Risk Factors for Local Failure Following Chemoradiation and Magnetic Resonance Image-Guided Brachytherapy in Locally Advanced Cervical Cancer: Results From the EMBRACE-I Study.

PURPOSE: To report clinical and treatment characteristics, remission and failure patterns, and risk factors for local failure (LF) from the EMBRACE-I study. MATERIALS AND METHODS: EMBRACE-I was a prospective, observational, multicenter cohort study on magnetic resonance imaging-based image-guided adaptive brachytherapy (MR-IGABT) in locally advanced cervical cancer. Treatment consisted of external beam radiotherapy, concurrent chemotherapy, and MR-IGABT. LF was defined as progressive or recurrent disease in the cervix, uterus, parametria, pelvic wall, or vagina. Competing risk analysis was used to estimate local tumor control (LC) and Cox proportional regression models for multivariable analysis and dose-response analysis. RESULTS: One thousand three hundred eighteen patients with a median follow-up of 52 months were available for this analysis. Eighty-one patients had persistent disease 3 months after end of treatment. Of those, 60 patients achieved LC at 6-9 months without further treatment, whereas 21 patients had progressive disease. In addition, 77 patients developed a local recurrence after complete remission comprising a total number of 98 LFs. LFs were located inside the MR-IGABT target volumes in 90% of patients with LF. In multivariable analysis, histology, minimal dose to 90% of high-risk clinical target volume (CTVHR), maximum tumor dimension, CTVHR > 45 cm3, overall treatment time, tumor necrosis on magnetic resonance imaging at diagnosis, uterine corpus infiltration at diagnosis and at MR-IGABT, and mesorectal infiltration at MR-IGABT had significant impact on LF. Dose-response analysis showed that a minimal dose to 90% of 85 Gy to the CTVHR led to 95% (95% CI, 94 to 97) LC 3 years postintervention for squamous cell in comparison to 86% (95% CI, 81 to 90) for adeno/adenosquamous carcinoma histology. CONCLUSION: The present study demonstrates the safety and validity of the GYN GEC-ESTRO/ICRU-89 target concept and provides large-scale evidence for dose prescription and new risk factors for LF in MR-IGABT in locally advanced cervical cancer.

Association of persistent morbidity after radiotherapy with quality of life in locally advanced cervical cancer survivors.

PURPOSE: To quantify the association of persistent morbidity with different aspects of quality of life (QOL) in locally advanced cervical cancer (LACC) survivors. MATERIAL AND METHODS: Longitudinal outcome from the EMBRACE-I study was evaluated. Patient-reported symptoms and QOL were prospectively scored (EORTC-C30/CX24) at baseline and regular follow-ups. Physician-assessed symptoms were also reported (CTCAEv.3). Persistent symptoms were defined if present in at least half of the follow-ups. QOL items were linearly transformed into a continuous scale. Linear mixed-effects models (LMM) were applied to evaluate and quantify the association of persistent symptoms with QOL. Overall QOL deterioration was evaluated by calculating the integral difference in QOL over time obtained with LMM for patients without and with persistent symptoms. RESULTS: Out of 1416 patients enrolled, 741 with baseline and ≥ 3 late follow-ups were analyzed (median 59 months). Proportions of persistent EORTC symptoms ranged from 21.8 % to 64.9 % (bowel control and tiredness). For CTCAE the range was 11.3-28.6 % (limb edema and fatigue). Presence of any persistent symptom was associated with QOL, although with varying magnitude. Role functioning and Global health/QOL were the most impaired aspects. Fatigue and pain showed large differences, with reductions of around 20 % for most of the QOL aspects. Among organ-related symptoms, abdominal cramps showed the largest effect. CONCLUSION: Persistent symptoms are associated with QOL reductions in LACC survivors. Organ-related symptoms showed smaller differences than general symptoms such as fatigue and pain. In addition to optimizing treatment to minimize organ-related morbidity, effort should be directed towards a more comprehensive and targeted morbidity management.

Dose-effect relationship between vaginal dose points and vaginal stenosis in cervical cancer: An EMBRACE-I sub-study.

