Template-based high-dose-rate interstitial brachytherapy in gynecologic cancers: A single institutional experience

Impact of MRI-based planning in transperineal interstitial brachytherapy for locally advanced cervix tumors: Clinical, dosimetric and toxicity outcomes

PURPOSE

To compare dosimetric characteristics, clinical outcomes, and toxicity in patients with locally advanced cervical cancer(LACC) treated with transperineal interstitial brachytherapy(P-ISBT), using CT-based planning or MRI-based planning with a monoinstitutional MRI-compatible applicator, Template Benidorm(TB).

MATERIALS AND METHODS

We retrospectively analyzed 106 women treated with P-ISBT for LACC from 2006 to 2022. P-ISBT was CT-based, with Martinez Universal Perineal Interstitial Template(MUPIT) between 2006 and 2012, or MRI-based planning (TB) since 2013. Volumetric, clinical, and dosimetric parameters were compared between applicators.

RESULTS

Forty-six (43.4%) patients were treated with MUPIT, and 60 (56.6%) with TB. Median follow-up was 42 months (4-188). No significant difference was observed in 5-year local control (LC), regional control (RC), distant failure (DF), overall survival (OS), and disease-specific survival (DSS) between applicators. The TB cohort had fewer needles (p = 0.001), halved median CTV volume (p < 0.001), increased median D90%CTV dose (p < 0.005), and lower D2cc values in rectum/bladder (p < 0.001). G3 chronic toxicity was 15% in the MUPIT group and 6% in TB (p = 0.15), with no G4 toxicity reported. Rectal hemorrhage was lower in the TB group (p = 0.002). Larger CTV volumes correlated with higher rectal D2cc and rectal hemorrhage (p = 0.001; p = 0.029, respectively), and enterovaginal fistula (p = 0.03; p < 0.001, respectively). Median CTV volume was 152.82 cc (35.3-256.78) in patients with chronic rectal toxicity and 102.9 cc (21.4-329.41) in those without (p = 0.001).

CONCLUSION

MRI's superior CTV-volume definition results in smaller treatment volumes, lower D2cc for rectum and bladder, and a trend towards higher CTV D90%. Rectal hemorrhage was significantly lower in the MRI-based group. A significant correlation was observed between larger CTV-volumes, higher rectal D2cc and rectal hemorrhage/enterovaginal fistula.

Image guided cervical brachytherapy practice patterns: 2023/2024 survey of the American brachytherapy society

BACKGROUND

An update of the 2007 and 2014 surveys of the American Brachytherapy Society (ABS) will elucidate current practice patterns of cervical cancer brachytherapy.

METHODS

A 40-question survey was sent to all ABS members in June-July 2023 and February 2024; 167 responses were received, with 140 used for analysis. Results were compared to the 2014 survey using chi-squared testing. Multivariable logistic regression was used to calculate adjusted odds ratios (aOR) with 95% confidence intervals (CI) for outcomes of interest.

RESULTS

Compared to 2014, MRI use for treatment planning of the first brachytherapy fraction increased from 34% to 63% (p < 0.001), prescription to the high-risk clinical target volume (HR-CTV) increased from 52% to 94% (p < 0.001), while Point A prescription decreased from 42% to 16% (p < 0.001). Additionally, procedural guidance with ultrasound significantly increased (79% vs. 32%, p < 0.001) along with the use of interstitial needles (always or nearly always, >80%) (29% vs. 4%, p < 0.001). MRI availability around the time of procedure was the largest challenge to incorporating MRI into brachytherapy treatment planning. Compared to those with MRI access reserved specifically for Radiation Oncology, respondents with shared-access or out-of-department MRI were less likely to obtain treatment planning MRIs for each brachytherapy fraction (22% vs. 75%; aOR 0.10 [95% CI, 0.03-0.30], p < 0.001).

CONCLUSION

For cervix cancer brachytherapy there has been significant increase in the use of MRI-based volumetric brachytherapy treatment planning, ultrasound guidance during procedures and the addition of interstitial needles. These advancements in practice patterns are congruent with published consensus guidelines and ongoing training initiatives. However, MRI access and lack of easy availability continue to be significant challenges for optimizing cervix brachytherapy.

