Combined external beam radiotherapy and vaginal brachytherapy versus vaginal brachytherapy in stage I, intermediate- and high-risk cases of endometrium carcinoma

Stability and Reproducibility of Radiomic Features Based on Various Segmentation Techniques on Cervical Cancer DWI-MRI

Cervical cancer is the most common cancer and ranked as 4th in morbidity and mortality among Malaysian women. Currently, Magnetic Resonance Imaging (MRI) is considered as the gold standard imaging modality for tumours with a stage higher than IB2, due to its superiority in diagnostic assessment of tumour infiltration with excellent soft-tissue contrast. In this research, the robustness of semi-automatic segmentation has been evaluated using a flood-fill algorithm for quantitative feature extraction, using 30 diffusion weighted MRI images (DWI-MRI) of cervical cancer patients. The relevant features were extracted from DWI-MRI segmented images of cervical cancer. First order statistics, shape features, and textural features were extracted and analysed. The intra-class relation coefficient (ICC) was used to compare 662 radiomic features extracted from manual and semi-automatic segmentations. Notably, the features extracted from the semi-automatic segmentation and flood filling algorithm (average ICC = 0.952 0.009, p > 0.05) were significantly higher than the manual extracted features (average ICC = 0.897 0.011, p > 0.05). Henceforth, we demonstrate that the semi-automatic segmentation is slightly expanded to manual segmentation as it produces more robust and reproducible radiomic features.

Fully automated segmentation of clinical target volume in cervical cancer from magnetic resonance imaging with convolutional neural network

PURPOSE

Contouring clinical target volume (CTV) from medical images is an essential step for radiotherapy (RT) planning. Magnetic resonance imaging (MRI) is used as a standard imaging modality for CTV segmentation in cervical cancer due to its superior soft-tissue contrast. However, the delineation of CTV is challenging as CTV contains microscopic extensions that are not clearly visible even in MR images, resulting in significant contour variability among radiation oncologists depending on their knowledge and experience. In this study, we propose a fully automated deep learning-based method to segment CTV from MR images.

METHODS

Our method begins with the bladder segmentation, from which the CTV position is estimated in the axial view. The superior-inferior CTV span is then detected using an Attention U-Net. A CTV-specific region of interest (ROI) is determined, and three-dimensional (3-D) blocks are extracted from the ROI volume. Finally, a CTV segmentation map is computed using a 3-D U-Net from the extracted 3-D blocks.

RESULTS

We developed and evaluated our method using 213 MRI scans obtained from 125 patients (183 for training, 30 for test). Our method achieved (mean ± SD) Dice similarity coefficient of 0.85 ± 0.03 and the 95th percentile Hausdorff distance of 3.70 ± 0.35 mm on test cases, outperforming other state-of-the-art methods significantly (p-value < 0.05). Our method also produces an uncertainty map along with the CTV segmentation by employing the Monte Carlo dropout technique to draw physician's attention to the regions with high uncertainty, where careful review and manual correction may be needed.

CONCLUSIONS

Experimental results show that the developed method is accurate, fast, and reproducible for contouring CTV from MRI, demonstrating its potential to assist radiation oncologists in alleviating the burden of tedious contouring for RT planning in cervical cancer.

Fully automated multiorgan segmentation of female pelvic magnetic resonance images with coarse-to-fine convolutional neural network

PURPOSE

Brachytherapy combined with external beam radiotherapy (EBRT) is the standard treatment for cervical cancer and has been shown to improve overall survival rates compared to EBRT only. Magnetic resonance (MR) imaging is used for radiotherapy (RT) planning and image guidance due to its excellent soft tissue image contrast. Rapid and accurate segmentation of organs at risk (OAR) is a crucial step in MR image-guided RT. In this paper, we propose a fully automated two-step convolutional neural network (CNN) approach to delineate multiple OARs from T2-weighted (T2W) MR images.