BACKGROUND AND PURPOSE: To evaluate dose-effect relationships between vaginal dose points and vaginal stenosis in patients treated for locally advanced cervical cancer with radio(chemo)therapy and image-guided adaptive brachytherapy. MATERIAL AND METHODS: Patients from six centres participating in the EMBRACE-I study were included. Information on doses to different vaginal dose points, including the Posterior-Inferior Border of Symphysis (PIBS) points and recto-vaginal reference (RV-RP) point, were retrieved from the treatment planning system. In addition, the vaginal reference length (VRL) was evaluated. Vaginal stenosis was prospectively assessed according to the CTCAEv3.0 system at baseline and follow-up. Primary endpoint was grade 2 or higher (G ≥ 2) vaginal stenosis. Impact of dose to the vaginal dose points, and impact of VRL, age, vaginal involvement and applicator on vaginal stenosis G ≥ 2 was evaluated with a Cox proportional-hazard regression model. RESULTS: 301 patients were included. Median follow-up was 49 months. During follow-up, the incidence of G0, G1, G2, and G3 vaginal stenosis was 25% (76), 52% (158), 20% (59) and 3% (8), respectively. Median total doses to PIBS+2 cm, PIBS, PIBS-2 cm and the RV-RP were 52.9 (IQR 49.3-64.7), 41.0 (IQR 15.4-49.0), 4.1 (IQR 2.9-7.0) and 64.6 (IQR 60.0-70.6) Gy EQD23, respectively. Higher doses to the PIBS, PIBS + 2 cm and RV-RP points were significantly associated with increased risk for vaginal stenosis G ≥ 2. Other risk factors for vaginal stenosis were: vaginal involvement at diagnosis, higher age, shorter VRL and use of a tandem-ovoid applicator. CONCLUSION: Higher doses to the PIBS+2 cm, PIBS and RV-RP dose points are associated with vaginal stenosis G ≥ 2.

Impact of Vaginal Symptoms and Hormonal Replacement Therapy on Sexual Outcomes After Definitive Chemoradiotherapy in Patients With Locally Advanced Cervical Cancer: Results from the EMBRACE-I Study.

PURPOSE: To evaluate patient-reported sexual outcomes after chemoradiation therapy and image-guided adaptive brachytherapy for locally advanced cervical cancer in the observational, prospective, multicenter EMBRACE-I study. METHODS AND MATERIALS: Sexual outcomes were assessed prospectively with the European Organization for Research and Treatment of Cancer Qualify of Life Questionnaire (EORTC-QLQ-CX24) at baseline and follow-up. Crude incidence and prevalence rates of sexual activity, vaginal functioning problems (dryness, shortening, tightening, pain during intercourse), and sexual enjoyment were evaluated. Associations between pain during intercourse and vaginal functioning problems or sexual enjoyment were calculated, pooling observations over all follow-ups (Spearman correlation coefficient). In patients who were frequently sexually active (≥50% of follow-ups), the effects of regular hormonal replacement therapy (HRT) on vaginal functioning problems were evaluated (Pearson χ2). RESULTS: The analysis involved 1045 patients with a median follow-up of 50 months. Sexual activity was reported by 22% of patients at baseline and by 40% to 47% of patients during follow-up (prevalence rates). Vaginal functioning problems in follow-up were dryness (18%-21%), shortening (15%-22%), tightening (16%-22%), pain during intercourse (9%-21%), and compromised enjoyment (37%-47%). Pain during intercourse was significantly associated with vaginal tightening (r = 0.544), shortening (r = 0.532), and dryness (r = 0.408) and negatively correlated with sexual enjoyment (r = -0.407). Regular HRT was associated with significantly less vaginal dryness (P = .015), shortening (P = .024), pain during intercourse (P = .003), and borderline higher sexual enjoyment (P = .062). CONCLUSIONS: Vaginal functioning problems are associated with pain and compromised sexual enjoyment. Further effort is required for the primary prevention of vaginal morbidity with dose optimization and adaptation. Secondary prevention strategies, including HRT for vaginal and sexual health after radiation therapy in locally advanced cervical cancer, should be considered and sexual rehabilitation programs should be developed further.

Severity and Persistency of Late Gastrointestinal Morbidity in Locally Advanced Cervical Cancer: Lessons Learned From EMBRACE-I and Implications for the Future.