Salvage radiotherapy for locally recurrent cervical and endometrial carcinoma: clinical outcomes and toxicities

BACKGROUND

The management of locally recurrent gynecological carcinoma remains a challenge due to the limited availability of data. This study aims to share our institutional experience in using definitive radiotherapy (RT) for the treatment of locally recurrent cervical and endometrial carcinoma.

METHODS

The study retrospectively reviewed 20 patients in our hospital completing salvage 3D image-based HDR brachytherapy, with or without EBRT, for locally recurrent cervical and endometrial carcinoma after surgery. The Kaplan-Meier method was applied to estimate the disease-free survival (DFS) and overall survival (OS). The toxicities were assessed by CTCAEv5.

RESULTS

During a median observation period of 21 months, the study reported a tumor objective response rate of 95%. The 3-year DFS and OS rates were 89.4% and 90.9%, respectively. The EBRT combined with brachytherapy achieved a median cumulative dose of 88 Gy to CTV D90. 14 patients received concurrent and/or systemic chemotherapy. Two patients suffered locoregional recurrence after salvage treatment, one of whom only received salvage brachytherapy for prior RT history. The analysis identified significant predictors for DFS, including tumor histology and FIGO stage. 5 patients observed acute grade 1-2 rectal (15%) or genitourinary (10%) toxicities. Late toxicities including grade 1-2 rectal bleeding (10%) and grade 2 pelvic fracture (5%) were seen in 3 patients.

CONCLUSIONS

3D image-guided brachytherapy combined with EBRT shows effective tumor control and acceptable toxicity profile for women with locally recurrent gynecologic cancer. The success in managing vaginal recurrence is notably influenced by histologic subtype and FIGO staging.

Plan quality score to evaluate the dwell time deviation restricted inverse planning by simulated annealing and graphically optimized treatment plans for template based interstitial brachytherapy

PURPOSE

To evaluate the impact of dwell time deviation constraint (DTDC) on the quality of IPSA-optimized treatment plans in comparison with graphical plans using plan quality scores (PQS).

MATERIAL AND METHODS

Seventy optimized plans (graphical & IPSA with different DTDC values) of ten cervical cancer patients were generated. Various DVH parameters like D₉₀, V₁₀₀, V₁₅₀, V₂₀₀, V₃₀₀ were compared to evaluate the impact of DTDC on target coverage and high dose regions inside target for different plans. Similarly, for the OAR dose, values of D_2cc were compared. Various planning parameters like CI, COIN, DHI, DNR, ODI, EI and gain factor (GF) for different OARs were calculated. Based on these indices a plan quality score (PQS) was formulated and calculated. PQS values were used to see the impact of DTDC on plan quality of IPSA in comparison with dosimetric quality of graphical plan.

RESULTS

We have found that target coverage is similar for IPSA and graphically optimized treatment plans. However, dose homogeneity was improved in IPSA compared to graphical optimization whereas conformality was better in graphically optimized plans. OAR dose was less in IPSA plans. High-dose regions inside the target were also reduced in IPSA comparatively. However, IPSA plans optimized with various values of DTDC did not necessarily reduce high-dose regions beyond 0.6. Plan quality scores (PQS) were 6.31, 6.31, 6.34, and 6.17 for the graphically optimized plan, IPSA with DTDC values of 0.0, 0.4, and 1.0 respectively.

CONCLUSION

We found that IPSA is dosimetrically advantageous over graphical optimization. IPSA with a DTDC value of 0.4 improved overall plan quality. However, DTDC value beyond 0.6 produces dosimetrically sub-optimal plans hence the use of DTDC should be very selective and limited.

