Clinical outcomes of definitive chemoradiation followed by intracavitary pulsed-dose rate image-guided adaptive brachytherapy in locally advanced cervical cancer

Theragnostic Gadolinium-Based Nanoparticles Safely Augment X-ray Radiation Effects in Patients with Cervical Cancer

Activated guided irradiation by X-ray (AGuIX) nanoparticles are gadolinium-based agents that have the dual benefit of mimicking the effects of a magnetic resonance imaging (MRI) contrast agent used in a clinical routine and enhancing the radiotherapeutic activity of conventional X-rays (for cancer treatment). This "theragnostic" action is explained on the one hand by the paramagnetic properties of gadolinium and on the other hand by the generation of high densities of secondary radiation following the interaction of ionizing radiation and high-Z atoms, which leads to enhanced radiation dose deposits within the tumors where the nanoparticles accumulate. Here, we report the results of a phase I trial that aimed to assess the safety and determine the optimal dose of AGuIX nanoparticles in combination with chemoradiation and brachytherapy in patients with locally advanced cervical cancer. AGuIX nanoparticles were administered intravenously and appropriately accumulated within tumors on a dose-dependent manner, as assessed by T1-weighted MRI, with a rapid urinary clearance of uncaught nanoparticles. We show that the observed tumor accumulation of the compounds can support precise delineation of functional target volumes at the time of brachytherapy based on gadolinium enhancement. AGuIX nanoparticles combined with chemoradiation appeared well tolerated among the 12 patients treated, with no dose-limiting toxicity observed. Treatment yielded excellent local control, with all patients achieving complete remission of the primary tumor. One patient had a distant tumor recurrence. These results demonstrate the clinical feasibility of using theranostic nanoparticles to augment the accuracy of MRI-based treatments while focally enhancing the radiation activity in tumors.

Radiation Proctitis in Patients With Locally Advanced Cervical Cancer Treated by Chemoradiation: Analysis and Predictive Factors From a Retrospective Cohort

OBJECTIVES

Radiation proctitis is a misunderstanding complication of chemoradiation in locally advanced cervical cancer. The objective of our study is to provide a detailed description and analysis of predictive factors associated with radiation proctitis in a retrospective cohort of patients treated by chemoradiation for locally advanced cervical cancer.

METHODS

All patients treated by exclusive chemoradiation or chemoradiation followed by brachytherapy for locally advanced cervical cancer from 2011 to 2017 were included in the study. A bivariate analysis was conducted to establish correlations between the occurrence of radiation proctitis and various clinical and technical variables.

RESULTS

A total of 128 patients were included in the study. The mean dose (SD) to the planning target volume was 47.1 Gy (6.2). Fifty-nine (46.1%) patients underwent brachytherapy. Sixteen patients (12.5%) developed radiation proctitis, grade 2 or higher in 12 patients (9.3%). In univariate analysis, anticoagulant or antiplatelet treatments ( P =0.039), older age ( P =0.049), rectal volume irradiated at 40 Gy ( P =0.01) and 30 Gy ( P =0.037) were significantly associated with the occurrence of a grade ≥2 radiation proctitis. The delivered dose to 2 cm 3 of rectum (D2cm 3 ) showed a potential association with the occurrence of radiation proctitis of all grades ( P =0.064).

CONCLUSIONS

This study highlights clinical and technical factors that should be considered in assessing the risk of radiation proctitis. These results contribute to a better understanding of this complication.

Monocentric Retrospective Study: Efficacy, Feasibility, and Prognostic Factors of Single-Insertion High-Dose-Rate Brachytherapy With 4 Sessions for Locally Advanced Cervical Cancer

Purpose

This study aims to assess the feasibility and efficacy of high-dose rate (HDR) brachytherapy (BT) administered in a single insertion with 4 treatment sessions for locally advanced cervical cancer and to identify the prognostic factors influencing outcomes.

Methods and Materials

We retrospectively analyzed the clinical data of patients with cervical cancer with locally advanced disease (International Federation of Gynecology and Obstetrics 2018 IB-IVB) treated at our institution from January 2014 through December 2021. Each patient received definitive radiation therapy with an external irradiation dosage between 45 and 50.4 Gy along with concurrent chemotherapy. HDR-BT (24 Gy) was prescribed to a high-risk clinical target volume.

Results

One hundred thirty-nine patients were included and the HDR-BT program could be fully performed in 136 patients (98%). Over a median follow-up duration of 40.5 months, the 2-year local control (LC), overall survival (OS), and disease-free survival rates stood at 79.4%, 77.7%, and 61.7%, respectively, with 5-year rates at 78.2%, 61.6%, and 55.7%. Multivariate analysis revealed the primary determinant of LC as the tumor's response to external beam radiation therapy as determined via magnetic resonance imaging before BT. Parametrial involvement demonstrated a significant multivariate association with disease-free survival (P = .04). Regarding OS, parametrial invasion (P = .01) and the tumor's response postchemoradiotherapy (P = .02) emerged as significant factors. Regarding chronic toxicities, 18% (25 patients) experienced grade 3 complications. An optimal D2 cc (bowel) threshold of 70 Gy (P = .001) was identified to limit chronic digestive complications of grade 3 or higher.

Conclusions

The implementation of single-insertion, 4-session HDR-BT could be performed in 98% of the patients. It yields favorable LC and OS rates, coupled with tolerable toxicity in patients with locally advanced cervical cancer. Response to initial chemoradiotherapy evaluated on pre-BT magnetic resonance imaging is an important prognostic factor and could help to individualize therapeutic strategies.

The current state and future perspectives of radiotherapy for cervical cancer

Radiotherapy is an effective treatment method for cervical cancer and is typically administered as external beam radiotherapy followed by intracavitary brachytherapy. In Japan, center shielding is used in external beam radiotherapy to shorten treatment time and reduce the doses delivered to the rectum or bladder. However, it has several challenges, such as uncertainties in calculating the cumulative dose. Recently, external beam radiotherapy has been increasingly performed with intensity-modulated radiotherapy, which reduces doses to the rectum or bladder without center shielding. In highly conformal radiotherapy, uncertainties in treatment delivery, such as inter-fractional anatomical structure movements, affect treatment outcomes; therefore, image-guided radiotherapy is essential for appropriate and safe performance. Regarding intracavitary brachytherapy, the use of magnetic resonance imaging-based image-guided adaptive brachytherapy is becoming increasingly widespread because it allows dose escalation to the tumor and accurately evaluates the dose delivered to the surrounding normal organs. According to current evidence, a minimal dose of D90% of the high-risk clinical target volume is significantly relevant to local control. Further improvements in target coverage have been achieved with combined interstitial and intracavity brachytherapy for massive tumors with extensive parametrical involvement. Introducing artificial intelligence will enable faster and more accurate generation of brachytherapy plans. Charged-particle therapies have biological and dosimetric advantages, and current evidence has proven their effectiveness and safety in cervical cancer treatment. Recently, radiotherapy-related technologies have advanced dramatically. This review provides an overview of technological innovations and future perspectives in radiotherapy for cervical cancer.