PURPOSE: The purpose was to evaluate patient- and treatment-related risk factors for physician-assessed and patient-reported gastrointestinal (GI) symptoms after radio(chemo)therapy and image guided adaptive brachytherapy in locally advanced cervical cancer. METHODS AND MATERIALS: Of 1416 patients from the EMBRACE-I study, 1199 and 1002 were prospectively evaluated using physician-assessed (Common Terminology Criteria for Adverse Events [CTCAE]) and patient-reported (European Organization for Research and Treatment of Cancer [EORTC]) GI symptoms, respectively. CTCAE severe grade (grade [G] ≥3) events were pooled according to the location in the GI tract (anus/rectum, sigmoid, and colon/small bowel). CTCAE G ≥2 and EORTC "very much" and "quite a bit" plus "very much" scores (≥ "quite a bit") were analyzed for individual symptoms with Cox regression. Logistic regression was used for persistent G ≥1 and EORTC ≥ "quite a bit" symptoms, defined if present in at least half of follow-ups. RESULTS: The incidence of G ≥3 events was 2.8%, 1.8%, and 2.3% for G ≥3 anus/rectum, sigmoid, and colon/small bowel events, respectively. Among G ≥2 symptoms, diarrhea and flatulence were the most prevalent (8.5% and 9.9%, respectively). Among patient-related factors, baseline morbidity, increasing age, smoking status, and low body mass index were associated with GI symptoms to varying degrees. Among treatment-related factors, rectum D2cm3 and the International Commission on Radiation Units and Measurements recto-vaginal reference point (ICRU RV-RP) correlated with G ≥3 anus/rectum events and moderate/persistent diarrhea, proctitis, bleeding, abdominal cramps, and difficulty in bowel control. Bowel D2cm3 correlated with G ≥3 sigmoid and colon/small bowel events and moderate/persistent diarrhea and flatulence. For external beam radiation therapy (EBRT), prescription dose correlated with G ≥3 anus/rectum, diarrhea, and difficulty in bowel control. Patients with large lymph-node boost (V57Gy) were at higher risk for G ≥3 sigmoid events, moderate/persistent diarrhea, proctitis, and cramps. CONCLUSIONS: The analysis showed that both EBRT and image guided adaptive brachytherapy contribute to GI symptoms after locally advanced cervical cancer treatment. Rectum D2cm3, ICRU RV-RP , and bowel D2cm3 are risk factors for GI morbidity. The risk for various symptoms was lower with an EBRT prescription of 45 Gy than 50 Gy and increased with larger V57Gy.

Risk factors for nodal failure after radiochemotherapy and image guided brachytherapy in locally advanced cervical cancer: An EMBRACE analysis.

OBJECTIVE: To assess risk factors for nodal failure (NF) after definitive (chemo)radiotherapy and image-guided brachytherapy for locally advanced cervical cancer (LACC) for patients treated in the EMBRACE I study. MATERIALS AND METHODS: Data for pelvic NF and para-aortic (PAO) NF (NFPAO) were analysed. After multiple imputation, univariable and multivariable Cox-regression was performed for clinical and treatment-related variables. For patients with affected pelvic nodes but no PAO nodes at diagnosis, additional analyses were performed for two subgroups: 1. 'small pelvis' nodes in internal and external iliac, obturator, parametrial, presacral and/or common iliac (CI) region and 2. any CI nodes (subgroup of 1). RESULTS: 1338 patients with 152 NF and 104 NFPAO events were analysed with a median follow-up of 34.2 months (IQR 16.4-52.7). For the entire group, larger tumour width, nodal risk groups (in particular any CI nodes without PAO nodes), local failure, and lower Hb-nadir increased the risk of NF. Elective PAO-irradiation was independently associated with a decreased risk of NFPAO (HR 0.53, 95%-CI 0.28-1.00, p = 0.05). For subgroup 1, having 'any CI nodes without PAO nodes' and local failure significantly increased NF risk. Additionally, elective PAO-irradiation was associated with less risk of NFPAO (HR 0.38, 95%-CI 0.17-0.86, p = 0.02). For subgroup 2 only local failure was associated with higher risk of NF. CONCLUSION: In this patient cohort, nodal disease and tumour width at diagnosis, as well as local failure, are risk factors for NF after definitive treatment. Having either 'any PAO nodes' (with or without pelvic nodes) or 'any CI nodes' (without PAO nodes) are stronger risk factors than involvement of nodes in the small pelvis alone. Elective PAO-irradiation was associated with significantly less NFPAO, particularly in patients with nodal disease in the 'small pelvis' and/or CI region at time of diagnosis.

Dosimetric impact of edema on inguinal lymph node boost in locally advanced vulvar cancer.

We aimed to evaluate the extent of groin edema and its dosimetric effect in boosted inguinal lymph nodes (LN) for vulvar cancer patients. The level of edema was determined in 10 patients treated with radical radiotherapy. A dosimetric evaluation of six LNs in the patient with the maximum level of edema was performed. The accumulated dose across CBCT fractions was acceptable for all six LNs (>94% of prescribed dose) even with the development of up to 13 mm of edema. The major contributor to fractional dose degradation was geographical displacement of the nodes. We suggest evaluation of edema on daily CBCT.

Image-Guided Adaptive Brachytherapy (IGABT) for Primary Vaginal Cancer: Results of the International Multicenter RetroEMBRAVE Cohort Study.

