Interstitial Cervix Cancer Brachytherapy: A Mono-Institutional Experience.

PurposeTo establish a dose volume–effect relationship for predicting late rectal complication (LRC) in locally advanced cervical cancer patients treated with external beam radiotherapy (EBRT) followed by combined intracavitary/interstitial brachytherapy (IC/IS-BT).Materials and MethodsA retrospective analysis was performed in 110 patients with locally advanced cervical cancer who underwent definitive radiotherapy combined with IC/IS-BT from July 2010 to September 2018. We report the 90% of the target volume receiving the minimum dose for high risk clinical target volume (HR-CTV D90) and intermediate risk clinical target volume (IR-CTV D90), and the minimum doses to the most exposed 0.1, 1, and 2 cm³ doses at the International Commission on Radiation Units and Measurements (DICRU) for organs at risk (OARs). The total dose of EBRT plus brachytherapy was transformed to the biologically equivalent dose in 2 Gy fractions (EQD2) with α/β value of 10 Gy for target, 3 Gy for organs at risk using the linear quadratic model. The morbidity was scored according to the Radiation Therapy Oncology Group (RTOG) criteria. The Probit model was used to establish a prediction model on rectum between the organs at risk for dose and LRC. The receiver operating characteristic (ROC) curve was used to evaluate the predictive value of dose volume parameters for LRC.ResultsThe median follow-up time was 72.3 months. The mean ( ± standard deviation) , and DICRU values of rectum were 64.72 ± 7.47 GyEQD2, 70.18 ± 5.92 GyEQD2, 79.32 ± 7.86 GyEQD2, and 67.22 ± 7.87 GyEQD2, respectively. The Probit model showed significant relationships between , and the probability of grade1–4, grade 2–4 rectal events at 1 year, and between and the probability of grade2–4 rectal events at 3 and 5 years. The dose values for 10% complication rates (ED10) of were 74.18 (70.42–76.71) GyEQD2, 67.80 (59.91, 71.08) GyEQD2, 66.37 (52.00, 70.27) GyEQD2 for grade 2–4 with rectal morbidity at 1, 3, and 5 years, respectively.ConclusionOur study proved that were considered as useful dosimetric parameters for predicting the risk of grade1–4 and grade2–4 LRC at 1-year, and might be an indicator for predicting grade2-4 LRC at 3/5years. The patients with rectal >66.37–74.18 GyEQD2 should be closely observed for grade2–4 LRC.

PP02 Presentation Time: 10:10 AM: 3D-Printing in Radiation Oncology: Development and Validation of Custom 3D-Printed Brachytherapy Alignment Device and Phantom

Purpose: 3D-printing has emerged as a promising tool for brachytherapy simulation, training, and research. In brachytherapy for cervix cancer, many patients have tumors or anatomy that do not conform to a standard blocking template for needle alignment. In this pilot study, we sought to create a 3D-printed device that provided customized needle alignment for a patient and developed a 3D-printed mold and anatomical “phantom” model based on a patient CT scan to test the device.

GSOR09 Presentation Time: 3:10 PM: Case Report and Literature Review on Ultrasound - MRI Hybrid Adaptive External Beam Radiotherapy and Brachytherapy for Cervical Cancer Patients

Purpose: Existing studies confirmed role of ultrasound to guide applicator insertion in cervix cancer brachytherapy. This study introduces important role in ultrasound features and serial changes combining with MR Adaptive radiotherapy and MR guided brachytherapy.

PO-0228 Inverse versus forward optimisation methods in brachytherapy of breast, cervix and prostate cancer

PO-0228 Inverse versus forward optimisation methods in brachytherapy of breast, cervix and prostate cancer

Ultrasound-guided Brachytherapy for Cervix Cancer

Radiotherapy and brachytherapy are the definitive treatments for locally advanced cervix cancer. The use of soft-tissue imaging, particularly magnetic resonance imaging, has enhanced their effectiveness and improved clinical outcomes. However, the use of magnetic resonance imaging is largely restricted to well-resourced centres in both the first and developing world and remains elusive to many less advantaged centres, particularly those in areas with a high burden of cervix cancer. Ultrasound is an accessible, affordable and accurate imaging modality that can be used throughout the brachytherapy procedure. Ultrasound is primarily used to ensure safe insertion of the applicator but can also be used to guide planning. The methods used to utilise ultrasound images for planning are described. Ultrasound is particularly useful as a verification aid to confirm applicator placement after patients are moved and transferred around the radiotherapy department. It can also be used to verify the dimensions of treatment volumes over the course of brachytherapy. There is a crucial unmet need for an accessible economical soft-tissue imaging modality in cervical brachytherapy. Ultrasound has the potential to meet this need.