Clinical transfer of AGuIX®-based radiation treatments for locally advanced cervical cancer: MR quantification and in vitro insights in the NANOCOL clinical trial framework

Clinical trials incorporating metallic nanoparticles (NPs) have recently begun. Radiotherapy planning does not take into account NPs concentrations observed in the patients' target volumes. In the framework of the NANOCOL clinical trial including patients treated for locally advanced cervical cancers, this study proposes a complete method to evaluate the radiation-induced biological effects of NPs. For this, calibration phantom was developed and MRI sequences with variable flip angles were acquired. This process allowed the quantification of NPs in the tumor of 4 patients, which was compared to the results of mass spectrometry obtained from 3 patient biopsies. The concentration of the NPs was reproduced in 3D cell models. Based on clonogenic assays, the radio-enhancement effects were quantified for radiotherapy and brachytherapy, and the impact in terms of local control was evaluated. T₁ signal change in GTVs revealed NPs accumulation ~12.4 μmol/L, in agreement with mass spectrometry. Radio-enhancement effects of about 15 % at 2 Gy were found for both modalities, with a positive impact on local tumor control. Even if further follow-up of patients in this and subsequent clinical trials will be necessary to assess the reliability of this proof of concept, this study opens the way to the integration of a dose modulation factor to better take into account the impact of NPs in radiotherapy treatment.

Galalae R. Ultrasound-Guided Brachytherapy for Cervical Cancer - A Tool for Quality Improvement in Brachytherapy?

Nowadays, brachytherapy is one of the major components to treat inoperable cervical cancer. Brachytherapy yields a higher dose to the target (cervix) while sparing normal tissues. Developments of brachytherapy stepped forward in the previous decade by image-guided brachytherapy (IGBT) turning brachytherapy from point-based planning to volume-based planning and IGBT improves the treatment quality for cervical cancer. Magnetic resonance imaging (MRI) or computed tomography (CT) is utilized in brachytherapy and showed promising results internationally. However, in a limited-resource area, the implementation of IGABT is difficult due to many causes (manpower, equipment, or budgets). To improve the quality in limited resources, ultrasound is introduced. The utilization of ultrasound in brachytherapy practice is to prevent uterine perforation during application. With present data, measurement by ultrasound showed the correlation to MRI measurement in uterine dimensions. With these aspects, there are many researches using ultrasound to improve the quality of treatment in brachytherapy, for example, to guide contouring on CT or to support brachytherapy planning. The use of ultrasound improves the quality of brachytherapy in comparison to conventional planning and supports the improvement in brachytherapy for cervical cancer.

Survival outcome of cervical cancer patients treated by image-guided brachytherapy: a 'real world' single center experience in Thailand from 2008 to 2018

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.

Prophylactic extended-field irradiation for locally advanced cervical cancer

Concomitant chemoradiotherapy is the standard treatment for locally advanced cervical cancer. Pelvic irradiation is commonly recommended for patients with negative para-aortic lymph nodes(PALNs). However, owing to the development of imaging-guided brachytherapy, distant failure has become the main failure pattern. The PALNs are a vital site of distant metastasis, and the para-aortic region may contain occult microscopic metastases that are barely detected owing to imaging technology restriction. The prognostic of patients who experienced PALN failure is dismal. Typically, there are four ways to decrease PALN failure. First, surgical staging can be performed to assess the occurrence of metastasis in the para-aortic region; however, the application of surgical staging is decreasing owing to controversial survival benefits and accompanying complications of surgery. Second, regular imaging surveillance and timely salvage of early recurrences could reduce PALN failure. Third, better systemic adjuvant therapy could be recommended since it has enormous potential to reduce distant metastases and improve overall survival. Fourth, performing prophylactic extended-field irradiation (EFI), including pelvic and para-aortic region irradiation, can sterilize occult microscopic metastases in the para-aortic region and improve survival. Prior investigations have revealed that prophylactic EFI could reduce PALN failure as well as distant metastasis and present the benefit of survival. Yet, owing to the serious morbidity induced by enlarged irradiation field in the era of conventional irradiation techniques, further research on EFI is stagnated. Nowadays, with the development of new technologies, intensity modulated radiation therapy can deliver a higher dose to tumors with acceptable toxicity. Prophylactic EFI regained attention. However, the inclusion criteria of prophylactic EFI in existing studies reveal great discrepancies. Thus, it is urgent to precisely identify indications for better survival and lower complications in patients with cervical cancer. In this review, we identify indications and summary guidelines for prophylactic EFI, which may provide a foundation for further trials and clinical applications.

Four-Dimensional Image-Guided Adaptive Brachytherapy for Cervical Cancer: A Systematic Review and Meta-Regression Analysis

Purpose

The ICRU/GEC-ESTRO released the ICRU Report No. 89, which introduced the concept of four-dimensional brachytherapy and ushered in a new era of brachytherapy for cervical cancer. The purpose of this study was to evaluate the local control and late toxicity of four-dimensional brachytherapy in cervical cancer through a systematic review and to reveal the dose-response relationship between the volumetric dose paraments and the local control rate via a probit model.

Material and Methods

We identified studies that reported the HR-CTV D90 and local control probabilities by searching the PubMed Database, the Web of Science Core Collection and the Cochrane Library Database through February 1st, 2022. Regression analyses were performed between the HR-CTV D90 and the local control probability using a probit model.

Results

Nineteen studies enrolling 3,616 patients were included. The probit model showed a significant relationship between the HR-CTV D90 value and IR-CTV D90 Vs. the local control probability, P < 0.001 and P = 0.003, respectively. The D90 for HR-CTV and IR-CTV corresponding to a probability of 90% local control was 79.1 GyEQD2,10 (95% CI:69.8 – 83.7 GyEQD2,10) and 66.5 GyEQD2,10 (95% CI: 62.8 - 67.9 GyEQD2,10), respectively. The limits for the prescribed dose of 85 GyEQD2,10 for HR-CTV D90 theoretically warranted a 92.1% (95% CI: 90.2% - 95.3%) local control rate, and 87.2% (95% CI: 82.4% - 91.8%) local control probability was expected for 65 GyEQD2,10 to IR-CTV D90. The probit model showed no significant relationship between the D2cc to organs at risk and the probability of grade 3 and above gastrointestinal or genitourinary toxicity.

Conclusions

Four-dimensional brachytherapy takes into account uncertain factors such as tumour regression, internal organ motion and organ filling, and provides a more accurate and more therapeutic ratio delivery through adaptive delineation and replanning, replacement of the applicator, and the addition of interstitial needles. The dose volume effect relationship of four-dimensional brachytherapy between the HR-CTV D90 and the local control rate provides an objective planning aim dose.

Prognostic factors of dose-response relationship for nodal control in metastatic lymph nodes of cervical cancer patients undergoing definitive radiotherapy with concurrent chemotherapy

Objective

Regional control is occasionally unsatisfactory in cervical cancer, with the optimal radiation dose for nodal metastases in definitive radiotherapy (RT) with concurrent chemotherapy (CRT) remaining controversial. We investigated dose-response relationship for nodal local control in cervical cancer.

Methods

We identified 115 patients with 417 metastatic nodes who received definitive CRT for cervical cancer with nodal metastases. External beam radiation therapy and brachytherapy plans were summated to determine total dose received by each node. Prognostic factors of nodal control and dose-response relationship were investigated using Cox-regression and restricted cubic spline function.