PURPOSE: This study assessed outcomes following the nowadays standing treatment for primary vaginal cancer with radio(chemo)therapy and image-guided adaptive brachytherapy (IGABT) in a multicenter patient cohort. METHODS: Patients treated with computer tomography (CT)-MRI-assisted-based IGABT were included. Retrospective data collection included patient, tumor and treatment characteristics. Late morbidity was assessed by using the CTCAE 3.0 scale. RESULTS: Five European centers included 148 consecutive patients, with a median age of 63 years. At a median follow-up of 29 months (IQR 25-57), two- and five-year local control were 86% and 83%; disease-free survival (DFS) was 73% and 66%, and overall survival (OS) was 79% and 68%, respectively. Crude incidences of ≥ grade-three urogenital, gastro-intestinal and vaginal morbidity was 8%, 3% and 8%, respectively. Lymph node metastasis was an independent prognostic factor for disease-free survival (DFS). Univariate analysis showed improved local control in patients with T2-T4 tumors if >80 Gy EQD2α/ß10 was delivered to the clinical target volume (CTV) at the time of brachytherapy. CONCLUSIONS: In this large retrospective multicenter study, IGABT for primary vaginal cancer resulted in a high local control with acceptable morbidity. These results compared favorably with two-dimensional (2D) radiograph-based brachytherapy and illustrate that IGABT plays an important role in the treatment of vaginal cancer.

Risk factors and dose-effects for bladder fistula, bleeding and cystitis after radiotherapy with imaged-guided adaptive brachytherapy for cervical cancer: An EMBRACE analysis.

PURPOSE: To identify patient- and treatment-related risk factors for fistula, bleeding, cystitis, pain and difficulty in voiding in locally advanced cervical cancer patients treated with radio(chemo)therapy and image-guided adaptive brachytherapy (IGABT). MATERIAL AND METHODS: Morbidity within the EMBRACE-I study was prospectively reported for physician-assessed (CTCAE) fistula, bleeding and cystitis and patient-reported (EORTC) pain and difficulty in voiding. Analysis of risk factors was performed in patients without bladder infiltration. Risk factors were tested with Cox regression for grade (G) ≥ 3 cystitis, for G ≥ 2 fistula, bleeding and cystitis, and for EORTC "very much" and "quite a bit" or worse. RESULTS: Of 1416 patients enrolled, 1153 and 884 patients without bladder infiltration were evaluable for the analysis of CTCAE and EORTC items, respectively. Median follow-up was 48[3-120] months. Crude incidence rates for G ≥ 2 fistula, bleeding and cystitis were 0.7%, 2.7% and 8.8%, respectively, and 16% and 14% for "quite a bit" or worse pain and difficulty in voiding, respectively. Baseline urinary morbidity and overweight/obesity were significant risk factors for most endpoints. Bladder D2cm3 correlated with G ≥ 2 fistula, bleeding and cystitis, while ICRU bladder point dose correlated with EORTC pain "quite a bit" or worse. An increase from 75 Gy to 80 Gy in bladder D2cm3 resulted in an increase from 8% to 13% for 4-year actuarial estimate of G ≥ 2 cystitis. CONCLUSION: Clinical and treatment-related risk factors for bladder fistula, bleeding and cystitis were identified within a prospective and multi-institutional setting. A dose-effect was established with bladder D2cm3, reinforcing the importance of continued optimization during individualized IGABT planning.

Results of image guided brachytherapy for stage IB cervical cancer in the RetroEMBRACE study.

OBJECTIVE: Multiple treatment options are used in early local-stage cervical cancer, including combinations of surgery with neoadjuvant/adjuvant radiotherapy and chemotherapy. Our aim was to determine the outcome for definitive chemoradiation with image guided brachytherapy (IGBT). METHODS: FIGO1994 staging system was used in our study. We included 123 patients with stage IB cervical cancer, treated at 12 centers with external beam radiotherapy (EBRT) ± Chemotherapy and IGBT. Three- and 5-year actuarial local control (LC), pelvic control (PC), overall survival (OS), cancer-specific survival (CSS) and late morbidity (CTCAE v 3.0) were computed. RESULTS: Median age was 48 (23-82) years. FIGO1994 stage distribution was: IB1 68% and IB2 32%; 41% of the entire cohort had nodal metastases and 73% squamous-cell carcinoma. MRI-based tumor size was >40 mm in 63%. Median EBRT dose was 45 (40-50) Gy; 84% received chemotherapy. At IGBT, mean CTV-HR D90 was 93 ± 17 Gy (EQD210). D2cc for bladder was 76 ± 14 Gy, rectum 66 ± 11 Gy, sigmoid 66 ± 10 Gy, bowel 67 ± 7 Gy (EQD23). At 43-months median follow-up, 9% of patients had systemic, 6% paraaortic, 3% pelvic-nodal and 2% local failure. Five-year LC was 98%, PC 96%, CSS 90%, OS 83%. Intestinal G3--4 morbidity was 8%, urinary 7% and vaginal 0%. CONCLUSIONS: Chemoradiation with IGBT for FIGO1994 stage IB cervical cancer leads to excellent loco-regional control with limited morbidity. In IB node-negative disease, it can be regarded equivalent to surgery in terms of oncologic outcome. In tumors with unfavorable pre-treatment characteristics, chemoradiation is the first choice to avoid combining surgery with adjuvant therapy.

