To compare radiation doses achieved by image-guided brachytherapy for locally advanced cervical carcinoma implemented with two different protocols.
Medical records of 117 patients with locally ...advanced cervical carcinoma treated with brachytherapy from 2009 to 2018 at our institution were retrospectively reviewed. All patients had received previous external beam radio/chemotherapy. We performed magnetic resonance image-guided adaptive high-dose-rate brachytherapy delivered by intra-cavitary/interstitial applicators. Dose prescription was 7 Gy for four fractions within two weeks. Original schedule of brachytherapy was two fractions delivered on consecutive days with one applicator insertion; this process was repeated one week later (group 1, 54 patients). From 2015 onwards, another protocol of brachytherapy was mainly used, separately performing applicator insertions for each of the four administered fractions (group 2, 63 patients).
The high-risk clinical target volume (HR-CTV) D
planning aim (PA) of ≥ 85 Gy (hard constraint) was not achieved in 9 cases out of 54 (17%) in group 1 compared with only 2 out of 63 cases (3%) in group 2 (
= 0.022). A difference between the two groups was also found in the fulfillment of PA 90 Gy (soft constraint) (
= 0.027). We conducted a sub-group analysis of target volume groups and observed that the differences were most pronounced with very large tumors (> 50 cm
). In these patients, PA 85 Gy was only fulfilled in 67% cases when treatment involved two applications, but in all cases with four separate applicator insertions (
= 0.010).
In our experience, by performing an applicator insertion for each of the fractions, it is possible to correct the non-optimal position of the applicator immediately, and to deliver better doses for consecutive fractions. As a result, the planning aim is more often achieved, especially for large tumors.
To evaluate treatment results and investigate predictors of local control.
In this retrospective study of 236 patients with cervical cancer, we administered CT-based adaptive brachytherapy (BT) in ...combination with whole- pelvic (WP)- and central shielding (CS)- external beam radiotherapy (EBRT) with or without chemotherapy. The study cohort comprised patients with cervical cancer treated with definitive radiotherapy (RT) or concurrent chemoradiotherapy between June 2013 and March 2019. Local control (LC), overall survival (OS), and late toxicity were evaluated. Predictive factors for LC were analyzed by univariate and multivariate analyses.
Median doses of WP- and CS-EBRT and BT were 30.6 GyEQD2, 19.8 GyEQD2, and 40.3 GyEQD2, respectively. The 3-year LC rates for T1b2, T2a, T2b, T3b, and T4 were 100%, 100%, 97.3%, 86.9%, and 91.7%, respectively (p = 0.346). The 3-year OS for Stages IB, IIB, IIIB, IIIC, and IVA were 100%, 94.8%, 82.5%, 81.7%, and 74.6%, respectively (p = 0.037). Rates of Grade 3–4 gastrointestinal and genitourinary toxicities were 3.8% and 1.7%, respectively. Multivariate analysis showed that T3–4, nonsquamous cell histology, and high-risk clinical target volume (CTVHR) D90 of BT < 36GyEQD2 were independently associated with significantly poorer LC.
The combination of WP- and CS-EBRT and CT-based IGBT with or without concurrent chemotherapy produced favorable LC outcomes with low rates of late toxicities for patients with small or medium-sized tumors. However, LC was less favorable for patients who had large T3 disease, and the use of CS requires caution in these patients.
Brachytherapy (BT) for cervix cancer was listed as a level I priority and reduced number of implants and multiple fractions were recommended during COVID-19 pandemic. We present early clinical ...outcome of this approach.
Patients treated with (chemo)radiotherapy and BT with single implant and multiple fractions BT were included. Treatment protocol included 3-5 fractions of 5-8.5 Gy with an aim to achieve point A dose of 70 Gy EQD2
(or HRCTV dose of >80 Gy EQD2
) in those undergoing intracavitary (IC) and HRCTV dose >85 Gy EQD2 10Gy in patients undergoing Intracavitary-Interstitial (IC/IS) whereas maintaining bladder (B2cc), rectum (R2cc), sigmoid (S 2cc) doses of 90, 75, and 75 Gy EQD2
. Time to event analysis was used to report oncological endpoints. Toxicity was reported using crude proportions.