Results

The 2-year progression-free survival rate was 69.4%. Among 43 patients with failures, 17 patients (37.5%) had regional failure included in first failure sites of which all except one were in-field only regional failures. Total 30 nodes showed recurrence at initial metastatic site after treatment. Neutrophil-to-lymphocyte ratio (NLR) ≥3.1, total radiation dose (minimum dose received by 98% of the target volume in equivalent dose in 2 Gy per fractions), and initial nodal volume ≥5.29 mL were poor prognostic factors (all p<0.050) of nodal local control. Restricted cubic spline functions revealed strongest dose-response relationship in high NLR (NLR ≥3.1) and initial nodal volume ≥5.29 mL subgroup.

Conclusion

Initial nodal volume, radiation dose_, and NLR were significant factors of nodal local control in cervical cancer; a stronger dose-response relationship was seen in bulky nodes with high NLR. Clinicians may consider these factors when determining the RT dose and the need for boost to nodal metastases in cervical cancer.

One-third of cervical cancer with nodal metastases had regional failure as first failure, mostly in-field failures. Neutrophil-to-lymphocyte ratio (NLR) ≥3.1, radiation dose, and initial nodal volume ≥5.29 mL were significant factors of nodal control. The strongest radiation dose-response was found in bulky nodes with a high NLR.

Clinical outcomes after positron emission tomography/computed tomography-based image-guided brachytherapy for cervical cancer

INTRODUCTION

Although positron-emission tomography (PET) plays an integral role in cervix cancer diagnosis, there are limited data on PET-based image-guided brachytherapy (IGBT). We aimed to report the long-term outcomes of PET-based IGBT.

METHODS

We reviewed 151 patients treated with definitive radiotherapy (RT), including PET-based IGBT between 2009 and 2018. After median 45 Gy of external beam RT with the four-field technique, a median 24 Gy of high-dose-rate iridium-192 IGBT was delivered in six fractions with Fletcher-Suit tandem and ovoids. All patients underwent 18F-fluorodeoxyglucose-PET/computed tomography planning with a brachytherapy applicator. Multivariable analysis of local control (LC) was performed using Cox regression analysis.

RESULTS

The median high-risk clinical target volume (HRCTV) and HRCTV D90% were 51.8 (interquartile range [IQR] 35.9-79.4) cm³ and 77.7 (IQR 74.7-81.2) Gy, respectively. With a median follow-up of 57 (IQR 24.3-81.4) months, the 5-year LC rate was 89.2%. HRCTV ≥72 cm³ was associated with inferior LC (hazard ratio, 3.72, p = .017) after multivariable analysis: the 5-year LC rates were 94.0% and 77.9% for HRCTVs ≥72 and < 72 cm³ , respectively (p = .002). The impact of HRCTV D_90% ≥70 Gy on LC was significant in patients with an HRCTV ≥72 cm³ compared to that in those with HRCTV < 72 cm³ . Patients with adeno/adenosquamous carcinoma demonstrated inferior LC in both groups. There were 13 (8.6%) and 11 (7.3%) patients with acute and late severe toxicities after RT.

CONCLUSION

PET-based IGBT leads to favorable LC, and HRCTV ≥72 cm³ requires further dose escalation to improve outcomes.

High-dose-rate brachytherapy boost for locally advanced cervical cancer: Oncological outcome and toxicity analysis of 4 fractionation schemes

PURPOSE

Brachytherapy (BT) boost after radio-chemotherapy (RCT) is a standard of care in the management of locally advanced cervical cancer (LACC). As there is no consensus on high-dose-rate (HDR) BT fractionation schemes, our aim was to report the oncological outcome and toxicity profile of four different schemes using twice-a-day (BID) HDR-BT.

PATIENTS AND METHODS

This was an observational, retrospective, single institution study for patients with LACC receiving a HDR-BT boost. The latter was performed with a single implant and single imaging done on day 1. The different fractionation schemes were: 7 Gy + 4x3.5 Gy (group 1); 7 Gy + 4x4.5 Gy (group 2); 3x7Gy (group 3) and 3x8Gy (group 4). Local (LFS), nodal (NFS) and metastatic (MFS) recurrence-free survival as well as progression-free survival (PFS) and overall survival (OS) were analyzed. Acute (≤6 months) and late toxicities (>6 months) were reported.

RESULTS

From 2007 to 2018, 191 patients were included. Median follow-up was 57 months [45-132] and median EQD210D90CTVHR was 84, 82 and 90 Gy for groups 2, 3 and 4 respectively (dosimetric data missing for group 1). The 5-year LFS, NFS, MFS, PFS and OS were 85% [81-90], 83% [79-86], 70% [67-73], 61% [57-64] and 75% [69-78] respectively, with no significant difference between the groups. EQD210D90CTVHR < 85 Gy was a prognostic factor for local recurrence in univariate analysis (p = 0.045). The rates of acute/late grade ≥ 2 urinary, digestive and gynecological toxicities were 9%/15%, 3%/15% and 9%/25% respectively.

CONCLUSION

Bi-fractionated HDR-BT boost seems feasible with good oncological outcome and slightly more toxicity after dose escalation.

Deep-learning-assisted algorithm for catheter reconstruction during MR-only gynecological interstitial brachytherapy

Magnetic resonance imaging (MRI) offers excellent soft‐tissue contrast enabling the contouring of targets and organs at risk during gynecological interstitial brachytherapy procedure. Despite its advantage, one of the main obstacles preventing a transition to an MRI‐only workflow is that implanted plastic catheters are not reliably visualized on MR images. This study aims to evaluate the feasibility of a deep‐learning‐based algorithm for semiautomatic reconstruction of interstitial catheters during an MR‐only workflow. MR images of 20 gynecological patients were used in this study. Note that 360 catheters were reconstructed using T1‐ and T2‐weighted images by five experienced brachytherapy planners. The mean of the five reconstructed paths were used for training (257 catheters), validation (15 catheters), and testing/evaluation (88 catheters). To automatically identify and localize the catheters, a two‐dimensional (2D) U‐net algorithm was used to find their approximate location in each image slice. Once localized, thresholding was applied to those regions to find the extrema, as catheters appear as bright and dark regions in T1‐ and T2‐weighted images, respectively. The localized dwell positions of the proposed algorithm were compared to the ground truth reconstruction. Reconstruction time was also evaluated. A total of 34 009 catheter dwell positions were evaluated between the algorithm and all planners to estimate the reconstruction variability. The average variation was 0.97 ± 0.66 mm. The average reconstruction time for this approach was 11 ± 1 min, compared with 46 ± 10 min for the expert planners. This study suggests that the proposed deep learning, MR‐based framework has potential to replace the conventional manual catheter reconstruction. The adoption of this approach in the brachytherapy workflow is expected to improve treatment efficiency while reducing planning time, resources, and human errors.

Comparative dosimetry of brachytherapy treatment planning between a volume-based plan by CT and a point-based plan by TAUS in CT datasets for brachytherapy

Aim:

To evaluate comparative dosimetry of brachytherapy treatment planning between a volume-based plan by computed tomography (CT) and a point-based plan by transabdominal ultrasound (TAUS) in CT datasets for brachytherapy.