Persistence of Late Substantial Patient-Reported Symptoms (LAPERS) After Radiochemotherapy Including Image Guided Adaptive Brachytherapy for Locally Advanced Cervical Cancer: A Report From the EMBRACE Study.

PURPOSE: This report describes the persistence of late substantial treatment-related patient-reported symptoms (LAPERS) in the multi-institutional EMBRACE study on magnetic resonance image guided adaptive brachytherapy in locally advanced cervical cancer (LACC). METHODS AND MATERIALS: Patient-reported symptoms (European Organization for Research and Treatment of Cancer [EORTC]-C30/CX24) and physician-assessed morbidity (Common Terminology Criteria for Adverse Events [CTCAE], version 3.0) were assessed at baseline and regular timepoints during follow-up. Patients with sufficient EORTC follow-up (baseline and ≥3 late follow-up visits) were analyzed. LAPERS events were defined as the presence of substantial EORTC symptoms (quite a bit/very much) for at least half of the assessments (persistence) and progression beyond baseline condition (treatment-related). For each EORTC symptom, the ratio between LAPERS rates and crude incidence rates of substantial symptoms was calculated to represent the proportion of symptomatic patients with persisting symptoms. For 9 symptoms with a corresponding EORTC/CTCAE assessment, the overlap of LAPERS and severe morbidity events (grades 3-5) was evaluated. RESULTS: Of 1047 patients with EORTC available, 741 had sufficient follow-up for the LAPERS analyses. The median follow-up was 59 months (interquartile range, 42-70 months). Across all symptoms, the proportion of patients with LAPERS events (LAPERS rates) was in median 4.6% (range, 0.0% vaginal bleeding to 20.4% tiredness). Urinary frequency, neuropathy, fatigue, insomnia, and menopausal symptoms revealed LAPERS rates of >10%. Vomiting, blood in stool, urinary pain/burning, and abnormal vaginal bleeding displayed LAPERS rates of <1%. A median of 19% of symptomatic patients (interquartile range, 8.0%-28.5%) showed persistent long-term symptoms (LAPERS events). In symptoms with a corresponding EORTC/CTCAE assessment, 12% of LAPERS events were accompanied by a severe CTCAE event. CONCLUSIONS: Within this large cohort of survivors of LACC, a subgroup of patients with persistent symptoms (LAPERS events) was identified. For symptoms with a corresponding EORTC/CTCAE assessment, the vast majority of LAPERS events occurred in patients without corresponding severe physician-assessed morbidity. These findings emphasize the importance of distinguishing between transient and persisting symptoms in the aftercare of LACC survivors.

Importance of the ICRU bladder point dose on incidence and persistence of urinary frequency and incontinence in locally advanced cervical cancer: An EMBRACE analysis.

PURPOSE: To identify patient- and treatment-related risk factors and dose-effects for urinary frequency and incontinence in locally advanced cervical cancer (LACC) treated with radio(chemo)therapy and image-guided adaptive brachytherapy (IGABT). MATERIAL AND METHODS: Physician-assessed (CTCAE) and patient-reported (EORTC) frequency and incontinence recorded in the EMBRACE-I study were analysed. Risk factors analysis was performed in patients without bladder infiltration and with baseline morbidity available. Cox regression was used for CTCAE grade (G) ≥ 3 and G ≥ 2 and for EORTC "very much" and "quite a bit" or worse. Logistic regression was used for late persistent morbidity defined when CTCAE G ≥ 1 or EORTC ≥ "quite a bit" were scored in at least half of follow-ups. RESULTS: Longitudinal data on 1153 and 884 patients were available for CTCAE and EORTC analysis, respectively. Median follow-up was 48[3-120] months. Crude incidence rates of G≥2 were 13% and 11% for frequency and incontinence, respectively. Baseline morbidity and overweight-obesity were risk factors for both symptoms. Elderly patients were at higher risk for incontinence. Patients receiving conformal-radiotherapy were at higher risk for frequency. ICRU bladder point (ICRU-BP) dose was a stronger predictor for incontinence than bladder D2cm3. The 5-year actuarial estimate of G ≥ 2 incontinence increased from 11% to 20% with ICRU-BP doses > 75 Gy compared to ≤ 65 Gy. Frequency showed weaker associations with dose. CONCLUSION: ICRU-BP dose, in addition to clinical parameters, is a risk factor for urinary incontinence and shows a dose-effect after radio(chemo)therapy and IGABT. ICRU-BP dose should be monitored during treatment planning alongside volumetric parameters. Frequency seems associated with larger irradiated volumes.

Dose-Volume Effects and Risk Factors for Late Diarrhea in Cervix Cancer Patients After Radiochemotherapy With Image Guided Adaptive Brachytherapy in the EMBRACE I Study.

