External beam techniques to boost cervical cancer when brachytherapy is not an option-theories and applications

Stereotactic body radiotherapy boost as an alternative to brachytherapy for cervical cancer: A scoping review

PURPOSE

This scoping review aims to evaluate the evidence for stereotactic body radiotherapy (SBRT) boost as a potential alternative for brachytherapy (BCT) in treating cervical cancer.

MATERIAL AND METHODS

A comprehensive literature search was conducted across multiple databases. Studies investigating SBRT boost in cervical cancer patients who were either contraindicated for or refused BCT were included. The review examined SBRT efficacy and safety.

RESULTS

Sixteen studies were included, encompassing prospective (n = 4) and retrospective cohort studies (n = 8), as well as phase I and II trials (n = 4). The most common SBRT boost dose was 25 Gray(Gy)/5 fractions (ranging from 18 to 40 Gy/3-5 fractions). Local control rates at 1-year, 3-year, and 5-year ranged from 86 % to 100 %, 78-92 %, and 81-92 %, respectively. Overall survival (OS) rates at 1-year, 3-year, and 5-year rates ranged from 49 % to 95 %, 50-77 %, and 50-69 %, respectively. Two studies reported a pathological complete response rate of 93 % and 94 % three months after the SBRT boost. Most studies reported low rates of late grade 3 or higher genitourinary (0-14 %) and gastrointestinal (0-26 %) toxicities. The overall incidence of rectovaginal fistulas ranged from 0 % to 13 %.

CONCLUSION

This scoping review suggests SBRT boost as a promising alternative to selected cervical cancer patients who cannot receive BCT. The results indicate a high local control with acceptable toxicity profiles. However, further research is needed to define optimal SBRT boost parameters, identify patient selection criteria, and address knowledge gaps regarding long-term outcomes and cost-effectiveness.

Locally Advanced Gastric Cancer Management: A Cost-Effectiveness Analysis

Across the nation, patients with locally advanced gastric cancer (LAGC) are managed with modalities including upfront surgery (US) and perioperative chemotherapy (PCT). Preoperative therapies have demonstrated survival benefits over US and thus long-term outcomes are expected to vary between the options. However, as these 2 modalities continue to be regularly employed, we sought to perform a decision analysis comparing the costs and quality-of-life associated with the treatment of patients with LAGC to identify the most cost-effective option. We designed a decision tree model to investigate the survival and costs associated with the most commonly utilized management modalities for LAGC in the United States: US and PCT. The tree described costs and treatment strategies over a 6-month time horizon. Costs were derived from 2022 Medicare reimbursement rates using the third-party payer perspective for physicians and hospitals. Effectiveness was represented using quality-adjusted life-years (QALYs). One-way, two-way, and probabilistic sensitivity analyses were utilized to test the robustness of our findings. PCT was the most cost-effective treatment modality for patients with LAGC over US with a cost of $40,792.16 yielding 3.11 QALYs. US has a cost of $55,575.57 while yielding 3.15 QALYs; the incremental cost-effectiveness ratio (ICER) was $369,585.25. One-way and two-way sensitivity analyses favored PCT in all variations of variables across their standard deviations. Across 100,000 Monte Carlo simulations, 100% of trials favored PCT. In our model simulating patients with LAGC, the most cost-effective treatment strategy was PCT. While US demonstrated improved QALYs over PCT, the associated cost was too great to justify its use.

Locally advanced squamous cervical carcinoma (M0): management and emerging therapeutic options in the precision radiotherapy era

Squamous cervical carcinoma (SCC) requires particular attention in diagnostic and clinical management. New diagnostic tools, such as (positron emission tomography-magnetic resonance imaging) PET-MRI, consent to ameliorate clinical staging accuracy. The availability of new technologies in radiation therapy permits to deliver higher dose lowering toxicities. In this clinical scenario, new surgical concepts could aid in general management. Lastly, new targeted therapies and immunotherapy will have more room in this setting. The aim of this narrative review is to focus both on clinical management and new therapies in the precision radiotherapy era.