Materials and methods:

From 2019 to 2021, 59 different datasets of CT images were collected from 38 patients treated by intracavitary brachytherapy with tandem ovoid or tandem ring applicators. At that time, TAUS was performed to prevent uterine perforation and to evaluate topography of the cervix during application. In volume-based planning by CT, the target dose was used to keep the dose at 90% of high-risk clinical target volume (HR-CTV), to give a dose of at least 7Gy, while in the point-based plan by TAUS, the target dose was used to keep the minimum dose to eight cervix reference points (measured by TAUS), to give a dose of at least 7Gy. The doses to targets and organs at risk were evaluated and compared between volume-based planning by CT and the point-based plan by TAUS.

Results:

Of 59 fractions, a tandem ovoid applicator was used in 48 fractions (81·3%). In the volume-based plan by CT, the mean doses to HR-CTV(D90), intermediate-risk clinical target volume (IR-CTV)(D90), bladder(D2cc), rectum(D2cc) and sigmoid colon(D2cc) were 7·0, 3·9, 4·9, 2·9 and 3·3 Gy, respectively, while in the point-based plan by TAUS, the mean doses to HR-CTV(D90), IR-CTV(D90), bladder(D2cc), rectum(D2cc) and sigmoid colon(D2cc) were 8·2, 4·6, 5·9, 3·4 and 3·9 Gy, respectively. The percentages of mean dose differences between TAUS and CT of HR-CTV(D90), IR-CTV(D90), bladder(D2cc), rectum(D2cc) and sigmoid colon(D2cc) were 17·7, 19·5, 20·5, 19·5, 21·3 and 19·8%, respectively. With the target dose to the point-based plan by TAUS (7 Gy to the cervix reference points), this was close to D98 of HR-CTV with a mean percentage of difference of 0·6%.

Findings:

The point-based plan by TAUS showed higher values to targets and organs at risk than the volume-based plan by CT. With the point-based plan by TAUS, it was close to D98 of HR-CTV.

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 (NF_PAO) 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 NF_PAO 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 NF_PAO (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 NF_PAO (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 NF_PAO, particularly in patients with nodal disease in the 'small pelvis' and/or CI region at time of diagnosis.

Intra-fractional dosimetric analysis of image-guided intracavitary brachytherapy of cervical cancer

Background

To assess the intra-fractional dosimetric variations of image-guided brachytherapy of cervical cancer.

Methods

A total of 38 fractions (9 patients) undergoing brachytherapy for cervical cancer underwent a CT scanning for treatment planning (planning CT) and a Cone-beam CT (CBCT) scanning immediately prior to delivery (pre-delivery CBCT). The variations of volumes as well as the dosimetric impact from treatment planning to delivery (intra-application) were evaluated. The dose volume histogram parameters including volume, D90 of high-risk clinical target volume (HRCTV) and D2cc of organs at risk (OARs) were recorded.

Results

The relative differences (mean ± 1SD) of the volume and D90 HRCTV across the two scans were − 2.0 ± 3.3% and − 1.2 ± 4.5%, respectively. The variations of D2cc for bladder, rectum, sigmoid and small intestine are − 0.6 ± 17.1%, 9.3 ± 14.6%, 7.2% ± 20.5% and 1.5 ± 12.6%, respectively. Most of them are statistically nonsignificant except the D2cc for rectum, which showed a significant increase (P = 0.001). Using 5% and 10% uncertainty of physical dose for HRCTV at a 6 Gy × 5 high-dose-rate schedule, the possibility of total equivalent doses in 2 Gy fractions (EQD2) lower than 85 Gy is close to 0% and 3%, respectively. Performing similar simulation at 15% and 20% uncertainty of a 4 Gy physical dose for OARs, the possibility of total EQD2 dose exceeding 75 Gy is about 70%. Less than 1% of the total EQD2 of OARs would exceed 80 Gy.

Conclusions

Average intra-fractional dosimetric variation of HRCTV was small in an interval of less than 1 h, and the possibility of total EQD2 exceeding 85 Gy is higher than 97%. The intra-fractional dosimetric variations of OARs might result in an overdose for OARs in a single fraction or the whole treatment. It is necessary to detect unfavorable anatomical changes by re-imaging and take interventions to minimize applied doses and reduce the risk of complications.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13014-021-01870-x.

Advances in External Beam Radiation Therapy and Brachytherapy for Cervical Cancer

The standard of care for the definitive treatment of locoregionally advanced cervical cancer is external beam radiation therapy (EBRT) with concurrent chemotherapy followed by a brachytherapy boost. Historically, EBRT was delivered via a two-dimensional technique based primarily on bony landmarks. This gave way to three-dimensional conformal radiation therapy, which allows for dose calculation and adjustment based on individual tumour and patient anatomy. Further technological advances have established intensity-modulated radiation therapy (IMRT) as a standard treatment modality, given the ability to maintain tumoricidal doses to target volumes while reducing unwanted radiation dose to nearby critical structures, thereby reducing toxicity. Routine image guidance allows for increased confidence in patient alignment prior to treatment, and the ability to visualise the daily position of the targets and organs at risk has been instrumental in allowing safe reductions in treated volumes. Additional EBRT technologies, including proton therapy and stereotactic body radiation therapy, may further improve the therapeutic index. In the realm of brachytherapy, a shift from point-based dose planning to image-guided brachytherapy has been associated with improved local control and reduced toxicity, with additional refinement ongoing. Here we will discuss these advances, the supporting data and future directions.

Impact of transitioning to an online course - A report from the ESTRO gyn teaching course

Introduction

In 2020, the ESTRO course on image-guided radiotherapy and chemotherapy in gynaecological cancer was converted into an online version due to the COVID-19 pandemic. This paper describes the change process and evaluates the impact on participants compared with previous live courses.

Methods and materials

The 2019 live course contained 41 h of educational content, comprising 33 h of synchronous activities (lectures, interactive activities, videos) and 8 h of homework (contouring, dose planning). For the online course, the lectures were provided as pre-course material (11 mandatory, 22 optional). Contouring/dose planning homework was unchanged. The synchronous sessions were reconfigured as six 2-hour webinars (total educational content ~38 h).Participant numbers/characteristics, engagement and satisfaction for six live courses and the online course were compared.

Results

Participant numbers for the online and live courses were similar (90 vs. mean 96). There were more participants from outside Europe (28% vs. mean 18%) and more non-doctors (47% vs. mean 33%). Proportion of participants responding to the pre-course questionnaire was similar (77% vs. mean 78%) but post-course questionnaire response was lower (62% vs. mean 92%).43% participants viewed ≥75% of mandatory lectures before the webinars. 86% viewed the optional lectures. Submissions of contouring and dose planning homework was higher (contouring 77%-90% vs. 56%-69%, dose planning 74%-89% vs. 29%-57%).96% (47/49) participants rated the online course as Excellent (43%) or Good (53%). Overall satisfaction was similar (4.4 vs. mean 4.6).

Conclusion

Participant satisfaction and engagement with the online course remained high despite less contact time with faculty.