Comparison of clinical outcomes achieved with image-guided adaptive brachytherapy for cervix cancer using CT or transabdominal ultrasound

PurposeThis study aimed to evaluate retrospectively the treatment results when using various image-guided adaptive brachytherapy treatments for cervical cancer treated by radical radiotherapy. Methods and MaterialsFrom 2014 to 2017, 188 patients with cervical carcinoma were treated by whole pelvic radiotherapy plus four fractions of image-guided brachytherapy. Eight patients were excluded because of missing data. Consequently, 180 patients were analyzed. Of 180 patients, 92 were treated by CT-based brachytherapy (CT-BT), and transabdominal ultrasound–based brachytherapy (TAUS-BT) was used to treat another group. The treatment results and toxicity outcomes were evaluated by comparing the image-guidance techniques. ResultsThe mean follow-up time was 32 months (interquartile range 29.5–42 months). The mean age was 57 years (interquartile range from 50 to 65 years). In the CT-BT group, the mean cumulative doses to high-risk clinical target volume, bladder, rectum, and sigmoid were 87.2 Gy, 84.0 Gy, 68.8 Gy, and 69.8 Gy, respectively. In the TAUS-BT group, the mean cumulative doses to the cervix reference, bladder, and rectum points were 84.0 Gy, 65.5 Gy, and 74.0 Gy, respectively. There were no differences in the 2-year local control rate (p = 0.88) and disease-free survival rate (p = 0.34) in both groups. No difference in gastrointestinal and genitourinary toxicity was observed in both groups, but there was higher vaginal toxicity in the TAUS-BT group compared with the CT-BT group (p = 0.03). ConclusionsNo difference in treatment results was observed between CT-based and TAUS-based approaches. However, TAUS-BT had higher vaginal toxicity in our retrospective analysis.

Non-anesthetist-administered moderate sedation with midazolam and fentanyl for outpatient MRI-aided hybrid intracavitary and interstitial brachytherapy in cervix cancer: a single-institution experience.

PurposeThe aim of the study was to determine the feasibility of interstitial brachytherapy under non-anesthetist-administered moderate sedation, to identify factors influencing the insertion, and the total procedural time.Material and methodsA total of 47 insertions with hybrid intracavitary and interstitial applicators were performed in 23 patients from March 2017 to March 2020. Moderate sedation was achieved with intravenous midazolam and fentanyl administered by non-anesthetist. Insertion time and procedural time was recorded. Univariate and multivariate analysis were performed to evaluate the impact of different factors on insertion and procedural time.ResultsA total of 238 needles (range, 2-8 per insertion) were implanted, with an average insertion depth of 30 mm (range, 20-40 mm). The mean doses for midazolam and fentanyl were 3 mg (standard deviation [SD] = 1) and 53.3 mcg (SD = 23.9) per insertion, respectively. The median insertion time was 30 minutes (interquartile range [IQR] = 22-40), and the median total procedural time was 4.3 hours (IQR = 3.6-5.2). First time insertion, insertions performed before 2019, and higher midazolam dose were associated with significantly longer insertion time, whereas longer insertion time, MRI-based planning, and insertions performed before 2019 were associated with significantly longer total procedural time.ConclusionsOutpatient interstitial brachytherapy with non-anesthetist-administered sedation is achievable and well-tolerated. This method may significantly lessen the burden on hospital resources and has the potential to be cost-effective.

Conventional vs. Volumetric Brachytherapy in the Treatment of Cervix Cancer: A Meta-Analysis of 30 Clinical Studies.