Hypofractionated versus standard chemoradiotherapy in the definitive treatment of uterine cervix cancer: interim results of a randomized controlled clinical trial

PURPOSE

Concurrent chemoradiation has been the mainstay of treatment for cervix cancer. We aimed to evaluate the non-inferiority of hypofractionated chemoradiation.

METHODS

This study was designed as a phase 2, 1:1 randomized, investigator-blinded, controlled, non-inferiority trial and we report the interim results after 50% accrual. Cervical cancer patients with FIGO stages IIA-IIIC were recruited from April 2021 to September 2022. The intervention consisted of 40 Gy of 3D-conformal radiation therapy (RT) in 15 fractions over 3 weeks. In the control group, patients received standard chemoradiation of 45 Gy in 25 fractions over 5 weeks. Both groups received concurrent weekly cisplatin (40 mg/m2). Intravaginal brachytherapy of 28 Gy in 4 weekly fractions was delivered starting 1 week after the end of chemoradiation. The primary outcome was complete clinical response(CCR) at 3 months. Secondary outcomes included acute gastrointestinal (GI), genitourinary(GU), skin, and hematologic toxicities. A p value less than 0.05 was considered significant for analyses.

RESULTS

59 patients were randomized; 30 in the control group and 29 in the intervention group. 20/30 (66.7%) of the patients in the control group and 19/29 (65.5%) in the intervention group achieved a CCR (absolute difference of 0.011, 95% CI - 0.23 to 0.25, p value: 0.13). There was a significantly higher rate of acute grade ≥ 3 GI toxicity in the intervention group (27.6%) compared with the control group (6.7%) (p value 0.032).

CONCLUSIONS

Despite an absolute difference of 1.1% in the 3-month CCR, our interim analysis failed to show the non-inferiority of the hypofractionated chemoradiation. Due to the higher GI toxicities, we will continue this trial using intensity-modulated radiation therapy.

REGISTRATION NUMBER AND DATE

ClinicalTrials.gov: NCT04831437, 2021.4.1.

Dosimetric comparison of stereotactic MR-guided radiation therapy (SMART) and HDR brachytherapy boost in cervical cancer

PURPOSE

The standard of care in locally advanced cervical cancer (LACC) is concomitant chemoradiotherapy followed by high-dose-rate brachytherapy (HDR-BT). Although previous studies compared HDR-BT with stereotactic body radiotherapy (SBRT), there is scarce data regarding the dosimetric outcomes of stereotactic MR-guided adaptive radiation therapy (SMART) boost in lieu of HDR-BT.

METHODS AND MATERIALS

In this single-institutional in-silico comparative study, LACC patients who were definitively treated with external beam radiotherapy followed by HDR-BT were selected. Target volumes and organs at risk (OARs) were delineated in MRI and HDR-planning CT. An HDR-BT and a SMART boost plan were generated with a prescribed dose of 28 Gy in four fractions for all patients. The HDR-BT and SMART boost plans were compared in regard to target coverage as well OARs doses.

RESULTS

Mean EQD2 D90 to HR-CTV and IR-CTV for HDR-BT plans were 89.7 and 70.5 Gy, respectively. For SMART, the mean EQD2 D90 to HR-PTV, HR-CTV, and IR-CTV were 82.9, 95.4, and 70.2 Gy, respectively. The mean D2cc EQD2 of bladder, rectum, and sigmoid colon for HDR-BT plans were 86.4, 70.7, and 65.7 Gy, respectively. The mean D2cc EQD2 of bladder, rectum, and sigmoid colon for SMART plans were 81.4, 70.8, and 73.6 Gy, respectively. All dose constraints in terms of target coverage and OARs constraints were met for both HDR-BT and SMART plans.

CONCLUSIONS

This dosimetric study demonstrates that SMART can be applied in cases where HDR-BT is not available or ineligible with acceptable target coverage and OAR sparing. However, prospective clinical studies are needed to validate these results.

Development and validation of a scatter-corrected CBCT image-guided method for cervical cancer brachytherapy

Background and purpose

Multiple patient transfers have a nonnegligible impact on the accuracy of dose delivery for cervical cancer brachytherapy. We consider using on-site cone-beam CT (CBCT) to resolve this problem. However, CBCT clinical applications are limited due to inadequate image quality. This paper implements a scatter correction method using planning CT (pCT) prior to obtaining high-quality CBCT images and evaluates the dose calculation accuracy of CBCT-guided brachytherapy for cervical cancer.