MRI-Directed Brachytherapy for Cancer of the Uterine Cervix: A Case Report, Review, and Perspective on the Importance of Widespread Use of This Technological Advance in the United States

Cervical cancer remains a major health challenge in the United States (US), especially among the low socioeconomic and African American populations. The demographics of Mississippi constitute a relatively high percentage of this high-risk population. External beam radiation therapy (EBRT) combined with concurrent chemotherapy and followed by brachytherapy is the gold standard of treatment for stage IB3 through IVA cervical cancer. Arguably, brachytherapy is the most important component of this treatment process. Patterns of Care studies (PCS) and other more recent studies have shown that brachytherapy cannot be omitted or replaced by conventional or image-guided EBRT. The last decade has witnessed the expanding use of image-guided brachytherapy (IGBT). Studies have established the superiority of IGBT over point-based brachytherapy. MRI is associated with superior soft tissue definition compared with CT and is emerging as the new standard of care. The Gynaecological Groupe Européen de Curiethérapie and the European Society for Radiotherapy and Oncology [(GYN) GEC-ESTRO] have recommended that the dose be prescribed to the high-risk clinical target volume (HR-CTV). This volume includes residual tumor present at the time of brachytherapy, the cervix, and any gray areas seen on the scan. The (GYN) GEC-ESTRO has shown that a dose of >8500 cGy delivered in <50 days results in an approximate 10% increase in pelvic control (PC), disease-specific survival, and overall survival (OS) compared to historical controls. The normal tissue toxicity is comparable or better than historical controls as well. This dose, while maintaining normal tissue constraints, may only be achievable with a hybrid intracavitary/interstitial (IC/IS) needle device guided by MRI-based targeting. 

The University of Mississippi Medical Center (UMMC) has initiated an MRI-based cervical brachytherapy program and has treated 18 patients to date; our experience confirms the above findings. In this report, we propose that MRI guidance is necessary and a hybrid IC/IS needle device is required to achieve adequate dose coverages.

Five-fraction HDR brachytherapy in locally advanced cervical cancer: A monocentric experience

PURPOSE

The 5-fraction scheme (5×5-5.5Gy) is a common High-Dose Rate (HDR) intracavitary brachytherapy regimen for locally advanced cervical cancer (LACC). Yet, its equivalence with Pulse-Dose rate (PDR) schemes remains unproved. The present study aimed at reporting on the outcome of LACC patients treated with 5-fraction HDR brachytherapy.

MATERIALS AND METHODS

The medical records of all consecutive patients treated with curative-intent HDR brachytherapy for a LACC in a French Cancer Center were retrospectively reviewed.

RESULTS

Thirty-eight LACC patients underwent a 5-fraction intracavitary HDR brachytherapy between 2015 and 2019 (median dose=25Gy/5 fractions, following external-beam radiotherapy). Median age at diagnosis was 60 (range: 29-87). Thirty-one patients (81.5%) underwent concurrent chemotherapy. Tumor stages ranged from 3 IB2 (7.8%), 4 IB3 (10.5%), 4 IIA2 (10.5%), 12 IIB (31.7%), 1 IIIA (2.6%), 2 IIIB (5.3%), 7 IIIC1 (18.5%), 4 IIIC2 (10.5%), 1 IVA (2.6%) (2018 FIGO). Median D90% to CTV_HR reached 79.5Gy (EQD2). Median D90% to CTV_IR reached 59.5Gy (EQD2). Median Bladder D2cc was 69.8Gy (EQD2). Median Rectum D2cc was 58.3Gy (EQD2). Acute/late grade 3 toxicity was reported in one patient (2.6%). No grade 4-5 toxicity occurred. At a median 38 months follow-up, 10 patients (26.3%) had local (n=7, 18.4%), nodal (n=6, 15.7%) and/or distant (n=7, 18.4%) relapse. Three-year overall survival rate was of 81.6%.

CONCLUSION

The 5-fraction HDR scheme was well tolerated even in frail patients. Three-year local control was lower than expected. Treatment (absence of parametrial interstitial implants and use of cervical EBRT boost) and patients' characteristics (age, comorbidities) may explain such results.

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.

Optimal treatment in locally advanced cervical cancer

Introduction: Locally advanced cervical cancer (LACC) (International Federation of Gynecology and Obstetrics (FIGO) 2009/2018 - stages IB2-IVA/IB3-IVA, respectively) is treated using a multimodal approach that includes chemoradiotherapy followed by brachytherapy.Areas covered: This review provides an overview of the progress made over the past decade in the treatment of LACC. Prognostic factors, FIGO classification and the role of imaging staging will be discussed. Efficacy of external-beam radiotherapy, brachytherapy and chemotherapy will be detailed. Indications for para-aortic staging lymphadenectomy and adjuvant hysterectomy, as well as follow-up and special population, will be covered.Expert opinion: The initial workup is one of the most crucial steps in the optimal care of patients, which should be realized by a multidisciplinary expert team. With the implementation of modern conformal radiotherapy techniques, the local control rate has been optimized. Nevertheless, 40% of patients experience recurrence with distant metastasis and a dismal prognosis. Currently, a clear benefit of neo- and adjuvant chemotherapy has not been established. The future likely involves (1) improved selection of patients for whom treatment intensification is justified, (2) a combination of new drugs with chemoradiation that are currently being tested in trials, and (3) the development of tailored treatment based on molecular characteristics.

Brachytherapy or external beam radiotherapy as a boost in locally advanced cervical cancer: a Gynaecology Study Group in the Italian Association of Radiation and Clinical Oncology (AIRO) review

This review analyzes the experience and trends in external beam radiotherapy for delivering a boost in locally advanced cervical cancer, identifying whether radiation therapy modalities impact clinical outcomes with the ultimate aim of evaluating alternatives to brachytherapy. Three independent Italian radiation oncologists conducted a literature search on different external beam radiotherapy boost modalities in locally advanced cervical cancer. The search yielded 30 studies. Eight dosimetric studies, evaluating target coverage and dose to organs at risk, and nine clinical investigations, reporting clinical outcomes, were analyzed. Dosimetric studies comparing external beam radiotherapy boost with brachytherapy produced divergent results, while clinical studies were limited by their retrospective nature, heterogeneous doses, radiation schedules, volumes and techniques, diverse follow-up times, and small cohorts of patients. Evidence emerged that high-tech external beam radiotherapy seemed no better than image-guided brachytherapy for delivering a boost in locally advanced cervical cancer. Prospective clinical studies comparing high-tech external beam radiotherapy and image-guided brachytherapy should be encouraged.

Venezia applicator with oblique needles improves clinical target volume coverage in distal parametrial tumor residue compared to parallel needles only

Purpose

Residual distal parametrial involvement after radiochemotherapy is a true challenge for brachytherapists since the width and asymmetry of high-risk clinical target volume (HR-CTV) are difficult to cover properly with a standard implant.

Material and methods

Dosimetric plans of five patients treated with Venezia advanced gynecological applicator at our institution were reviewed. For each patient, we compared the original plan with a new plan where oblique needles were removed and re-optimized manually. Optimization process was halted when EQD2₁₀ D₉₀ HR-CTV reached 90 Gy, when one hard constraint to organs at risk (OARs) was reached according to the EMBRACE II protocol, or when dose-rate of one of OARs exceeded 0.6 Gy/h.