Outcomes of 3D MRI based HDR brachytherapy with hybrid multichannel vaginal cylinder applicator and freehand needles for treatment of vaginal disease

Freehand needles can be used with multichannel vaginal cylinders (MCVC) to cover vaginal cancer >7 mm thick or with supra-vaginal extension. We report our institutional outcomes using this novel hybrid technique. Patients with vaginal malignancies treated with HDR BT using MCVC plus freehand needles from 2014-2021 at our institution were identified. Clinical characteristics, details of brachytherapy, initial response, and overall local control (LC) outcomes were recorded. LC was analyzed via Kaplan-Meier method. 34 patients were identified with median follow-up 1.9 years. 19 patients had primary endometrial cancer with vaginal recurrence/disease, and remaining had primary vaginal cancer or other primaries. 7 patients had recurrence after previous RT course. 25 patients received EBRT with median dose 45 Gy in 25 fractions, and rest received BT alone. Median HR-CTV D90 for patients treated with EBRT plus BT was 77.4 Gy. 30 patients had complete local response to BT on initial examination and/or follow-up imaging. 1 and 2-year LC rates in patients without prior RT treated with EBRT + BT were 94.1% and 94.1%, respectively. 1 and 2-year LC rates for those without prior RT were 88.1% and 76.4%, respectively. 1 and 2-year LC rates for those with prior RT were 68.6% and 34.3%, respectively. 1 patient had vaginal laceration requiring surgical repair, and 1 patient developed small bowel obstruction 1 month after BT, with no additional acute grade 3+ toxicities identified. Our approach with MCVC plus freehand needles with MRI-based planning was feasible and safe, with excellent initial local response and low rate of serious toxicities.

Dosimetric predictors of local control and complications in gynecologic transperineal implant patients: The medical college of wisconsin experience

PURPOSE

Investigate the relationship between dosimetric parameters with local control (LC) and complications following transperineal high-dose rate (HDR) interstitial brachytherapy (ISBT) for gynecologic (GYN) malignancies.

METHODS AND MATERIALS

Between 2001 and 2016, 59 patients were treated for primary or recurrent GYN malignancies. Most patients received external beam irradiation, followed by transperineal ISBT via the Syed-Neblett applicator set with CT-based planning. Treatment plans were retrospectively reviewed to evaluate for an association among LC or toxicity with the equivalent dose at 2 Gy per fraction (EQD2) for the clinical target volume (CTV), 0.1 cc (D0.1cc), and 2 cc (D2cc) volumes of the organs at risk (OAR), low/high dose volumes for the OAR and CTV, and ratio of dose at the core vs. the implant periphery.

RESULTS

The median follow-up among survivors was 24 months. 34% of patients had a component of local failure and in 12%, this was isolated. Late grade 3 (G3) toxicity occurred in 15% of patients. There were no G4-5 toxicities. Rectal D0.1cc > 75 Gy trended toward significance in predicting the development of non-fistula late G2-3 rectal complications. Bladder D0.1cc > 94 Gy significantly predicted for the development of late G2-3 vesicovaginal fistula formation. The ratio of the total dose at the vaginal surface to the needle periphery above 121% trended in predicting for any complication or fistula formation.

CONCLUSIONS

HDR ISBT combined with EBRT achieved LC in 66% of patients with advanced or recurrent GYN cancers. Rectal and bladder D0.1cc doses may be predictive of complications as may the ratio of the implant dose at the core vs. periphery.

Computed Tomography-Based Interstitial Brachytherapy for Recurrent Cervical Carcinoma in the Vaginal Apex

AIMS

To determine the factors influencing the outcomes of patients with recurrences post-hysterectomy for cervical cancers treated with external beam radiotherapy (EBRT) and interstitial brachytherapy.

MATERIALS AND METHODS

This prospective study accrued 90 patients between October 2008 and May 2014. All patients had had a prior hysterectomy and were diagnosed with recurrent vaginal apex cancers with squamous cell carcinomas. All underwent EBRT of 50 Gy (2 Gy/fraction) using tomotherapy-based image-guided intensity-modulated radiotherapy with concurrent chemotherapy of weekly cisplatin (40 mg/m²) followed by high dose rate interstitial brachytherapy boost of 20 Gy (4 Gy/fraction twice a day). Local relapse, disease-free and overall survival were determined.