Materials and methods

The CBCT of a self-developed female pelvis phantom and five patients was first corrected using empirical uniform scatter correction in the projection domain and further corrected in the image domain. In both phantom and patient studies, the CBCT image quality before and after scatter correction was evaluated with registered pCT (rCT). Model-based dose calculation was performed using the commercial package Acuros®BV. The dose distributions of rCT-based plans and corrected CBCT-based plans in the phantom and patients were compared using 3D local gamma analysis. A statistical analysis of the differences in dosimetric parameters of five patients was also performed.

Results

In both phantom and patient studies, the HU error of selected ROIs was reduced to less than 15 HU. Using the dose distribution of the rCT-based plan as the baseline, the γ pass rate (2%, 2 mm) of the corrected CBCT-based plan in phantom and patients all exceeded 98% and 93%, respectively, with the threshold dose set to 3, 6, 9, and 12 Gy. The average percentage deviation (APD) of D90 of HRCTV and D2cc of OARs was less than 1% between rCT-based and corrected CBCT-based plans.

Conclusion

Scatter correction using a pCT prior can effectively improve the CBCT image quality and CBCT-based cervical brachytherapy dose calculation accuracy, indicating promising prospects in both simplified brachytherapy processes and accurate brachytherapy dose delivery.

Stereotactic Body Radiotherapy Boost with the CyberKnife for Locally Advanced Cervical Cancer: Dosimetric Analysis and Potential Clinical Benefits

(1) Aim: To compare the treatment plans of stereotactic body radiotherapy (SBRT) with CyberKnife (CK) and high-dose-rate (HDR) intracavitary/interstitial brachytherapy (IC/ISBT) and examine the feasibility of CK-SBRT as a viable alternative to BT in patients with locally advanced cervical cancer (LACC). (2) Methods: A BT plan of 28 Gy in four fractions delivered previously to 20 patients with LACC was compared with a CK plan based on the same CT images with structures delineation for BT. The SBRT treatment plan was further divided according to two different approaches, with the high-risk planning target volume (HR-PTV) defined by the high-risk clinical target volume (HR-CTV) without and with a 5 mm margin, which were named CK-CTV plan and CK-PTV plan, respectively. The dose distributions and dosimetric parameters of the target volumes and organs at risk (OARs) were recorded and compared for the three boost plans. Radiobiological metrics were calculated based on the EUD for the hybrid plans. Additionally, the relationship between tumor volume and tolerance doses for the OARs in the BT plan and CK-PTV plan was investigated. (3) Results: Target coverage was better with the CK plan than with the BT plan, as the D95%, D98%, HI and CI of the CK-CTV plan and CK-PTV plan were higher than those of the BT plan; an exception was the D50%. Similarly, the TCP of the target was also significantly in favor of the CK hybrid plans (p < 0.01). For the OARs, the CK-CTV plan was superior to the BT plan as regards the rectum D2cc, bladder D2cc and bladder Dmax. The CK-PTV plan could achieve dosimetric parameters comparable to those of the BT plan for OARs concerning the small residual tumor volume. The NTCP of the rectum for the WPI+CK-CTV plans was significantly lower than that of the WPI+BT plans (p < 0.01). (4) Conclusions: CK-based SBRT can achieve better target coverage, dose sparing for the OARs and radiobiological effects compared with the BT plan for tumors that are not excessively large. CK-based SBRT could be an alternative option to administer a radiation boost for patients with LACC.

Online MR evaluation of inter- and intra-fraction uterus motions and bladder volume changes during cervical cancer external beam radiotherapy

Purpose/objective(s)

The purpose of the study was to assess the uterus motions and bladder volume changes of fractional movements in cervical sites throughout the external beam radiotherapy (EBRT) treatment.