Results

Tumors were large; median HR-CTV volume was 64 cc and median distance between tandem and outer contour of HR-CTV was 40 mm. For the five patients, HR-CTV EQD2₁₀ D₉₀ was superior in the plan using oblique needles, with a median difference of 6.5 Gy (range, 1.7-8.5 Gy). Median D₉₀ HR-CTV and intermediate-risk CTV (IR-CTV) were significantly increased with oblique needles: 85.9 Gy (range, 83.2-90.3 Gy) vs. 81.5 Gy (range, 77.4-84 Gy), and 68.7 Gy (range, 66.3-72.3 Gy) vs. 67 Gy (range, 64.3-69.1 Gy), p = 0.006 for both. There were no significant differences in the dose to OARs. Plans with only parallel needles had less favorable dose distribution, with cold spots on the outer parametria and higher vaginal activation to compensate parametrial coverage in its inferior part.

Conclusions

Venezia^TM applicator permits reproducible application to increase CTV coverage in patients with distal parametrial tumor residue during brachytherapy, while maintaining acceptable dose to OARs.

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

PURPOSE

This 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 MATERIALS

From 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.

RESULTS

The 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).

CONCLUSIONS

No difference in treatment results was observed between CT-based and TAUS-based approaches. However, TAUS-BT had higher vaginal toxicity in our retrospective analysis.

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.

Advanced cervical cancer in young women: imaging study of late and very late radiation-related side effects after successful treatment by combined radiotherapy

Background

Radical combined radiotherapy (RT) is a standard treatment for advanced cervical cancer. The aim of our study was to identify morphological late (≥6 months) and very late (≥5 years) radiation-related comorbidities on computed tomography (CT), positron emission tomography/computerized tomography (PET/CT) or magnetic resonance imaging (MRI) scans in young females who survived ≥5 years since RT and were considered as successfully treated. Secondly, we studied a rate of clinically silent radiation-related toxicities apparent on imaging scans that might influenced on future well-being of survived females. Thirdly, we analyzed reasons why patients underwent imaging scans.

Methods

We included 41 subjects aged under 50 years (mean 41.8±7.2 years, median 41 years), who survived ≥5 years since RT, with at least one available imaging scan ≥3 years since RT. The mean time between RT and the last available scan was 12.3±7.9 years (median 9 years); the mean time of clinical follow-up was 15.4±7.1 years (median 14 years).

Results

Fourteen (34.1%) females underwent the first imaging scan in emergency situation and 27 (65.9%) patients due to variable chronic complaints. Grade III-V radiation-related comorbidities occurred in 19 (46.3%) females including one case of death due to radiation-induced osteosarcoma. In 14 of 19 patients, comorbidities were multiple. Four (9.8%) females suffered from life-threatening complications (grade IV): one from an uretero-arterial fistula with massive hematuria and 3 from bowel perforations. Eleven (26.8%) subjects suffered from bowel strictures with ileus development, they underwent mean 1.7±0.8 surgery (median 1.5). The mean time since RT to the first surgery for intestinal complications was 5.4±6.0 years (median 3 years), to the second 12.0±9.6 years (median 11.5 years) and to the third surgery 9.0±4.2 years (median 9 years). Late fistulas formations (vesico-recto-vaginal) were seen in 6 (14.6%) patients. Bone complications were diagnosed in 9 (22.0%) of treated females, one case of osteosarcoma included, 4 of 9 bone complications were clinically silent. In 5 (12.2%) subjects, toxicities grade III-IV first time manifested >5 years since RT, majority of them were multiple. The bowel perforation and fistulas formations were the earliest manifested grade III-IV toxicities, with median time 3 years since RT, the bone complications were the latest manifested with median time 16 years since RT.

Conclusions

Our study is not able to bring information about the incidence of late and very late radiation related comorbidities, according to International Federation of Gynecology and Obstetrics (FIGO) recommendations patients are clinically followed only for 5 years and imaging cross-sectional scans are not recommended. However, our study shows that if females successfully treated for advanced cervical cancer report abdominal/pelvic clinical problems, it is highly probable their imaging scans will reveal late radiation related side-effects that may affect the rest of their life. It puts forward question whether females after radical RT should been regularly followed by cross-sectional imaging methods.

Aiming for 100% Local Control in Locally Advanced Cervical Cancer: The Role of Complex Brachytherapy Applicators and Intraprocedural Imaging

The use of brachytherapy for the treatment of gynecologic malignancies, particularly cervical cancer, has a long and rich history that is nearly as long as the history of radiation oncology itself. From the first gynecologic brachytherapy treatments in the early 20th century to the modern era, significant transformation has occurred driven largely by advancements in technology. The development of high-dose rate sources, remote afterloaders, novel applicators, and 3-dimensional image guidance has led to improved local control, and thus improved survival, solidifying the role of brachytherapy as an integral component in the treatment of locally advanced cervical cancer. Current research efforts examining novel magnetic resonance imaging sequences, active magnetic resonance tracking, and the application of hydrogel aim to further improve local control and reduce treatment toxicity.

Automatic segmentation and applicator reconstruction for CT-based brachytherapy of cervical cancer using 3D convolutional neural networks

In this study, we present deep learning-based approaches to automatic segmentation and applicator reconstruction with high accuracy and efficiency in the planning computed tomography (CT) for cervical cancer brachytherapy (BT). A novel three-dimensional (3D) convolutional neural network (CNN) architecture was proposed and referred to as DSD-UNET. The dataset of 91 patients received CT-based BT of cervical cancer was used to train and test DSD-UNET model for auto-segmentation of high-risk clinical target volume (HR-CTV) and organs at risk (OARs). Automatic applicator reconstruction was achieved with DSD-UNET-based segmentation of applicator components followed by 3D skeletonization and polynomial curve fitting. Digitization of the channel paths for tandem and ovoid applicator in the planning CT was evaluated utilizing the data from 32 patients. Dice similarity coefficient (DSC), Jaccard Index (JI), and Hausdorff distance (HD) were used to quantitatively evaluate the accuracy. The segmentation performance of DSD-UNET was compared with that of 3D U-Net. Results showed that DSD-UNET method outperformed 3D U-Net on segmentations of all the structures. The mean DSC values of DSD-UNET method were 86.9%, 82.9%, and 82.1% for bladder, HR-CTV, and rectum, respectively. For the performance of automatic applicator reconstruction, outstanding segmentation accuracy was first achieved for the intrauterine and ovoid tubes (average DSC value of 92.1%, average HD value of 2.3 mm). Finally, HDs between the channel paths determined automatically and manually were 0.88 ± 0.12 mm, 0.95 ± 0.16 mm, and 0.96 ± 0.15 mm for the intrauterine, left ovoid, and right ovoid tubes, respectively. The proposed DSD-UNET method outperformed the 3D U-Net and could segment HR-CTV, bladder, and rectum with relatively good accuracy. Accurate digitization of the channel paths could be achieved with the DSD-UNET-based method. The proposed approaches could be useful to improve the efficiency and consistency of treatment planning for cervical cancer BT.

[Can stereotactic body radiotherapy replace brachytherapy for locally advanced cervical cancer? French society for radiation oncology statement]

Brachytherapy is part of the treatment of locally advanced cervical cancers, accounting for about half of the total delivered dose. The benefit of dose escalation is the most important in advanced cases or if the tumor has responded poorly. The use of interstitial implantations makes it possible to reach doses of the order of 85 to 90Gy (including external beam radiotherapy contribution) in most patients, through image-guided approaches. Brachytherapy delivery is one of the quality criteria for patient care. To date, no data allow us to consider as an alternative the use of external boost through intensity-modulated or stereotactic body radiotherapy. Indeed, the doses delivered to the tumor and the capacity to spare normal tissues remains lower, as compared to what is permitted by brachytherapy. It is therefore appropriate for centers that do not have access to the technique to establish networks with centers where brachytherapy is performed, to allow each patient to have access to the technique. It is also necessary to promote brachytherapy teaching. The issue of reimbursement will be crucial in the coming years to maintain expertise that is today insufficiently valued in its financial aspects, but has a very high added value for patients.