METHODS

We employ a coarse-to-fine segmentation strategy. The coarse segmentation step first identifies the approximate boundary of each organ of interest and crops the MR volume around the centroid of organ-specific region of interest (ROI). The cropped ROI volumes are then fed to organ-specific fine segmentation networks to produce detailed segmentation of each organ. A three-dimensional (3-D) U-Net is trained to perform the coarse segmentation. For the fine segmentation, a 3-D Dense U-Net is employed in which a modified 3-D dense block is incorporated into the 3-D U-Net-like network to acquire inter and intra-slice features and improve information flow while reducing computational complexity. Two sets of T2W MR images (221 cases for MR1 and 62 for MR2) were taken with slightly different imaging parameters and used for our network training and test. The network was first trained on MR1 which was a larger sample set. The trained model was then transferred to the MR2 domain via a fine-tuning approach. Active learning strategy was utilized for selecting the most valuable data from MR2 to be included in the adaptation via transfer learning.

RESULTS

The proposed method was tested on 20 MR1 and 32 MR2 test sets. Mean ± SD dice similarity coefficients are 0.93 ± 0.04, 0.87 ± 0.03, and 0.80 ± 0.10 on MR1 and 0.94 ± 0.05, 0.88 ± 0.04, and 0.80 ± 0.05 on MR2 for bladder, rectum, and sigmoid, respectively. Hausdorff distances (95th percentile) are 4.18 ± 0.52, 2.54 ± 0.41, and 5.03 ± 1.31 mm on MR1 and 2.89 ± 0.33, 2.24 ± 0.40, and 3.28 ± 1.08 mm on MR2, respectively. The performance of our method is superior to other state-of-the-art segmentation methods.

CONCLUSIONS

We proposed a two-step CNN approach for fully automated segmentation of female pelvic MR bladder, rectum, and sigmoid from T2W MR volume. Our experimental results demonstrate that the developed method is accurate, fast, and reproducible, and outperforms alternative state-of-the-art methods for OAR segmentation significantly (p < 0.05).

Refining Adjuvant Therapy for Endometrial Cancer: New Standards and Perspectives

Endometrial carcinoma is the most frequent cancer of the reproductive female organs. Most endometrial cancers are diagnosed at early stage (75%). Treatment options depend on pathogenetic, histopathologic and clinical characteristic at the diagnosis. To improve patient management in the near future, recent research has focused on new molecular features; evidence has shown that these give a better definition of patient prognosis and can help in tailoring adjuvant treatments by identifying specific subgroups of patients whose tumors may benefit from specific therapeutic approaches. In this review, we will focus on current knowledge of adjuvant treatment of endometrial carcinoma, using a prognostic-risk group stratification based on pathogenetic, clinical and molecular features, and will take a look at the ongoing trials that will further change the therapeutic approach in coming years.

ESGO/ESTRO/ESP guidelines for the management of patients with endometrial carcinoma

A European consensus conference on endometrial carcinoma was held in 2014 to produce multidisciplinary evidence-based guidelines on selected questions. Given the large body of literature on the management of endometrial carcinoma published since 2014, the European Society of Gynaecological Oncology (ESGO), the European SocieTy for Radiotherapy & Oncology (ESTRO) and the European Society of Pathology (ESP) jointly decided to update these evidence-based guidelines and to cover new topics in order to improve the quality of care for women with endometrial carcinoma across Europe and worldwide. ESGO/ESTRO/ESP nominated an international multidisciplinary development group consisting of practicing clinicians and researchers who have demonstrated leadership and expertise in the care and research of endometrial carcinoma (27 experts across Europe). To ensure that the guidelines are evidence-based, the literature published since 2014, identified from a systematic search was reviewed and critically appraised. In the absence of any clear scientific evidence, judgment was based on the professional experience and consensus of the development group. The guidelines are thus based on the best available evidence and expert agreement. Prior to publication, the guidelines were reviewed by 191 independent international practitioners in cancer care delivery and patient representatives. The guidelines comprehensively cover endometrial carcinoma staging, definition of prognostic risk groups integrating molecular markers, pre- and intra-operative work-up, fertility preservation, management for early, advanced, metastatic, and recurrent disease and palliative treatment. Principles of radiotherapy and pathological evaluation are also defined.