Materials/methods

A prospective online MR imaging tracking study was conducted in EBRT 43 patients with at least 4 scans during each treatment (before: ultrasound scan, MRI scan, CBCT scan, after: MRI scan) were included. In order to improve the treatment repeatability, each patient was instructed to empty the bladder and drink 500 ml water 1 h before CT simulation and each treatment. If the ultrasound scan result reached the CT simulation volume of bladder, the treatment began. Bladder was outlined on the T2 weighted axial sequence and CBCT image by the two observers to avoid the influence of contouring. The data of bladder volume and scanning time were accurately recorded. The bladder volumes, filling rates and uterus motion were retrospectively analyzed by MIM software.

Results

Inter-fraction variation of the bladder volume was significant (p < 0.0001). Intra-fraction mean increase of the bladder volume was modest (30 cc) but significant (p < 0.001). Both inter- and intra-fraction of the uterus motion were significant. The average time between the pre-and post-fraction MRI scans was 27.82 ± 7.12 min (range 10–55 min) for IMRT plans and 24.14 ± 5.86 min (range7-38 min) for VMAT plan. Average bladder filling rate was 3.43 ml/min. The bladder filling rate did not change significantly with the course of treatment, but the bladder was more intolerant.

Conclusion

This is the most detailed assessment of intra-fraction and inter-fraction motion during EBRT for cervical cancer. Finally, this study will inform appropriate treatment margins for online adaptive radiotherapy. We suggest that at least one image scan is needed before the EBRT. The portable US scanner provides a quick but unreliable measurement of the bladder volume. There is a significant statistical difference between the results of ultrasonic scanning and that of image scanning.

Online Magnetic Resonance-Guided Radiotherapy (oMRgRT) for Gynecological Cancers

Radiation therapy (RT) is increasingly being used in gynecological cancer management. RT delivered with curative or palliative intent can be administered alone or combined with chemotherapy or surgery. Advanced treatment planning and delivery techniques such as intensity-modulated radiation therapy, including volumetric modulated arc therapy, and image-guided adaptive brachytherapy allow for highly conformal radiation dose delivery leading to improved tumor control rates and less treatment toxicity. Quality on-board imaging that provides accurate visualization of target and surrounding organs at risk is a critical feature of these advanced techniques. As soft tissue contrast resolution is superior with magnetic resonance imaging (MRI) compared to other imaging modalities, MRI has been used increasingly to delineate tumor from adjacent soft tissues and organs at risk from initial diagnosis to tumor response evaluation. Gynecological cancers often have poor contrast resolution compared to the surrounding tissues on computed tomography scan, and consequently the benefit of MRI is high. One example is in management of locally advanced cervix cancer where adaptive MRI guidance has been broadly implemented for adaptive brachytherapy. The role of MRI for external beam RT is also steadily increasing. MRI information is being used for treatment planning, predicting, and monitoring position shifts and accounting for tissue deformation and target regression during treatment. The recent clinical introduction of online MRI-guided radiation therapy (oMRgRT) could be the next step in high-precision RT. This technology provides a tool to take full advantage of MRI not only at the time of initial treatment planning but as well as for daily position verification and online plan adaptation. Cervical, endometrial, vaginal, and oligometastatic ovarian cancers are being treated on MRI linear accelerator systems throughout the world. This review summarizes the current state, early experience, ongoing trials, and future directions of oMRgRT in the management of gynecological cancers.

Stereotactic ablative body radiotherapy boost for cervical cancer when brachytherapy boost is not feasible

BACKGROUND

The purpose of this study was to analyze the treatment efficacy and safety of stereotactic ablative body radiotherapy (SABR) boost for cervical cancer patients not amenable to brachytherapy.

METHODS

A retrospective review of the medical records from single institution of 25 eligible patients was performed. The patients underwent pelvic radiotherapy (RT) in 25 or 28 fractions with a median dose of 45 Gy (range 44-50.4 Gy). SABR boost was delivered after pelvic RT, with a median dose of 25 Gy (range 20-33 Gy), and a median fraction number of 5 (range 4-6). 21 patients with a follow-up period of more than one year were included in the toxicity analysis, and hematuria and hematochezia that occurred later than 3 months after the RT were graded.