A new score based on biomarker values to predict the prognosis of locally advanced cervical cancer

OBJECTIVE

To define a prognostic score based on pretreatment values of leucocyte, platelet and hemoglobin in locally advanced cervical cancer (LACC).

MATERIAL AND METHODS

We conducted a prospective study of 238 patients for LACC with negative PET imaging in the para-aortic (PA) area and who were undergoing laparoscopic PA lymphadenectomies. All patients were treated with chemo-radiation and brachytherapy.

RESULTS

Patients had clinical International Federation of Gynecology and Obstetrics stages IB2 (n = 76), IIA (n = 13), IIB (n = 122), III (n = 18) or IVA (n = 9). We identified three biological parameters (at the time of diagnosis) with three cut-offs which impacted disease free survival (DFS) and overall survival (OS): <12 g/dL for hemoglobin, >10,000/μL for leucocyte and >300 × 109/L for platelet. A score is calculated, as shown in the table below, by adding the scores of all three biological parameters together (with a maximum score of three). DFS at 36 months was 87.3% [78.3-97.4], 58% [45-74.6], 79.1% [71.1-88], 58% [45-74.6] and 56.8% [37.8-85.4] for scores of 0, 1, 2 and 3 respectively. OS at 36 months was 92.6% [84.9-100], 84% [76.6-92.1], 62.5% [48.9-79.9] and 67% [46.8-96] for scores of 0, 1, 2 and 3 respectively.

CONCLUSION

This score includes three biomarkers with easily remembered cut-offs that allow us to identify, at the time of diagnosis, those patients with a high risk of relapse (scores of two or three) and those requiring dose escalation.

Evaluation of an MR-only interstitial gynecologic brachytherapy workflow using MR-line marker for catheter reconstruction

PURPOSE

Magnetic resonance imaging (MRI) offers excellent soft-tissue contrast enabling the contouring of targets and organs at risk (OARs) during gynecological interstitial brachytherapy procedure. Despite its benefit, one of the main challenges toward MRI-only workflows is that the implanted catheters are not reliably visualized on MR images. This study aims to evaluate the feasibility of MR-only workflow using an in-house MR line marker during interstitial gynecological high-dose-rate (HDR) brachytherapy.

METHODS AND MATERIALS

Ten patients diagnosed with locally advanced cervical cancer treated with HDR brachytherapy were included in this study. The hybrid CT/MR-treated plan was used as the study reference plan. Five users manually reconstructed the catheter's path on MR images (3D T1- and T2-weighted). Subsequently, the dwell positions from the users' plans were superimposed on the reference plans to evaluate the dosimetric impact of the using MR-only for catheter reconstruction in comparison with hybrid CT/MR approach. Variability of dwell positions between users and reconstruction time was also evaluated.

RESULTS

More than 96.90% of catheter reconstruction variations were < 2 mm. No statistical differences were reported between MR-only and hybrid CT/MR in gross tumor volume D₉₈ and high-risk clinical target volume D₉₀, respectively. For the OARs (bladder, sigmoid, rectum, and bowel), no significant changes were observed in any dose metrics between MR-only and hybrid CT/MR. The average reconstruction time was 51 ± 10 minutes across all ten patients.

CONCLUSION

The feasibility of MR-only workflow using MR line marker during interstitial gynecological HDR brachytherapy has been validated in this study. The results show that the MR-only workflow is equivalent to the conventional hybrid CT/MR approach in terms of gross tumor volume and high-risk clinical target volume coverage and respecting of OARs dose limits.

MiR-1193 Inhibits the Malignancy of Cervical Cancer Cells by Targeting Claudin 7 (CLDN7)

Objective

MicroRNAs (miRNAs) are highly involved in cancer development, including in cervical cancer (CC). In this study, we aimed to investigate the role and possible mechanism of a poorly studied miRNA, miR-1193, in CC progression.

Materials and Methods

Expression of miR-1193 was determined in 60 pairs of cervical samples. The impacts of miR-1193 on CC cell proliferation, invasion and migration capacities were verified by CCK-8, transwell and wound healing assays, respectively. Then, bioinformatics prediction, luciferase reporter assay, qRT-PCR and Western blot were successively conducted to study the targeting of claudin 7 (CLDN7) by miR-1193. After CLDN7 was restored in miR-1193-overexpressed cells, the rescue effects were determined. Finally, CLDN7 expression was analyzed in cervical samples, and its expression correlation with miR-1193 was explored.

Results

Compared with paired normal tissues, miR-1193 was sharply decreased in abnormal tissues (intraepithelial lesions and cancerous tissues). Especially, miR-1193 expression was gradually decreased in low-grade squamous intraepithelial lesions, high-grade squamous intraepithelial lesions and CC. Enforced expression of miR-1193 inhibited CC cell proliferation, invasion and migration. Mechanistically, we confirmed CLDN7 as a target of miR-1193, and restoration of CLDN7 robustly rescued the tumor suppressing effects of miR-1193 in CC cells. CLDN7 was upregulated in abnormal cervical tissues and its expression exhibited inverse correlation with that of miR-1193 in CC.

Conclusion

Our results suggested that miR-1193 exerted tumor inhibitory roles in CC malignancy by directly targeting CLDN7.

Comprehensive analysis of patient outcome after local recurrence of locally advanced cervical cancer treated with concomitant chemoradiation and image-guided adaptive brachytherapy

INTRODUCTION

Since dose escalation allowed by image-guided adaptive brachytherapy (IGABT) in locally advanced cervical cancer (LACC), local relapses have become a rare event. Only scarce data are available on the outcome of patients experiencing a local relapse after IGABT.

METHODS

Between 2004 and 2016, all consecutive patients treated at Gustave Roussy Institute for LACC and receiving concomitant chemoradiation and IGABT were analysed. Clinical and treatment-related prognostic factors for survival after local relapse were searched, in order to potentially identify patients requiring salvage treatment.

RESULTS

Two hundred and fifty-nine patients were treated during this period. With a median follow-up of 4.1 years, 10.8% (n = 28) had a local relapse. Among these patients, 53.6% had synchronous lymph nodes or distant metastatic relapse and only 13 patients (5% of all patients) had isolated local relapse. After local relapse, median survival was 47 months and three patients were alive at last follow-up. Only three patients with local relapse could receive salvage surgery (10.7%). Metastases occurrence and pelvic wall involvement were the main contraindications (67.9%) for salvage surgery. Among the three patients treated with surgery, two are still alive at last follow-up without significant complication. Improved survival was observed among the two patients who could have surgery (p = .02). Local progression led to serious symptoms in 75% of patients. Only the time interval between brachytherapy and relapse (<1 year) was prognostic for 2-year overall survival (p = .005).

CONCLUSION

Salvage surgery is feasible in a very low number of highly selected patients with local relapse following IGABT. Local failure is a major cause of severe local symptoms, confirming that every effort should be done to achieve long-term local control through dose escalation.