PURPOSE: To evaluate patient- and treatment-related risk factors associated with incidence and persistence of late diarrhea after radiochemotherapy and image guided adaptive brachytherapy (IGABT) in locally advanced cervical cancer. MATERIALS AND METHODS: Of 1416 patients from the EMBRACE I study, 1199 were prospectively evaluated using physician-reported (Common Terminology Criteria for Adverse Events version 3 [CTCAEv3]) assessment for diarrhea; median follow-up 48 months. Patient-reported outcome (EORTC) was available in 900 patients. Incidence of CTCAE G≥2, G≥3, and EORTC "very much" diarrhea was analyzed with Cox proportional hazards regression. Binary logistic regression was used for analysis of persistent G≥1 and EORTC "quite a bit" - "very much" (≥"quite a bit") diarrhea, defined if present in at least half of all follow-ups. RESULTS: Crude incidences of G≥2 and G≥3 diarrhea were 8.3% and 1.5%, respectively, and 8% of patients reported "very much" diarrhea. Persistent G≥1 and ≥"quite a bit" diarrhea was present in 16% and 7%, respectively. Patient-related risk factors were baseline diarrhea, smoking, and diabetes with hazard ratios of 1.4 to 7.3. Treatment-related risk factors included prescribed dose, V43 Gy, V57 Gy (lymph node boost), and para-aortic irradiation for external beam radiation therapy (EBRT). G≥2 diarrhea at 3 years increased from 9.5% to 19.9% with prescribed dose 45 Gy versus 50 Gy, 8.7% to 14.0% with V43 Gy <2500 cm3 versus >3000 cm3 and 9.4% to 19.0% with V57 Gy <165 cm3 versus ≥165 cm3. Brachytherapy-related bowel and rectum D2cm3 were also associated with diarrhea. CONCLUSION: Dose and volume effects have been established for late diarrhea after radiochemotherapy and IGABT in both CTCAE and EORTC reporting. The risk of diarrhea was lower with a pelvic EBRT prescription of 45 Gy, and higher with larger lymph node boosts volumes (ie, ≥165 cm3). The importance of EBRT volumes as determinants of late toxicity underline the need for continuous quality assurance of target contouring, dose planning, and conformity. The findings of brachytherapy dosimetric factors related to the intestines may become more important with highly conformal EBRT.

Initiatives for education, training, and dissemination of morbidity assessment and reporting in a multiinstitutional international context: Insights from the EMBRACE studies on cervical cancer.

In 2008, the GEC ESTRO Gyn network launched the first multiinstitutional, observational, and prospective international study on MRI-guided brachytherapy in locally advanced cervical cancer patients (EMBRACE-I). EMBRACE-I was followed by EMBRACE-II from 2016 and ongoing. Among the aims of the EMBRACE studies are to benchmark morbidity outcomes and develop dose-volume effects and predictive models for morbidity. The EMBRACE studies collect both physician (CTCAE v.3) and patient (EORTC QLQ-C30/CX24) reported outcomes, including baseline information, in a regular follow-up schedule. The EMBRACE studies feature high numbers of patients (EMBRACE-I N = 1416, EMBRACE-II N = 1500 expected) enrolled from many institutions worldwide (EMBRACE-I n = 23, EMBRACE-II n = 45). This large-scale multiinstitutional approach offers a unique opportunity to investigate and develop new strategies for improving the quality of assessment and reporting of morbidity. This report presents an overview of the challenges and pitfalls regarding the assessment and reporting of morbidity encountered during more than a decade of development and research activities within the EMBRACE consortium. This includes the recognition and evaluation of inconsistencies in the morbidity assessment, and consequently, the provision of assistance and training in the scoring procedure to reduce systematic assessment bias. In parallel, a variety of methodological approaches were tested to comprehensively summarize morbidity outcomes, and a novel approach was developed to refine dose-effect models and risk factor analyses. The purpose of this report is to present an overview of these findings, describe the learning process, and the strategies that have consequently been implemented regarding educational activities, training, and dissemination.

Implementing an online radiotherapy quality assurance programme with supporting continuous medical education - report from the EMBRACE-II evaluation of cervix cancer IMRT contouring.