RESULTS

The median follow-up period after radiotherapy was 2.85 years (range 0.33-6.60). The 3-year local control, locoregional control, disease-free survival, and overall survival rates were 80.9%, 75.8%, 40.9%, and 77.1%, respectively. 5 patients experienced grade 3 toxicity (3 genitourinary, 3 gastrointestinal), and no grade 4-5 toxicity was reported. Univariate analysis showed that cumulative D_2cc in equivalent dose in 2 Gy fractions (EQD2) of rectum was marginally predictive for any grade of hematochezia (P = 0.051). Cumulative D_2cc EQD2 of bladder was not predictive for hematuria. In the receiver operating characteristic (ROC) curve analysis, the optimal threshold of cumulative rectal D_2cc EQD2 was 81.2 Gy for any grade of hematochezia.

CONCLUSION

SABR boost for cervical cancer was effective and tolerable. Although it cannot substitute brachytherapy, it can be a treatment option when brachytherapy is not possible.

Optimal use of radiotherapy in the definitive treatment of non-bulky IB-IIA cervical cancer: A population-based long-term survival analysis

Purpose

Although current clinical guidelines recommend surgery or radiotherapy for non-bulky IB-IIA cervical cancer, clinical data supporting the curative role of radiotherapy in the early-stage disease are insufficient. We evaluated the prognostic implications of definitive radiotherapy and determined its optimal use in clinical practice.

Methods

Patients with non-bulky (<4 cm) IB-IIA cervical cancer who underwent hysterectomy or primary radiotherapy between 1988 and 2015 were identified from the Surveillance, Epidemiology, and End Results database. Based on the use of brachytherapy and/or chemotherapy, the primary radiotherapy group was classified into three cohorts: hysterectomy vs. radiotherapy overall, with/without brachytherapy and/or chemotherapy (cohort A); radiotherapy and brachytherapy with/without chemotherapy (patients with external beam radiation alone were excluded, cohort B); radiotherapy with brachytherapy and chemotherapy (patients who did not receive chemotherapy were additionally excluded, cohort C). Disease-specific survival (DSS) after hysterectomy was compared to that after primary radiotherapy in each cohort.

Results

Among the 9,391 initially identified patients, 1,762, 1,244, and 750 patients were classified into cohorts A, B, and C, respectively, after propensity score matching. In cohort A, DSS after primary radiotherapy was inferior to that after hysterectomy (P = 0.001). In cohort B, a trend toward differential survival in favor of hysterectomy was observed with marginal significance (P = 0.061). However, in cohort C, DSS after primary radiotherapy was not significantly different to that after hysterectomy (P = 0.127). According to hazard rate function plots, patients receiving external beam radiation alone had an increased short-term risk of disease-specific mortality, whereas patients without evidence of chemotherapy had a distinct late risk surge at approximately 15 years of follow-up.

Conclusion

Optimizing radiotherapy methods with brachytherapy and the use of chemotherapy should be considered for the long-term curative efficacy of primary radiotherapy for non-bulky IB-IIA cervical cancer. Further studies are warranted to corroborate our results.

Stereotactic Body Radiation Therapy Boost in Patients With Cervical Cancer Ineligible for Brachytherapy

BACKGROUND

Standard treatment for locally advanced cervical cancer is external beam radiotherapy followed by brachytherapy (BT). Stereotactic body radiation therapy (SBRT) is a possible option for treating patients ineligible for BT.

PATIENTS AND METHODS

From October 2012 to July 2020, nine women with cervical cancer received SBRT to high-risk volumes. The Kaplan-Meier method was used to estimate the rates of overall and disease-free survival.

RESULTS

The median age was 52 years; 88% of patients had squamous carcinoma. Reasons for forgoing BT were cervical canal stenosis, treatment refusal and hematological disease. The median boost dose was 18 Gy and the median dose per fraction was 6 Gy. Median follow-up was 16 months. The median survival was 24 months, the actuarial 2-year OS rate was 70%, and median disease-free survival was 11 months. One grade 3 late vaginal toxicity was reported. No acute nor late grade 4 toxicities were observed.

CONCLUSION

SBRT boost in patients with cervical cancer ineligible for BT led to acceptable survival outcomes and a safe toxicity profile.