Adjuvant vaginal cuff brachytherapy in surgically treated endometrial carcinoma patients - in view of the recent evidence

Vaginal cuff brachytherapy is an essential component of adjuvant post-operative therapy in endometrial carcinoma. Brachytherapy boost, as a part of adjuvant pelvic radiotherapy, including concomitant chemoradiotherapy combined with four cycles carboplatin/paclitaxel chemotherapy, is used in early-stage high-risk and advanced stage disease. This strategy is widely accepted and recommended by international guidelines, despite the fact that combined therapy has never been verified in randomized trials. Brachytherapy alone is the adjuvant treatment of choice for many patients with early-stage endometrial cancer, with high-intermediate features, replacing external beam pelvic radiotherapy. It provides equivalent vaginal control with a lower risk of toxicity, and minimal impact on health-related quality of life. Available evidence did not demonstrate the superiority of sole vaginal brachytherapy combined with three cycles of carboplatin/paclitaxel chemotherapy, over the standard pelvic irradiation for patients with early-stage, high-intermediate-, and high-risk endometrial cancer. This article summarized the available evidence on the role of post-operative vaginal cuff brachytherapy in endometrial cancer patients. Additionally, the risk groups definition, some aspects of brachytherapy technique, and the importance of pathological and molecular risk factors for endometrial cancer risk stratification were presented. Furthermore, the role of brachytherapy according to the European Society of Gynecological Oncology/European Society for Radiotherapy and Oncology/European Society of Pathology 2021 guidelines for the management of patients with endometrial carcinoma was presented.

ESGO/ESTRO/ESP Guidelines for the management of patients with endometrial carcinoma

A European consensus conference on endometrial carcinoma was held in 2014 to produce multidisciplinary evidence-based guidelines on selected questions. Given the large body of literature on the management of endometrial carcinoma published since 2014, the European Society of Gynaecological Oncology (ESGO), the European SocieTy for Radiotherapy & Oncology (ESTRO) and the European Society of Pathology (ESP) jointly decided to update these evidence-based guidelines and to cover new topics in order to improve the quality of care for women with endometrial carcinoma across Europe and worldwide. ESGO/ESTRO/ESP nominated an international multidisciplinary development group consisting of practicing clinicians and researchers who have demonstrated leadership and expertise in the care and research of endometrial carcinoma (27 experts across Europe). To ensure that the guidelines are evidence-based, the literature published since 2014, identified from a systematic search was reviewed and critically appraised. In the absence of any clear scientific evidence, judgment was based on the professional experience and consensus of the development group. The guidelines are thus based on the best available evidence and expert agreement. Prior to publication, the guidelines were reviewed by 191 independent international practitioners in cancer care delivery and patient representatives. The guidelines comprehensively cover endometrial carcinoma staging, definition of prognostic risk groups integrating molecular markers, pre- and intra-operative work-up, fertility preservation, management for early, advanced, metastatic, and recurrent disease and palliative treatment. Principles of radiotherapy and pathological evaluation are also defined.

ESGO/ESTRO/ESP guidelines for the management of patients with endometrial carcinoma

A European consensus conference on endometrial carcinoma was held in 2014 to produce multi-disciplinary evidence-based guidelines on selected questions. Given the large body of literature on the management of endometrial carcinoma published since 2014, the European Society of Gynaecological Oncology (ESGO), the European SocieTy for Radiotherapy and Oncology (ESTRO), and the European Society of Pathology (ESP) jointly decided to update these evidence-based guidelines and to cover new topics in order to improve the quality of care for women with endometrial carcinoma across Europe and worldwide.