RESULTS

At a median follow-up of 74 months (4-123 months), 10/90 (11%) patients had local failure as the first site of relapse and 12/90 (13.3%) had first distant relapse. Only one patient had synchronous local and distant relapse. The 7-year local relapse-free, disease-free and overall survival were 87.6, 68.3 and 68.3%, respectively. Grade 2 and 3 rectal toxicity were seen in 5.6 and 3.1% of patients, respectively. Among these, two (2.2%) patients underwent temporary diversion colostomy due to vaginal sigmoid and rectovaginal fistula. Grade 2 and 3 bladder toxicity were seen in 5.6 and 1.1% of patients, respectively. In summary, the lateral disease extent (P = 0.048) and the presence of nodal disease at diagnosis (P = 0.08) had a statistically significant or borderline impact on local relapse without any impact on disease-free survival. Tumour size in itself did not affect overall survival.

CONCLUSION

With the integration of EBRT and interstitial brachytherapy, most vaginal apex recurrences can be salvaged. An excellent local control and survival is achievable using intensity-modulated radiotherapy with image guidance and concurrent chemotherapy followed by high dose rate interstitial brachytherapy.

Changing Landscape of Radiation Therapy for Advanced Cervical Cancer With a Focus on Interstitial Brachytherapy: A Canadian Practice Patterns Survey

PURPOSE

To document the evolution of radical radiation therapy and interstitial brachytherapy (ISBT) utilization practice patterns across Canada, including use of imaging, technical details, and usage of anesthesia/analgesia, and to compare advanced (AC) versus nonadvanced (nAC) brachytherapy (BT) center practices.

METHODS AND MATERIALS

All Canadian centers with BT services were identified. One gynecology radiation oncologist per center was sent a 64-item questionnaire regarding the center's practice for patients with cervical cancer. Centers were categorized based on availability of advanced BT expertise (AC) versus those referring patients to other centers for advanced BT techniques (nAC). Aggregate responses are reported and compared with practice patterns identified in our previous survey. Descriptive statistics were used to summarize data, and the Fisher exact test, Fisher-Freeman-Halton, or Mann-Whitney-Wilcox test was used for comparisons.

RESULTS

Thirty-seven of 38 respondents completed the survey (response rate: 97.4%). Compared with 2015, there has been an increase in utilization of magnetic resonance imaging as the sole imaging modality for BT planning: 3 of 26 (11%) versus 12 of 37 (32%; P = .03). The number of centers with the ability to perform ISBT increased in 2020 compared with 2015 (26/37 [70%] vs 13/26 [50%], P = .710); this trend is likely due to an increase in use of hybrid (Vienna, Utrecht, Venezia) applicators (36% [2015] vs 84% [2020]; P = .175). Fifteen (40%) centers had the ability to perform perineal-ISBT (P-ISBT). Sixteen and 21 centers were identified as AC and nAC, respectively. All 16 AC centers had the ability to perform ISBT, compared with only 10 nAC centers (P < .001). A higher proportion of AC centers had fellowship-trained radiation oncologists performing brachytherapy, compared with nAC centers (94% vs 14%, P < .001). In terms of anesthesia, conscious sedation was the only available choice at low-patient-volume centers (8/37, 21%) performing intracavitary BT only. Those performing ISBT had choice of general, spinal, and epidural anesthesia.

CONCLUSIONS

In Canada, high-quality, modern management radiation therapy practices are consistently offered to patients with cervical cancer. There is a trend toward increased utilization of ISBT. Accumulation of evidence toward the use of ISBT, increased utilization of high-quality imaging modalities such as magnetic resonance imaging, and availability of hybrid applicators are potential contributors for this upward trend.

Dosimetry study of three-dimensional print template for 125I implantation therapy

Background

¹²⁵I seed implantation has been found to show good therapeutic effects on tumors. Recent studies showed that three-dimensional (3D) print template-assisted ¹²⁵I seed implantation can optimize radiation dose distribution. This study aimed to compare the dose distribution differences in ¹²⁵I seed implantation among 3D print noncoplanar template- (3DPNCT), 3D print coplanar template- (3DPCT) assisted implantation and traditional free-hand implantation.