Contemporary external beam radiotherapy boost or high dose-rate brachytherapy boost for cervical cancer: a propensity-score-matched, nationwide, population-based cohort study

To estimate the survival effects of contemporary external beam radiotherapy (EBRT) boost modalities (intensity-modulated radiation therapy or volumetric modulated arc therapy) and high dose-rate brachytherapy (HDR-BT) boost in patients with cervical cancer (CC). Patients who had been diagnosed as having CC were recruited from the Taiwan Cancer Registry Database. Propensity score matching was performed, and Cox proportional-hazards model curves were used to analyze the all-cause mortality of patients who received standard whole-pelvis irradiation with different boost modalities. The matching process yielded a final cohort of 1,630 patients (815 in the EBRT boost and HDR-BT boost groups, respectively) eligible for further analysis. The multivariate Cox regression analyses indicated that the adjusted hazard ratio (95% confidence intervals) for EBRT boost compared with HDR-BT boost was 1.62 (1.43-1.84). Multivariable analysis revealed that the independent poor prognostic factors of all-cause mortality among patients with CC were adenocarcinoma, no chemotherapy, Charlson comorbidity index score ≥ 1, age ≥ 60 years, and advanced International Federation of Gynecology and Obstetrics stage. HDR-BT boost may be more beneficial than contemporary EBRT boost in selected patients with CC.

Feasibility Study of Robust Optimization to Reduce Dose Delivery Uncertainty by Potential Applicator Displacements for a Cervix Brachytherapy

Brachytherapy is an important technique to increase the overall survival of cervical cancer patients. However, a possible shift of the applicators in relation to the target and organs at risk may occur between imaging and treatment. Without daily adaptive brachytherapy planning, these applicator displacements can lead to a significant change in dose distribution. In order to resolve it, a robust optimization method had been developed using a genetic algorithm combined with a median absolute deviation as a robustness evaluation function. The resulting robustness plans from our strategy might be worth considering according to the GEC-ESTRO guidelines. From the point of view of dose delivery uncertainty from applicator displacement, the robust optimization may be considered with caution in a single-plan approach for High Dose Rate brachytherapy treatment planning and should be confirmed by a more thorough investigation.

Negative impact of the COVID-19 pandemic on the management of cervical cancer patients in Zambia

International travel has largely been suspended due to the COVID-19 pandemic. Due to this situation, Zambia has not been able to import radioactive isotopes for High Dose Rate (HDR) brachytherapy, Iridium 192 (I192) and this has led to suspension of treatment for patients. Cancer of the cervix is the most common cancer in Zambia and brachytherapy is a core component of the treatment armamentarium. Mitigation strategies may include external beam radiotherapy boost or hysterectomy but both systems are overburdened and fragile.

Dosimetric and radiobiological comparison of simultaneous integrated boost and sequential boost of locally advanced cervical cancer

Introduction Some patients with locally advanced cervical cancer (LACC) cannot undergo brachytherapy (BT). Possible treatment includes two-stage external beam radiotherapy (sequential boost - SEQ) or single-stage external beam radiotherapy (simultaneous integrated boost - SIB). The goal of this paper was to carry out dosimetric and radiobiological comparison of these techniques with respect to tumour and organs-at-risk (OARs) irradiation. Methods The anatomic data of six patients with LACC were used for this study. The single-stage SIB-VMAT (25, 27 or 30 fractions) and double-stage SEQ-VMAT (25 + 6 fractions) plans were developed to deliver EQD₂=50 Gy to the pelvic region and EQD₂=90 Gy to the tumour. The developed plans were compared with respect to an EQD₂ dose delivered to a tumour and to the OARs, expected tumour control probability and normal tissue complications probability. Results The developed SIB-VMAT and SEQ-VMAT plans had physical coverage of the CTV tumours with more than 95% of the prescribed dose delivered to more than 95% of the volume. The irradiation of the tumour for both SIB-VMAT and SEQ-VMAT has comparable EQD₂ values close to 87-88 Gy. SIB-VMAT treatment plans provided lower levels of irradiation of OARs than SEQ-VMAT plans. The optimal number of fractions for SIB-VMAT was 27. Conclusion SIB-VMAT is a better treatment option for patients with LACC that are not eligible for BT. Results show that both SIB-VMAT and SEQ-VMAT allowed good coverage of the tumour and high-quality dose delivery. SIB-VMAT allowed minimising irradiation of OARs and shortening the overall treatment time by a week.