Efficacy and Toxicity of Adjuvant Therapies for High-Risk Endometrial Cancer in Stage I-III: A Systematic Review and Network Meta-Analysis

BACKGROUND The use of adjuvant therapy for high-risk endometrial cancer patients (HREC) in International Federation of Gynecology and Obstetrics (FIGO) stage I-III remains debatable. This network meta-analysis was conducted to compare and rank adjuvant therapies based on efficacies and toxicities to facilitate clinical decision-making and further research. MATERIAL AND METHODS We searched 3 databases - PubMed, EMBASE, and the Cochrane Central Register of Controlled Trials - from inception to December 9, 2019. Only randomized controlled trials that compared any of these adjuvant therapies (pelvic radiotherapy, vaginal brachytherapy, chemotherapy, and chemoradiotherapy) with each other or surgery alone were included. The network meta-analysis was performed in a frequentist framework using Stata software 15.0. RESULTS Fourteen RCTs with 5872 participants were eligible. No significant difference between treatments was observed in 5-year overall survival (OS) or distant metastasis. Compared with surgery alone, adjuvant pelvic radiotherapy plus chemotherapy (pelvic RT-CT) prolonged 5-year progression-free survival (PFS) and pelvic radiotherapy (pelvic RT) (RR=0.61, 95% CI 0.39-0.96; RR=0.779, 95% CI 0.63-0.95). Compared with surgery alone, pelvic RT, the combination of pelvic RT and vaginal brachytherapy (pelvic RT-VBT), chemotherapy (CT), and pelvic RT-CT led to fewer local recurrences (RR=0.33, 95% CI 0.21-0.50; RR=0.15, 95% CI 0.03-0.74; RR=0.39, 95% CI 0.21-0.73; RR=0.17, 95% CI 0.06-0.46). Adjuvant CT was found to result in more grade III/IV late toxicities than surgery alone (RR=11.8, 95% CI 1.02-137.14). Pelvic RT-CT ranked first for OS, PFS, distant metastasis, and local recurrence. CONCLUSIONS Pelvic RT-CT is superior to other treatments for PFS and local recurrence rate, and associated related toxicities are tolerable, suggesting it may be an ideal adjuvant therapy for HREC patients.

One-week vaginal brachytherapy schedule as exclusive adjuvant post-operative treatment in intermediate- and high-intermediate-risk endometrial cancer patients

Purpose

The aim of the study was to report survival outcomes and toxicities incidence by using one-week vaginal brachytherapy (VBT) schedule in intermediate- and high-intermediate-risk endometrial cancer patients.

Material and methods

One hundred and eight patients were treated with exclusive high-dose-rate (HDR) brachytherapy short schedule (7 Gy/fraction/every other day/1 week). Acute and late rectal, urinary, and vaginal toxicities were recorded according to radiation therapy oncology group (RTOG) scores and late effects normal tissue task force – subjective, objective, management, analytic (LENT-SOMA) scores, respectively. Overall survival (OS), cause specific survival (CSS), and disease-free survival (DFS) were evaluated.

Results

Median follow-up was 44 months (range, 6-117 months). The 5-year OS, CSS, and DFS rates were 92.7%, 96.4%, and 89.5%, respectively. Seven of 108 (6.5%) patients relapsed after a median time of 31 months (range, 5-56 months). Death occurred in 6 patients. Four patients died for intercurrent causes without an evidence of disease. Acute bladder toxicity G1-G2 was reported in 11 of 108 (10%) patients, vaginal toxicity G1-G2 in 6 of 108 (5.5%), and gastrointestinal toxicity was observed in 3 of 108 (3%) patients. Late bladder and gastrointestinal G1 toxicities were reported in 4 of 108 (4%) and 1 of 108 (1%) patients, respectively. Late vaginal toxicity (G1-G2) was recorded in 3 of 108 (3%) cases. No grade 3-4 bladder, vaginal, and gastrointestinal toxicities were noted.