Methods

We systematically searched the PubMed, EMbase, Cochrane Library, Wan Fang Med Online, China National Knowledge Infrastructure (CNKI) from the earliest to November 2020 without time or language restrictions. And the references of primary literature were also searched. The outcome measures were dosimetry and operation time. This meta-analysis was carried out using Stata 12.0.

Results

A total of 16 original articles were selected for inclusion. The differences of D90, D100, V90, and V100 values pre- and post-implantation with traditional free-hand implantation showed statistically significant (p < 0.05). The differences of D90, D100, V100, V150, V200, and D2cc of organs at risk (OAR) values pre- and post-implantation with 3D print template showed no statistically significant (p > 0.05). Compared with traditional free-hand implantation without any templates, 3D print template could improve postoperative D90 (Standard mean difference, SMD = 0.67, 95% confidence interval (CI) = 0.35 to 0.98, p < 0.001), D100 (SMD = 0.82, 95%CI = 0.40 to 1.23, p < 0.001), V90 (SMD = 1.48, 95%CI = 0.95 to 2.00, p < 0.001), V100 (SMD = 1.41, 95%CI = 0.96 to 1.86, p < 0.001), and reduce operation time (SMD = − 0.93, 95%CI = − 1.34 to − 0.51, p < 0.001). In three studies, both 3DPNCT and 3DPCT plans were designed for all patients. The prescribed dose and seed activity were same. Pooled analysis of D90, D100, V100, D2cc of OAR, number of seeds and number of needles showed no significant differences between 3DPNCT and 3DPCT groups (p > 0.05). However, in 3DPNCT group, V150 and V200 were increased (SMD = 0.35, 0.49; 95%CI = 0.04 to 0.67, 0.02 to 0.96; p = 0.028, 0.043); the number of through bone needles was reduced (SMD = − 1.03, 95%CI = − 1.43 to − 0.64, p < 0.001).

Conclusions

Compared with traditional free-hand implantation, 3D print template-assisted ¹²⁵I seeds implantation can optimize dose distribution and reduce the implantation time at the same time. Compared with 3D print coplanar template, 3D print noncoplanar template can increase the volume of high dose within tumor target and is more safer in the respect of puncture route.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13014-021-01845-y.

Brachytherapy in India: Learning from the past and looking into the future

India has a longstanding tradition in the practice of brachytherapy and has actively contributed to the scientific literature by conducting prospective studies, clinical audits, developing innovative techniques, and performing randomized studies. Indian investigators have also contributed to international collaborative research, education, training programs along with guideline development for brachytherapy in cervix and head and neck cancers. The present article summarizes the key contributions to scientific literature, current infrastructure, skill set for brachytherapy, existing challenges, and strategy to further strengthen brachytherapy practice in the next decade.

Definitive radiotherapy with image-guided adaptive brachytherapy for primary vaginal cancer

Primary vaginal cancer is a rare cancer and clinical evidence to support recommendations on its optimal management is insufficient. Because primary vaginal cancer resembles cervical cancer in many aspects, treatment strategies are mainly adopted from evidence in locally advanced cervical cancer. To date, the organ-sparing treatment of choice is definitive radiotherapy, consisting of external beam radiotherapy and brachytherapy, combined with concurrent chemotherapy. Brachytherapy is an important component of the treatment and its steep dose gradient enables the delivery of high doses of radiation to the primary tumour, while simultaneously sparing the surrounding organs at risk. The introduction of volumetric CT or MRI image-guided adaptive brachytherapy in cervical cancer has led to better pelvic control and survival, with decreased morbidity, than brachytherapy based on x-ray radiographs. MRI-based image-guided adaptive brachytherapy with superior soft-tissue contrast has also been adopted sporadically for primary vaginal cancer. This therapy has had promising results and is considered to be the state-of-the-art treatment for primary vaginal cancer in standard practice.

Brachytherapy in cervical cancer radiotherapy during COVID-19 pandemic crisis: problems and prospects

COVID-19 pandemic has adversely affected general healthcare delivery systems and cancer care throughout the world. The management of locally advanced cervical cancer presents specific challenges in this context, especially brachytherapy and completion of radiotherapy treatment, without compromising the overall treatment time and anticipated outcomes. This article presents in detail the issues and possible solutions with currently available literature for COVID-19 and radiation, in particular brachytherapy management of locally advanced cervical cancers. The review attempts to provide possible explanations and pathways based on COVID-19 testing, brachytherapy processes including application, imaging, and fractionation, keeping in mind the overall treatment time.