From April 2020 to March, 2021, 64 patients with stage IB2-IV received single implant and multi-fraction BT after external radiation of 45 Gy/25 fractions/5 weeks. Only 76.7% (n = 49) received concurrent chemotherapy. Median overall treatment time (OTT) was 56 days (38-131 days). Overall, 62.5% (n = 40) patients received IC and 37.5% (n = 24) received IC+IS. The median HRCTV was 34.7 cc (IQR 25-41). Median (IQR) point A dose, HRCTV D90, B2cc, R2cc, and S2cc for those undergoing IC was 74 Gy (71-78), 80 Gy (73-84), 86 Gy (82-89), 70 Gy (65-74), 65 Gy (59-73) respectively. For the IC+IS cohort, HRCTV D90, B2cc, R2cc, and S2cc was 84 Gy (78-89 Gy), 89 Gy (86-92), 70 Gy (67-74), 68 Gy (59-76). At a median follow-up of 16 months (5-27) the 2-year local control, pelvic control, cause specific and overall survival was 88%, 85.3%, 92.2%, and 81.3% respectively. Late gastrointestinal and genitourinary grade ≥III toxicities were 14% and 1.5% each.
Abbreviated BT outcomes are encouraging for oncological outcomes despite delays in overall treatment time and omission of chemotherapy. Further mature follow up is needed.
To provide educational support to brachytherapy users during the COVID-19 pandemic, online workshops were developed and implemented by BrachyAcademy, non-profit peer-to-peer educational initiative in ...Elekta.
In 2021–2022 two online workshops were organized. Participating teams had to send a clinical case of locally advanced cervical cancer (LACC) including brachytherapy Digital Imaging and Communications in Medicine (DICOM) files and questions to the faculty. During the workshop, feedback was given to each clinical case by five faculty members (two Radiation Oncologists, one Radiologist, two Medical Physicists). Participants competed a post-workshop questionnaire which included combination of qualitative and quantitative questions via yes/no responses, Likert scale, and 1 to 10 scale.
Twenty-one teams from eight countries (Europe, Asia, Latin America) participated in two online workshops. The total number of participants was 49. The clinical cases represented LACC with The International Federation of Gynecology and Obstetrics (FIGO) stages from IB3 to IVA. During both, Workshop1 (W1) and Workshop 2 (W2) the following areas of improvement were identified: familiarity with the GEC ESTRO and The International Commission on Radiation Units & Measurements, Report 89 (ICRU 89) recommendations for contouring and planning based on clinical drawings and MRI sequencing choice; appropriate applicator selection; experience with interstitial needles; appropriate applicator reconstruction; dose optimization. The participants rated both workshops with overall scores 8,3 for W1, and 8,5 for W2. In 82% participants the training course fully met expectations for W1, and in 76% in W2.
We successfully implemented the online workshops on image-guided adaptive brachytherapy (IGABT) in LACC. Main performance issues and areas for improvement were identified based on multidisciplinary discussion of participant's clinical cases through all steps of the brachytherapy procedure. We encourage teams to consider online workshops in addition to hands-on training.
•Many women are unable to undergo standard surgical staging for endometrial cancer.•Women with low-volume disease were treated with 3D-image guided brachytherapy alone.•Two-year overall and ...cancer-specific survival rates were 90% and 97%, respectively.•No grade 3+ acute or late toxicity was observed.•Brachytherapy is an alternative approach in low-volume disease inoperable women.
Management of endometrial cancer consists of surgical staging with adjuvant therapy guided by risk factors, though some women cannot undergo surgery due to comorbidities. We present a series of women treated with definitive high-dose rate image-guided tandem and cylinder brachytherapy (HDR-IGBT) alone.