Lessons from radiochemotherapy and modern image-guided adaptive brachytherapy followed by hysterectomy

PURPOSE

To analyze the clinical outcomes and the safety of radiochemotherapy (RCT) and image-guided adaptive brachytherapy (IGABT) and to evaluate the impact of hysterectomy (HT) as completion of treatment for cervical cancer.

METHODS AND MATERIALS

145 patients with locally advanced cervical cancer were treated at our institution. Patients underwent RCT and IGABT, then hysterectomy (HT) as completion of treatment was performed, with the exception of patients with surgical contraindications, para aortic metastatic disease or patients who refused surgery. Clinical outcomes and morbidity were retrospectively reviewed in both groups. Local relapse free survival (LRFS), pelvic relapse free survival (PRFS) and overall survival (OS) were analyzed.

RESULTS

Completion HT was performed in 90 (62.1%) patients. Complete histological response and microscopic disease were found in 77 patients (85.6%). Local relapse was observed in 14 patients (9.6%) without differences between completion HT group and the definitive RCT and IGABT group (Odds Ratio OR = 1.73 [0.57-5.23], p = 0.33). The estimated 3-year LRFS and PRFS for the entire population were respectively 90% [84%-94%] and 93% [87%-96%], with no significant differences between them (respectively Hazard Ratio HR = 0.57 [0.20-1.64], p = 0.30 and HR = 0.37 [0.10-1.31], p = 0.12). The estimated 3-year OS rate for the whole population was 84% [75%-91%] with no significant differences between groups (HR = 0.81 [0.32-2.06], p = 0.65). Regarding morbidity, grade ≥ 2 vaginal toxicity was more frequent in the definitive RCT and IGABT group (43.6% vs 26.7%, p = 0.04). All grade 4 toxicity events were reported in the completion HT group.

CONCLUSIONS

Due to high severe toxicity, RCT and IGABT with dose escalation followed by completion hysterectomy don't seem compatible. No benefit and increased severe late morbidity were observed. Combined intracavitary/interstitial technique is mandatory in large target volume at brachytherapy.

High precision radiotherapy including intensity-modulated radiation therapy and pulsed-dose-rate brachytherapy for cervical cancer: a retrospective monoinstitutional study

Purpose

To analyse the survival outcomes and toxicity profile of patients treated with pulsed-dose-rate (PDR) brachytherapy (BT) after intensity-modulated radiation therapy (IMRT) for uterine cervical cancer in a single institution.

Material and methods

Between March 2011 and December 2014, 50 patients with histologically proven stages IB1-IVB cervical cancer were treated with IMRT followed by PDR-BT boost. Radiation treatment consisted of IMRT to pelvic with or without paraaortic lymph nodes to a total dose of 45-50.4 Gy. Weekly concomitant chemotherapy was administered to 45 patients. PDR-BT boost was delivered with a median dose of 30 Gy to the high-risk clinical target volume (HR-CTV) after a median time of 14 days since IMRT. Acute and late toxicity were evaluated by Radiation Therapy Oncology Group (RTOG) - European Organization for Research and Treatment of Cancer (EORTC) scoring criteria and Subjective Objective Management Analytic-Late Effects of Normal Tissues (SOMA-LENT) criteria.

Results

Two patients had tumour persistence at 6 months after the end of BT. After a median follow-up of 33 months, 6 distant metastases with or without regional relapse were observed. The 1- and 5-year progression-free survival was 83% (95% CI: 69-91%) and 76% (95% CI: 61-86%), whereas the 3- and 5-year overall survival was 91% (95% CI: 78-97%) and 76% (95% CI: 56-88%), respectively. Urinary and rectal toxicity higher than grade 2 was observed in 6.3% and 17% of patients, respectively. Five patients (10.6%) had grade 4 gastrointestinal toxicity requiring colostomy.

Conclusions

Our study confirms that the combination of IMRT and PDR-BT can be considered an effective treatment for cervical cancer, ensuring high local control, despite the high percentage of locally advanced disease.

Development and assessment of 3D-printed individual applicators in gynecological MRI-guided brachytherapy

Purpose

To evaluate the clinical use of 3D printing technology for the modelling of individual applicators for advanced gynecological tumors in magnetic resonance imaging (MRI)-based brachytherapy (BT).

Material and methods

We tested individually designed 3D-printed applicators in nine patients with advanced gynecological cancer. Before BT was performed, all patients were treated with external beam radiotherapy (EBRT). The most common indication for individualized BT was advanced gynecological tumors where the use of standard BT applicators was not feasible. Other indications were suboptimal dose-volume histogram (DVH) parameters for high-risk clinical target volume (CTV-T_HR) at the first BT (V₁₀₀ ≤ 90% of CTV-T_HR volume and D₉₈ ≤ 80%, D₉₀ ≤ 100%, and D₁₀₀ ≤ 60% of dose aim). The EQD₂ dose aim to the target volume D₉₀ CTV-T_HR per one BT fraction was 20 Gy for cervical or recurrent endometrial cancer and 16 Gy for vaginal cancer patient. The first BT with the standard applicator in situ was used as the virtual plan for designing a 3D-printed applicator. The next BT was performed with a 3D-printed applicator in situ. The primary endpoint was to improve CTV-T_HR DVH parameters without exceeding the dose to the organs at risk (OARs).

Results

All DVH parameters for CTV-T_HR were significantly higher with the use of an individually designed applicator. Mean D₉₀ CTV-T_HR improved from 14.1 ±5.4 Gy to 22.0 ±2.5 Gy and from 7.1 Gy to 16.2 Gy for cervical/recurrent endometrial and vaginal cancer, respectively (p < 0.001). The mean D_2cm³ bladder, rectum, sigmoid, and bowel dose was within institutional dose constraints, and increased from 13.0 ±1.5 Gy to 13.6 ±1.5 Gy (p = 0.045), 10.8 ±1.2 Gy to 11.7 ±1.3 Gy (p = 0.004), 8.9 ±3.2 Gy to 10.3 ±3.3 Gy (p = 0.008), and 8.7 ±3.8 Gy to 9.2 ±3.1 Gy (p = 0.2).

Conclusions

With the use of individual 3D-printed applicators, all DVH parameters for CTV-T_HR significantly improved without compromising the dose constraints for the OARs.

Management for locally advanced cervical cancer: new trends and controversial issues

This article reviewed new trends and controversial issues, including the intensification of chemotherapy and recent brachytherapy (BT) advances, and also reviewed recent consensuses from different societies on the management of locally advanced cervical cancer (LACC). Intensive chemotherapy during and after radiation therapy (RT) was not recommended as a standard treatment due to severe toxicities reported by several studies. The use of positron emission tomography-computed tomography (PET-CT) and magnetic resonance imaging (MRI) for pelvic RT planning has increased the clinical utilization of intensity-modulated radiation therapy (IMRT) for the evaluation of pelvic lymph node metastasis and pelvic bone marrow. Recent RT techniques for LACC patients mainly aim to minimize toxicities by sparing the normal bladder and rectum tissues and shortening the overall treatment time by administering a simultaneous integrated boost for metastatic pelvic lymph node in pelvic IMRT followed by MRI-based image guided adaptive BT.