BACKGROUND AND PURPOSE: EMBRACE-II is an international prospective study of IMRT and MRI-guided adaptive brachytherapy (IGABT) in locally advanced cervix cancer. An online radiotherapy quality assurance (RTQA) programme with minimal data transfer and supporting continuing medical education (CME) was implemented for IMRT contouring. MATERIALS AND METHODS: Participant contours for six volumes-of-interest (VOIs) on one benchmark case were scored (2 = excellent, 1 = fair, 0 = revision required) against a consensus reference contour. For contours receiving a 0 or 1 score, additional qualitative comments were provided. The Jaccard conformity index (JCI) was retrospectively calculated. User interaction with CME content (pre-accreditation questionnaire, contouring atlas, practice cases, quizzes, internal target volume (ITV-T) guide) was analysed. RESULTS: 78 clinicians submitted contours for evaluation. 41% passed at the first attempt, 44% after one revision and 6% after two or more revisions. 9% did not re-submit after failing. The lowest mean scores were for the elective nodal CTV (CTV-E) (1.01/2) and ITV-T (1.06/2). 60 different errors across the six VOIs were identified; five potentially had high impact on loco-regional control. A JCI cut-off of 0.7 would have identified 87% contours that failed expert assessment, but also excluded 54% of passing contours. 39 clinicians responded to the pre-accreditation questionnaire - 36% anticipated difficulties with the ITV-T and 13% with the CTV-E. 35% clinicians contoured on the practice cases, 17% answered a quiz, 96% used the atlas and 38% the ITV-T guide. CONCLUSION: Expert evaluation with qualitative feedback improved contouring compliance. The JCI is not a reliable alternative to expert assessment. Moderate uptake of optional CME content limited evaluation.

MRI-based contouring of functional sub-structures of the lower urinary tract in gynaecological radiotherapy.

INTRODUCTION: Research in radiation-induced urinary morbidity is limited by lack of guidelines for contouring and dose assessment of the lower urinary tract. Based on literature regarding anatomy, physiology and imaging of the lower urinary tract, this study aimed to provide advice on contouring of relevant sub-structures, reference points and reference dimensions for gynaecological radiotherapy. MATERIAL AND METHODS: 210 MRIs for Image-Guided Adaptive Brachytherapy (IGABT) were analysed in 105 locally advanced cervical cancer patients treated with radio(chemo)therapy. Sub-structures (trigone, bladder neck and urethra) were contoured and trigone height (TH) and width (TW) were measured. Internal urethral ostium (IUO) and Posterior inferior border of pubic symphysis-urethra (PIBS-U) points were used to identify proximal and middle/low urethra, respectively. Urethra reference length (URL) was defined as IUO and PIBS-U distance. TH, TW and URL were also quantified on 54 MRIs acquired for External Beam Radiotherapy (EBRT). RESULTS: Median absolute differences in volumes and dimensions between first and second IGABT fraction were 0.7 cm3, 4.3 cm3, 0.2 cm, 0.3 cm and 0.2 cm for trigone, bladder neck, TH, TW and URL, respectively. Mean(±SD) TH and TW were 2.7(±0.4)cm and 4.4(±0.4)cm, respectively, with no significant difference (p = 0.15 and p = 0.06, respectively) between IGABT and EBRT. URL was significantly shorter in EBRT than in IGABT MRIs (p < 0.001). CONCLUSIONS: This study proposed relevant urinary sub-structures and dose points and showed that standardized contouring is reproducible. Trigone reference dimensions are robust despite different bladder filling and treatment conditions. Standardized contouring and reference points may improve understanding of urinary morbidity.

Nodal failure after chemo-radiation and MRI guided brachytherapy in cervical cancer: Patterns of failure in the EMBRACE study cohort.

PURPOSE/OBJECTIVE(S): To investigate the patterns of nodal failure in patients enrolled in the international multicentre EMBRACE study. MATERIALS/METHODS: Nodal disease at diagnosis (N-, N+) and nodal failure were analysed per region (NF) (pelvic (parametrial, common iliac, internal/external iliac), inguinal and para-aortic (PAO)) in 1338 patients. Treatment consisted of chemo-radiation and MRI guided brachytherapy. PAO radiotherapy and/or nodal boost was left to the treating centre. At time of diagnosis 52% of patients had pathologic nodes. Frequency analyses were performed in relation to patient, primary tumour and nodal disease characteristics, and treatment related factors. RESULTS: Median follow up was 34 months and 83% of NF occurred within 24 months. At diagnosis 99% of the N+ patients had pathologic nodes in the pelvis and 14% in the PAO. NFpelvic and NFPAO were reported in 55% and 68% of patients with NF, respectively. Overall NF was reported in 152 patients (11%); 7 and 16% for N- and N+ patients. Of the patients with NF, 41% were located outside the elective target (39% PAO), 40% inside and 35% inside the nodal boost target. Twelve percent of N+ patients that received a nodal boost had a NF inside the nodal boost target. CONCLUSION: Within the EMBRACE study cohort the overall number of patients developing nodal failure is low, significantly lower for N- compared to N+ patients. Pathological nodes at diagnosis are mainly located in the pelvis, whereas nodal failures are more often reported in the PAO region. About 40% of all nodal failures were reported outside the treatment targets.

Importance of Technique, Target Selection, Contouring, Dose Prescription, and Dose-Planning in External Beam Radiation Therapy for Cervical Cancer: Evolution of Practice From EMBRACE-I to II.