MRI- and PET-Guided Interstitial Brachytherapy for Postsurgical Vaginal Recurrences of Cervical Cancer: Results of Phase II Study

PURPOSE

This phase II study evaluated the utility of magnetic resonance imaging (MRI) and positron emission tomography for planning radiation and brachytherapy in patients with postsurgical recurrence of cervical cancer.

METHODS AND MATERIALS

The study (NCT01391065) recruited patients with residual or recurrent disease after hysterectomy. Patients underwent baseline T2 weighted (T2W) MRI, ¹⁸F-flouro-deoxyglucose (¹⁸F-FDG), ¹⁸F-flouro thymidine (¹⁸F-FLT) and ¹⁸F-flouromisonidazole (¹⁸F-F Miso) positron emission tomography (PET) and received external radiation (50 Gy/25 fractions for 5 weeks) and weekly cisplatin (40 mg/m²). MRI was performed at brachytherapy and used for delineation of clinical target volume (CTV). Patients with parametrial disease at baseline received interstitial brachytherapy (16-20 Gy/4-5 fractions) and those with vaginal disease received intracavitary brachytherapy (12-14 Gy/2-4 fractions). Kaplan-Meier analysis was performed to evaluate locoregional relapse, disease free survival, and overall survival. Common Toxicity Criteria for adverse event reporting (CTCAE) v4.1 was used for toxicity scoring and European Organization for Research and Treatment of Cancer (EORTC) Quality of Life Questtionaire Core 30 (QLQC-30) and Cx 24 for quality-of-life reporting.

RESULTS

Between January 2011 and February 2016, 60 patients were included, of which 50 received study treatment. The mean gross tumor volume on T2 W MR was 20 (IQR 3.6-90) cc. The metabolic tumor volume was 15 (interquartile range [IQR] 2.1-56.1) cc. The median FLT volume was 10 (IQR 0-48) cc. A total of 8 patients had ^18-F F Miso uptake. The median CTV at brachytherapy was 38 (12-85) cc. The median CTVD90 and D 98 was 71 (53-74) and 74 (53-74) Gy. At a median follow-up of 60 (5-93) months, the 5-year local control, disease free survival, and overall survival were 84%, 73%, and 74.5%, respectively. Grade III and IV proctitis and cystitis were observed in 4% and 2% of patients. On multivariate analysis baseline tumor volume, on T2 W MR impacted disease free (91% vs 65%, P = .03) and overall survival (96% vs 77%, P = .06).

CONCLUSIONS

Image-guided assisted radiation and brachytherapy are associated with good to excellent local control and survival in patients with vaginal recurrences of cervical cancer.

Indian Brachytherapy Society Guidelines for radiotherapeutic management of cervical cancer with special emphasis on high-dose-rate brachytherapy

Brachytherapy (BT) for locally advanced cervical cancer is vital for optimal outcomes. There is heterogeneity in brachytherapy treatment practice for cervical cancer across India. In an attempt to standardize various processes involved in cervical cancer brachytherapy, the expert members of the Indian Brachytherapy Society (IBS) developed a document related to radiation therapy treatment of cervical cancer with special emphasis on brachytherapy. The guidelines are based on high quality clinical evidence, expert opinion and consensus wherever evidence was lacking. The document provides a guide for external beam radiation and details of all the processes involved in high-dose-rate (HDR) brachytherapy including patient selection, preparation, principles and technique of BT applications, target and normal tissue definition, dose prescriptions, BT planning, reporting parameters, common complications of BT and their management, scope for research, etc. In summary, we present here practical tips and tricks, recording and reporting of cervical cancer brachytherapy, which can be implemented in various clinical environments and forms the basis of this report.

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.