Patients with grade 1–2, clinical stage I endometrial adenocarcinoma, <50% myometrial invasion, and tumor≤2cm were reviewed. Definitive treatment consisted of 5–6 fractions HDR-IGBT alone with CT- or MRI-based planning. Local-regional control (LRC) was defined as complete imaging response and/or cessation of vaginal bleeding.
From 2007 to 2016, 45 patients were treated to a median dose of 37.5Gy. The median gross tumor volume (GTV) and clinical target volume (CTV) were 5.9cm3 (range, 0.7–18.7) and 80.9cm3 (17.2–159.0), respectively. The median cumulative dose to 90% (D90) of the GTV was 132.8Gy (76.5–295.6) equivalent 2Gy dose, and the median CTV D90 was 49.7Gy (34.5–57.2). Median follow-up among living patients was 18.6months (3.0–64.3). Cessation of vaginal bleeding occurred in 98%. Among those with post-treatment MRI (64%), complete radiographic response was demonstrated in 90%. The 2-year LRC, cancer-specific survival, and overall survival rates were 90%, 86%, and 97%, respectively. No grade 3+ acute or late toxicity was observed.
HDR-IGBT alone for treatment of early-stage, medically inoperable endometrial cancer is feasible with excellent response rates and clinical results. This approach also allows sparing of critical organs and ensures target coverage, which contributed to the low toxicity rate and high LRC in comparison with 2D point-based series.
Abstract
The objective of our study was to evaluate the survival outcome of cervical cancer patients treated using image-guided brachytherapy (IGBT). From 2008 to 2018, 341 patients with cervical ...cancer were treated by radical radiotherapy. IGBT (by computed tomography CT or transabdominal ultrasound TAUS) was used to treat all of these patients. The characteristic data and patient status after treatment were recorded. All data were evaluated for survival outcome analysis. From a total of 341 patients, 295 patients were analyzed and 46 patients were excluded due to data missing in the survival outcomes. At the median follow-up time of 48 months (IQR 30–80 months), The 4-year local control, progression-free survival and overall survival rates were 89.5%, 74.9% and 69.1%, respectively. For overall survival, the size (> 5 cm), pathology (non-SCCA), stage (stage III–IV by FIGO 2009), lymph node (LN) (presented) and overall treatment time (OTT) (> 56 days) showed statistical significance in univariate analysis while non-SCCA pathology, advanced stage, presented LN and longer OTT showed statistical significance in multivariate analysis. In conclusion, our analysis reports a 4-year overall survival rate of 69.1%. Non-SCCA pathology, advanced stage disease, LN presence and longer OTT showed worse prognostic factors in multivariate analysis.
This study retrospectively evaluates clinical outcomes of dose escalation to involved nodes using volumetric modulated arc therapy (VMAT) with simultaneous integrated boost (SIB) for node-positive ...locally advanced cervical cancer (LACC) at a single institution. Consecutive patients with node-positive LACC (FIGO2018 IIIC1-IVA) who received definitive chemoradiotherapy by VMAT 45 Gy in 25 fractions with SIB to 55–57.5 Gy, followed by magnetic resonance image-guided adaptive brachytherapy (IGABT) between 2018 and 2022 were identified. A standardized strategy regarding nodal boost delivery and elective para-aortic (PAO) irradiation was employed. Primary endpoints were involved nodal control (INC) and regional nodal control (RNC). Secondary endpoints were pelvic control (PC), locoregional control (LRC), disease-free survival (DFS), overall survival (OS), failure pattern, and radiotherapy-related toxicities. A total of 234 involved nodes (182 pelvic and 52 PAO) in 54 patients, with a median of 3 involved nodes per patient (range 1–16), were analyzed. After a median follow-up of 19.6 months, excellent INC was achieved, with four (2%) boost-volume failures occurring in three patients. The 2-year actuarial RNC, PC, LRC, DFS, and OS were 93%, 87%, 87%, 78%, and 85%, respectively. Adenocarcinoma histology was associated with worse RNC (p = 0.02) and OS (p = 0.04), whereas the primary tumor maximum standardized uptake value (SUVmax) was associated with worse PC (p = 0.04) and LRC (p = 0.046) on univariate analysis. The incidence of grade ≥3 acute and late radiotherapy-related toxicity were 2% and 4%, respectively. Treatment of node-positive LACC with VMAT with SIB allows safe and effective dose escalation. The 5-year local experience demonstrated excellent treatment outcomes without additional toxicity.