Conclusions

Exclusive short course adjuvant VBT is an effective treatment in patients with early-stage endometrial cancer and provides good outcomes in terms of disease local control and DFS, with low rates of toxicity profile.

The role of vaginal brachytherapy in stage I endometrial serous cancer: a systematic review

Purpose

Serous adenocarcinoma (uterine serous carcinoma – USC) is a rare and aggressive histologic subtype of endometrial cancer, with a high-rate of recurrence and poor prognosis. The adjuvant treatment for stage I patients is unclear. The purpose of this study was to evaluate the outcomes of stage I USC treated exclusively with chemotherapy plus vaginal brachytherapy (VBT).

Material and methods

A systematic research using PubMed, Scopus, and Cochrane library was conducted to identify full articles evaluating the efficacy of VBT in patients with stage I USC. A search in ClinicalTrials.gov was performed in order to detect ongoing or recently completed trials, and in PROSPERO for searching ongoing or recently completed systematic reviews.

Results

All studies were retrospective and 364 of evaluated patients were found. The average local control was 97.5% (range, 91-100%), the disease free-survival was 88% (range, 82-94%), the overall survival was 93% (range, 72-100%), the specific cancer survival was 89.4% (range, 84.8-94%), and the G3-G4 toxicity was 0-8%.

Conclusions

These data support the concept that in adequately selected patients, VBT alone may be a suitable radiotherapy technique in women with stage I USC who underwent surgical staging and received adjuvant chemotherapy.

Impact of different adjuvant radiotherapy modalities on women with early-stage intermediate- to high-risk endometrial cancer

OBJECTIVE

Vaginal brachytherapy was recommended for patients with intermediate-risk endometrial cancer, however, optimal radiotherapy modalities for intermediate-high- or high-risk patients remains controversial. Previous studies have mainly focused on survival outcomes and have seldom taken cost issues into consideration, especially for high-risk patients. The purpose of this study is to compare the survival outcomes and costs associated with two adjuvant radiotherapy modalities in the management of patients with early-stage, intermediate- to high-risk endometrial cancer.

METHODS

According to ESMO-ESCO-ESTRO criteria, 238 patients with stage I/II, intermediate- to high-risk endometrial cancer who underwent radiotherapy from January 2003 to December 2015 at our institution were reviewed. The vaginal brachytherapy group and external beam radiation therapy combined with the vaginal brachytherapy group were propensity score-matched at a 1:1 ratio. The Kaplan-Meier method and Cox proportional hazards regression model were used.

RESULTS

A total of 361 patients met our inclusion criteria, the median age of the patients was 58 years (range, 28-85). All were diagnosed with stage I-II endometrial cancer (324 with stage I and 37 with stage II; 350 with endometrioid adenocarcinoma; and 10 with mucinous carcinoma). The median follow-up time was 60.5 months (range, 3-177). Among 119 matched pairs, no significant differences were found in overall (10.9% vs 8.4%, P=0.51), locoregional (4.2% vs 1.7%, P=0.45), or distant recurrence rates (6.7% vs 6.7%, P=1.0) between the two groups. There were also no differences in the 5-year overall (94.8% vs 93.9%, P=0.78) or progression-free survival (90.0% vs 84.4%, P=0.23) between the two groups. The rates of acute and late toxicity were significantly higher in the external beam radiation therapy combined with vaginal brachytherapy vs the vaginal brachytherapy group (all P<0.05), except for the acute hematological toxicity rate (17.6% vs 9.2%, P=0.06). External beam radiation therapy combined with vaginal brachytherapy had a higher median cost ($2759 vs $937, P<0.001) and longer median radiotherapy duration (41 days vs 17 days, P<0.001) than vaginal brachytherapy.