Impact of adjuvant radiotherapy on the survival of women with optimally resected stage III endometrial cancer in the era of modern radiotherapy: a retrospective study

Background

The optimal adjuvant treatment for stage III endometrial cancer in the era of modern radiotherapy remains undefined. We investigated the benefit of adjuvant radiotherapy for women who underwent optimal resection for stage III endometrial cancer in the era of modern radiotherapy.

Methods

We retrospectively reviewed patients with endometrial cancer who were treated between 2010 and 2018. Adjuvant treatment included radiotherapy by modern radiotherapy techniques (intensity-modulated or volumetric modulated arc radiotherapy), chemotherapy, or both. Recurrence-free survival (RFS) and overall survival (OS) were calculated using the Kaplan-Meier method and analyzed via multivariate Cox proportional hazards models.

Results

One hundred sixty-one patients were initially included (52, 9, and 100 with stages IIIA, IIIB, and IIIC cancer, respectively); 154 patients (96%) received adjuvant therapy. Such adjuvant treatment was associated with improved RFS (p = 0.014) and OS (p = 0.044) over surgery alone. Adjuvant radiotherapy by modern radiotherapy techniques led to low incidence of acute (25%) and chronic (7%) grade ≥ 2 gastrointestinal toxicity. On univariate analysis, non-endometrioid histology and grade 3 status were associated with higher risks of tumor recurrence and death, whereas adjuvant radiotherapy alone or in combination chemotherapy reduced their risks. On multivariate analysis, non-endometrioid histology was associated with increased recurrence (hazard ratio [HR], 2.95; p = 0.009), whereas adjuvant radiotherapy alone or with chemotherapy was associated with lower recurrence (HR, 0.62; p = 0.042). Patients > 60 years of age (p = 0.038) as well as those with endometrioid histology (p = 0.045), lymphovascular space invasion (p = 0.031), and ≥ 2 positive lymph nodes (p = 0.044) benefited most from adjuvant radiotherapy.

Conclusions

Modern adjuvant radiotherapy (intensity-modulated or volumetric modulated arc radiotherapy) alone or with chemotherapy should be considered for women with optimally resected stage III endometrial cancer.

Trial registration

ClinicalTrials.gov, NCT04251676. Registered 24 January 2020. Retrospectively registered.

IMRT and brachytherapy comparison in gynaecological cancer treatment: thinking over dosimetry and radiobiology

Background

The role of radiotherapy and brachytherapy in the management of locally advanced cervical and endometrial cancer is well established. However, in some cases, intracavitary brachytherapy (ICBRT) is not recommended or cannot be carried out. We aimed to investigate whether external-beam irradiation delivered by means of intensity-modulated radiation therapy (IMRT) might replace ICBRT in gynaecological cancer when the standard ICBRT boost delivering cannot be administered for technical or clinical reasons.

Materials and methods

Fifteen already delivered treatments for gynaecological cancer patients were analysed. The treatments were performed through 3-dimensional conformal radiotherapy (3D-CRT) to the whole-pelvis up to the dose of 45–50.4 Gy followed by a boost dose administered with ICBRT in high-dose-rate or pulsed-dose-rate modality. For each patient, IMRT plans were elaborated to mimic the ICBRT. We analysed the ICBRT boost versus IMRT boost in terms of dosimetric and radiobiological aspects.

Results

Mean conformity index value calculated on boost volume was 0.73 for ICBRT and 0.97 for IMRT. Mean conformation number was 0.24 for ICBRT boost and 0.78 for IMRT boost. Mean normal tissue complication probability (NTCP) values for 3D-CRT plus ICBRT and for IMRT (pelvis plus boost) were, respectively, 28% and 5% for rectum; 1.5% and 0.1% for urinary bladder and 8.9% and 6.1% for bowel.

Conclusions

Our findings suggest that IMRT may represent a viable alternative in delivering the boost in patients diagnosed with gynaecological cancer not amenable to ICBRT.