The purpose of this study was to develop a novel quality assurance (QA) program to check the entire treatment chain of image-guided brachytherapy with dose distribution evaluation in a single setup ...and irradiation using a gel dosimeter.
A polymer gel was used, and the readout was performed by magnetic resonance scanning. A CT-based treatment plan was generated using the Oncentra planning system (Elekta, Sweden), and irradiation was performed three times using an afterloading device with an Ir-192 source. The dose-response curve of the gel was created using 6-MV X-ray, which is independent of the source beams. Planar gamma images on a coronal plane along the source transport axis were calculated using the measured dose as a reference, and the calculated doses were used in several error simulations (no error; 2.0 or 2.5 mm systematic and random source dwell mispositioning; and dose error of 2%, 5%, 10%, and 20%).
The dose-R
(spin-spin relaxation rate) conversion table revealed that the uncertainty and dose resolution of 6-MV X-ray were better than those of Ir-192 and also constant between the three measurements. With the 3%/1 mm criteria, there were statistically significant differences between each pair of settings except dose error of 2% and 5%.
This work depicts a simple and efficient end-to-end test that can provide a clinically useful tool for QA of image-guided brachytherapy. In this QA program, air kerma strength and dwell position setting could also be verified. This test can also distinguish between different types of error.
Dramatic advances have been made in brachytherapy for cervical cancer. Radiation treatment planning has evolved from two-dimensional to three-dimensional, incorporating magnetic resonance imaging ...and/or computed tomography into the treatment paradigm. This allows for better delineation and coverage of the tumor, as well as improved avoidance of surrounding organs. Consequently, advanced brachytherapy can achieve very high rates of local control with a reduction in morbidity, compared with historic approaches. This review provides an overview of state-of-the-art gynecologic brachytherapy, with a focus on recent advances and their implications for women with cervical cancer.
The aim of this study was to assess the feasibility of planning dose-volume histogram (DVH) parameters in computed tomography-based 3D image-guided brachytherapy for locally advanced cervical cancer. ...In a prospective multi-institutional study, 60 patients with stage IIA2-IVA cervical cancer from eight institutions were treated with external beam radiotherapy using central shielding and intracavitary or hybrid (combined intracavitary/interstitial) brachytherapy (HBT). The dose constraints were set as a cumulative linear quadratic equivalent dose (EQD2) of at least 60 Gy for high-risk clinical target volume (HR-CTV) D90, D2cc ≤ 75 Gy for rectum, D2cc ≤ 90 Gy for bladder and D2cc ≤ 75 Gy for sigmoid. The median HR-CTV D90 was 70.0 Gy (range, 62.8-83.7 Gy) in EQD2. The median D2cc of rectum, bladder and sigmoid was 57.1 Gy (range, 39.8-72.1 Gy), 68.9 Gy (range, 46.5-84.9 Gy) and 57.2 Gy (range, 39.2-71.2 Gy) in EQD2, respectively. In 76 of 233 sessions (33%), 23 patients underwent HBT, and the median number of interstitial needles was 2 (range, 1-5). HBT for a bulky HR-CTV (≥40 cm3) significantly improved the HR-CTV D90 compared with intracavitary brachytherapy alone (P = 0.010). All patients fulfilled the dose constrains for target and at risk organs by undergoing HBT in one-third of sessions. We conclude that the planning DVH parameters used in our protocol are clinically feasible.