CONCLUSION

Vaginal brachytherapy was associated with similar local control and long-term survival outcomes relative to the combination of external beam radiotherapy and vaginal brachytherapy and it also minimizes radiation-related complications, reduces medical costs, and shortens radiotherapy duration. Vaginal brachytherapy may be the optimal radiation modality for patients with early-stage endometrial cancer at intermediate to high risk.

The Effect of Prognostic Factors and Adjuvant Radiotherapy on Survival in Patients with High-Grade Early-Stage Endometrial Cancer: A Retrospective Clinical Study

BACKGROUND This retrospective clinical study aimed to investigate the effect of prognostic factors and adjuvant radiotherapy in patients with high-grade early-stage endometrial cancer on overall survival (OS) and disease-free survival (DFS). MATERIAL AND METHODS The medical records of patients diagnosed with high-grade, early stage (I or II) endometrial adenocarcinoma who had received adjuvant radiotherapy after surgery were reviewed. RESULTS Seventy-nine patients included 39 patients (49.4%) with stage II endometrial cancer, 25 patients (31.6%) with histologic grade 3 tumors, and 47 patients (59.5%) with endometrial cancer showing lymphovascular space invasion (LVSI). There were 45 patients (57.0%) who received external pelvic radiotherapy with an average dose of 46.0 Gy (range, 11.2-50.4 Gy), and 34 patients (43.0%) received vaginal brachytherapy (VBT) with an average dose of 21.5 Gy (range, 10-36 Gy). Multivariate analysis showed that tumor stage (HR, 4.066; 95% CI, 1.227-13.467; p=0.022) and histologic grade (HR, 16.652; 95% CI, 4.430-62.589; p<0.001) were independent predictors for OS. Increased serum CA-125 levels (HR, 1.136; 95% CI, 0.995-1.653; p=0.047) and histologic grade (HR, 3.236; 95% CI, 1.107-15.156; p=0.015) were independent predictors for DFS. Adjuvant radiotherapy was not found to be significantly associated with improved OS (HR, 1.259; 95% CI, 0.518-3.058; p=0.612) or DFS (HR, 1.056; 95% CI, 0.994-1.123; p=0.078). CONCLUSIONS This retrospective study showed that in high-grade early-stage endometrial cancer treated with postoperative adjuvant radiotherapy, independent predictors for OS were tumor stage and grade. Adjuvant radiotherapy was not associated with improved OS or DFS.

Vaginal toxicity after high-dose-rate endovaginal brachytherapy: 20 years of results

Purpose

To evaluate vaginal toxicity (primary endpoint) and local control (secondary endpoint) in patients with endometrial cancer who underwent primary surgery and adjuvant high-dose-rate (HDR) endovaginal brachytherapy (BT).

Material and methods

In September 2017, the authors conducted a comprehensive literature search of the following electronic databases: PubMed, Web of Science, Scopus, and Cochrane library. In this systematic review, the authors included randomized trials, non-randomized trials, prospective studies, retrospective studies, and cases. The time period of the research included articles published from September 1997 to September 2017.

Results

Acute endovaginal toxicity occurred in less than 20.6% and all acute toxicities were G1-G2. The most common early side effects due to HDR-BT treatment were vaginal inflammation, vaginal irritation, dryness, discharge, soreness, swelling, and fungal infection. G1-G2 late toxicity occurred in less than 27.7%. Finally, G3-G4 late vaginal occurred in less than 2%. The most common late side effects consisted of vaginal discharge, dryness, itching, bleeding, fibrosis, telangiectasias, stenosis, short or narrow vagina, and dyspareunia.

Conclusions

The data suggest that HDR endovaginal brachytherapy, with or without chemotherapy, is very well tolerated with low rates of acute and late vaginal toxicities. Further prospective studies with higher numbers of patients and longer follow-up are necessary to evaluate acute and late toxicities after HDR endovaginal brachytherapy.