To ascertain if there is a difference in local control (LC) and disease-free survival (DFS) between conventional, point A-based brachytherapy (2D) and volume-based brachytherapy (3D) for cervix cancer and to determine which technique demonstrates superior patient outcomes in the form of a meta-analysis. We conducted a meta-analysis seeking 3-year clinical cohort data from prospective and retrospective studies to assess the effects of 2D and 3D brachytherapy. The search criteria included MeSH terms of “cervical neoplasms”, “brachytherapy”, “retrospective studies”, “disease free survival” along with the following terms: “high-dose-rate brachytherapy”, “survival analysis” and “local control”. This electronic search, as well as a search through reference sections of suitable studies yielded a total of 5145 studies. From these, 317 relevant full-text articles were screened and assessed for eligibility. Risk of bias was assessed by 2 separate reviewers through the CASP cohort study checklist and a personalized checklist assessing appropriateness of cervical carcinoma treatment. A final number of 30 studies were found to be relevant and met the quality criteria to be included for analysis. Patients included were from stages IB2-IVB, treated from 1995. in the 30 clinical studies. Treatment included concomitant chemo-radiotherapy and high-dose rate (HDR) brachytherapy (either 2D or 3D). Minimum follow-up was 2 years and outcomes were reported at 3 years. Weighted averages of aggregated (all stages combined) local control (LC) and disease-free survival (DFS) were calculated. Confidence intervals for the average weighted means and forest plots for the same were calculated. From a total of 30 studies, 5406 patients that presented 3-year aggregated LC and DFS, we found significant differences between 2D and 3D brachytherapy. Regarding 3-year aggregated LC, 27 studies (5821 patients) reported this outcome. The baseline LC for this entire cohort was 88.6%. According to brachytherapy type, 2D brachytherapy showed a LC of 86% (95% CI 83% – 89%) and 3D brachytherapy 92% (95% CI 90% - 93%). This 6% difference was statistically significant (p = 0.0005). With reference to DFS, 22 studies (4563 patients) reported this outcome. The baseline 3y DFS for the cohort was 73.4%. According to brachytherapy type, 2D brachytherapy showed a DFS of 69% (95% CI 64 – 74%) and 3D brachytherapy was associated with 3 yr DFS of 75% (95% CI 72 - 78) for patients treated with 3D brachytherapy. This 6% improvements in LC and DFS were statistically significant (p = 0.0005, p = 0.03). Volumetric-based (3D) brachytherapy as treatment for cervical carcinoma patients results in superior 3-year LC and DFS relative to point A based (2D) brachytherapy. These results can be translated into population impact and can inform policymakers to upgrade national radiotherapy practices. It can also be used as a starting point for clinical trials to explore long-term clinical outcomes.

Education and training for image-guided adaptive brachytherapy for cervix cancer—The (GEC)-ESTRO/EMBRACE perspective

Image-guided adaptive brachytherapy (IGABT) has been shown to improve local/regional control and survival for cervix cancer patients while reducing morbidity. However, the technique is complex involving several conceptual, methodological, and technical innovations compared to conventional brachytherapy. The delivery of high-quality IGABT which will translate into improved outcomes is therefore critically dependent on effective education and training of all health professionals involved in the brachytherapy treatment process. This paper reviews the (GEC)-ESTRO/EMBRACE initiatives for education and training to promote the dissemination and implementation of IGABT for cervix cancer worldwide. The new skills required in different health professionals for successful implementation of IGABT are described. The achievements and challenges of current educational strategies for disseminating IGABT are discussed. Innovations to improve the effectiveness of current and future educational strategies are explored.

Accuracy of Intracavitary Applicator Reconstruction for Cervix Cancer Brachytherapy

The accuracy of intracavitary applicator reconstruction for cervical cancer was assessed. A homemade phantom that mimics clinical applicator placement and reference points was used. Three stainless steel (15°, 30°, and 45°) tandems, x-ray markers, and three reference points were used to compare radiography- and CT-based systems. For CT reconstructions, two Fletcher CT compatible (15° and 30°) tandems, two ovoids, and two reference points, with and without inserted x-ray markers, were used. A 2.5-mm CT slice thickness was used. To check for inter- and intra-operator variations in CT, only a 30° tandem without x-ray markers and 1.25-mm CT slice thickness were used. Applicators were reconstructed three times for each image set to verify the operator reproducibility. A 6 Gy dose was prescribed and normalized at AL-point. Source dwell times were compared to check for dose variation at A-point. Maximum standard deviations SD (σ) for radiography and CT reconstructions were 0.35 and 0.83 mm, respectively. Analysis of variance for the means of 15° and 30° tandems showed no significant difference. Levene’s test proved insignificant difference for 15° tandem (p value = 0.131), whereas it showed a significant difference for 30° tandem (p value = 0.011). This phantom study showed that the variance of dwell times between the two methods for 30° tandem was statistically significant due to increased applicator curvature. CT proves superiority to radiography. X-ray marker method was more accurate but has less image quality. Inter- and intra-oncologist variations showed good agreement.