PURPOSE: To describe the evolution of external beam radiation therapy (EBRT) from EMBRACE-I (general guidelines for EBRT) to the initial phase of the EMBRACE-II study (detailed protocol for EBRT). METHODS AND MATERIALS: EMBRACE-I enrolled 1416 locally advanced cervical cancer patients treated with chemoradiation including image-guided adaptive brachytherapy during 2008 to 2015. From March 2016 until March 2018, 153 patients were enrolled in the ongoing EMBRACE-II study, which involves a comprehensive detailed strategy and accreditation procedure for EBRT target contouring, treatment planning, and image guidance. EBRT planning target volumes (PTVs), treated volumes (V43 Gy), and conformity index (CI; V43 Gy/PTV) were evaluated in both studies and compared. RESULTS: For EMBRACE-I, conformal radiation therapy (60% of patients) or intensity-modulated radiation therapy (IMRT) and volumetric arc therapy (VMAT; 40%) was applied with 45 to 50 Gy over 25 to 30 fractions to the elective clinical target volume (CTV). For pelvic CTVs (82%), median PTV and V43 Gy volumes were 1549 and 2390 mL, respectively, and CI was 1.54. For pelvic plus paraortic nodal (PAN) CTVs (15%), median PTV and V43 Gy volumes were 1921 and 2895 mL, and CI was 1.51. For pelvic CTVs treated with 45 to 46 Gy, the use of conformal radiation therapy was associated with a median V43 Gy volume that was 546 mL larger than with IMRT/VMAT. For pelvic CTVs treated with IMRT, the use of a dose prescription ≥48 Gy was associated with a median V43 Gy volumes that was 428 mL larger than with a dose prescription of 45 to 46 Gy. For EMBRACE-II, all patients were treated with: IMRT/VMAT, daily IGRT, 45 Gy over 25 fractions for the elective CTV, and simultaneously integrated boost for pathologic lymph nodes. For pelvic CTVs (61%), median PTV and V43 Gy volumes were 1388 and 1418 mL, and CI was 1.02. For pelvic plus PAN CTVs (32%), median PTV and V43 Gy volumes were 1720 and 1765 mL, and CI was 1.03. From EMBRACE-I to initial II, median V43 Gy was decreased by 972 mL (41%) and 1130 mL (39%), and median CI decreased from 1.54 to 1.02 and 1.51 to 1.03 for pelvic and pelvic plus PAN irradiation, respectively. CONCLUSIONS: Application of IMRT/VMAT, IGRT, and a 45-Gy dose provides the potential of higher conformality inducing significant reduction of treated volume. Adherence to a detailed protocol including comprehensive accreditation, as in EMBRACE-II, reduces considerably V43 Gy and V50 Gy and improves conformality and interinstitutional consistency.

Robustness of elective lymph node target coverage with shrinking Planning Target Volume margins in external beam radiotherapy of locally advanced cervical cancer.

BACKGROUND AND PURPOSE: Image-Guidance decreases set-up uncertainties, which may allow for Planning Target Volume (PTV) margins reduction. This study evaluates the robustness of the elective lymph node target coverage to translational and rotational set-up errors in combination with shrinking PTV margins and determines the gain for the Organs At Risk (OARs). MATERIAL AND METHODS: Ten cervix cancer patients who underwent external beam radiotherapy with 45 Gy/25Fx were analysed. Daily Image-Guidance was based on bony registration of Cone Beam CT (CBCT) to planning CT (pCT) and daily couch correction (translation and yaw). On each pCT, four Volumetric Modulated Arc Therapy dose-plans were generated with PTV margins of 0, 3, 5 and 8 mm. The elective clinical target volume (CTV-E) was propagated from daily CBCTs to the pCT to evaluate daily CTV-E dose. Additional systematic translational isocenter shifts of 2 mm were simulated. D98% (dose received by 98% of the volume of interest) and D99.9% were extracted from each CTV-E for all dose-plans and scenarios. Total dose was accumulated by Dose-Volume Histogram addition. The dosimetric impact of PTV margin reduction on the OARs was evaluated through V30Gy (volume included within the 30 Gy isodose), V40Gy and body V43Gy. RESULTS: When decreasing the PTV margin from 5 to 0 mm, bowel V30Gy was decreased by 13% (from 247 cm3 to 214 cm3), body V43Gy by 19% (from 1462 cm3 to 1188 cm3) and PTV by 39% (from 1416 to 870 cm3). The dosimetric impact of combined systematic shifts and residual rotations on the elective target with a 0 mm PTV margin was a decrease of D98% (mean ±â€¯SD) from 44.1 Gy ±â€¯0.4 Gy to 43.7 Gy ±â€¯0.8 Gy and a minimum of 42.4 Gy. CONCLUSION: PTV margin reduction from 5 to 0 mm induced significant OARs dosimetric gains while elective target coverage remained robust to positioning uncertainties.