Clinical outcomes following conventional external beam radiotherapy boost in Japanese patients with cervical cancer who are ineligible for intracavitary brachytherapy

OBJECTIVE

While external beam radiotherapy boost has been one of the standard management options for locally advanced cervical cancer that is not treatable with intracavitary brachytherapy, its efficacy remains unclear. We assessed clinical outcomes in Japanese patients with cervical cancer who underwent external beam radiotherapy alone and identified related prognostic factors.

METHODS

Patients treated with definitive external beam radiotherapy for cervical cancer unsuitable for intracavitary brachytherapy, including whole pelvic irradiation and external beam radiotherapy boost, were retrospectively examined. The endpoints were progression-free survival, overall survival and adverse events. Additionally, various patient-, tumor- and treatment-specific factors were evaluated to identify significant predictors of progression-free survival.

RESULTS

The study included 37 patients; 3 (8%), 5 (14%), 17 (46%) and 12 (32%) had clinical International Federation of Gynecology and Obstetrics (FIGO) stages I, II, III and IVA, respectively. A total radiation dose of 56-70.2 Gy was administered (84% of patients received 59.4-60.4 Gy). The median follow-up period after radiotherapy was 17 (range, 2-84) months. The progression-free survival rates at 1 and 2 years were 45 and 29%, respectively; the corresponding overall survival rates were 74 and 43%, respectively. On univariate and multivariate analyses of progression-free survival at 2 years, International Federation of Gynecology and Obstetrics stage IVA and a maximum primary tumor diameter >5 cm were associated with significantly worse outcomes (P = 0.026 and P = 0.027, respectively).

CONCLUSION

Approximately 70% of patients with cervical cancer treated with external beam radiotherapy boost instead of intracavitary brachytherapy experienced disease progression within 2 years. These results stress the necessity of devising alternative non-intracavitary brachytherapy treatment approaches, particularly for patients with International Federation of Gynecology and Obstetrics stage IVA and bulky primary tumors.

How might financial pressures have impacted brachytherapy? A proposed narrative to explain the declines in cervical and prostate brachytherapy utilization

Rates of brachytherapy administration in the United States have declined for both cervical and prostate cancers, and we argue that the available facts suggest financial considerations are a major contributor to this issue. In this narrative, we discuss financial pressures that have existed for cervical and prostate brachytherapy and how they may have influenced their declining usage, consider other proposed influences, and provide suggestions for future research to understand the scope of the issue.

What is the evidence for the clinical value of SBRT in cancer of the cervix?

AIM

The aim of this review is to describe and analyze indications and results of the use of SBRT in uterine cervix cancer, reviewing articles published from January 2010 up to August 2017, for any one of the four indications listed:1Patient refusal or anatomic impediments to interstitial or intracavitary brachytherapy (BCT), i.e. SBRT as an "alternative" for BCT;2Patients with voluminous tumors, or asymmetric tumors where BCT alone would not achieve curative doses, i.e. SBRT as a primary adjunct to BCT;3Pelvic and para aortic adenopathy where SBRT could be used as a boost, i.e. SBRT as a primary adjunct to external beam pelvic radiotherapy;4Small volume recurrences (postoperative or post radiotherapy), i.e. SBRT for salvage.

BACKGROUND

Cervix cancer standard treatment involves pelvic irradiation and chemotherapy, recent advances in irradiation techniques might offer new possible approaches.

MATERIAL AND METHODS

Systematic review of the English language literature about Cervix cancer, SBRT, published from January 2010 to January 2018 identified through a database search of PubMed, and Ovid MEDLINE, using pre-defined search phrases.

RESULTS

The results in the literature, in general, demonstrate rather weak efficacy of SBRT. In this review, we did not find strong evidence to recommend routine SBRT as a primary treatment for cervico-uterine cancers, i.e. as a replacement for BCT; in highly selected cases it might be considered useful as salvage therapy for relapsed cervix cancer.

CONCLUSION

The existing data to not warrant recommending SBRT for the definitive treatment of cervix cancer, but may have some value in the recurrent/relapsed setting.