Meeting report, “First Indian national conference on cervical cancer management - expert recommendations and identification of barriers to implementation”

Objective

In India, cervical cancer accounts for almost 14% of all female cancer cases. Although poverty continues to cast a wide net over the Indian subcontinent, the preceding three decades have borne witness to improvements in nutrition and sanitation for many citizens. However, due to an absence of a national immunization program to cover human papillomavirus (HPV) vaccination and lack of accessible cervical cancer screening, the disease is characterized by late detection, lack of access to affordable and quality health care, and high mortality rates. Treatment of cervical cancer is stage-specific and depends on the patient’s age, desire to preserve fertility, overall health, the clinician’s expertise, and accessibility to resources. There is a paucity of uniform treatment protocols for various stages of cervical cancer in India. Considering all these parameters, a need to optimize treatment paradigms for the Indian population emerged.

Methods/materials

Three expert panel meetings were held in different regions of India from 2016 to 2017. They were comprised of 15 experts from across the country, and included surgical oncologists, radiation oncologists, and medical oncologists. The panel members reviewed the literature from both national and global sources, discussed their clinical experience and local practices and evaluated current therapeutic options and management gaps for women diagnosed with cervical cancer.

Results

This article summarizes the expert opinion from these meetings. It discusses the available resources and highlights the current therapeutic options available for different cervical cancer stages: early stage disease, locally advanced tumors, recurrent/persistent/metastatic cancer. An Indian consensus governing treatment options emerged, including guidelines for use of the only approved targeted therapy in this disease, the anti-angiogenesis drug, bevacizumab.

Conclusions

The panel concluded that given the availability of state-of-the-art imaging modalities, surgical devices, radiotherapeutics, and novel agents in several population-dense urban centers, a uniform, multi-disciplinary treatment approach across patient care centers is ideal but not realistic due to cost and a paucity of third party payors for most Indian citizens. Preventative strategies including visual inspection with acetic acid to screen for precursor lesions (i.e., cervical intraepithelial neoplasia) with immediate referral for cervical cryotherapy and possible large-scale roll-out of the HPV vaccine in the near future can be expected to reduce mortality rates significantly in this country.

Cancer cervix: Establishing an evidence-based strategy, an experience of a tertiary care centre in India

Carcinoma cervix is a common cancer among Indian women. Evidence based management is essential for best practice in treatment of carcinoma cervix for its effective control. The current imaging system like CT, MRI and PET CT scans have contributed in identifying the patients for optimal treatment and delivering treatment accurately. For stages IB2 to IV, concurrent chemoradiation is advocated with improvement in overall survival proven with randomized trials. Brachytherapy is an integral part in the radiation treatment. Imaged-guided brachytherapy using MRI is desirable, however less expensive imaging modalities such as CT and ultrasonography has been evaluated. In special situation such as for HIV positive patients and patients with neuroendocrine tumors have role of radiotherapy. For further improvement in control of cancer, it is required to integrate basic research to answer clinically relevant questions.

Cervical cancer brachytherapy in Canada: A focus on interstitial brachytherapy utilization

PURPOSE

Brachytherapy (BT) techniques for cervical cancer in Canada have changed over the last decade, with evolution to high-dose-rate and image-guided BT. However, there are currently no national data on the use of interstitial BT (IBT). The purpose of this study was to document IBT utilization in Canadian centers, as well as update details of cervical cancer BT practices.

METHODS AND MATERIALS

All Canadian centers with gynecologic BT services (n = 33) were identified, and one gynecology radiation oncologist per center was sent a 33-item e-mail questionnaire regarding their center's practice for cervical cancer BT in 2015. Responses were reported and compared with practice patterns identified in a 2012 Canadian survey.

RESULTS

The response rate was 85% (28/33 centers). The majority (93%) of respondents used high-dose-rate BT, similar to the 2012 survey; 96% of centers had transitioned to three-dimensional (MRI/CT)-based planning in 2015 vs. 75% in 2012 (p = 0.03); 57% centers incorporated MRI for treatment planning in 2015 compared to 38% in 2012 (p = 0.15); the majority (13/16) using a combination of MRI and CT; 50% (14/28 centers) had the capacity to perform IBT, whereas 71% of those that did not referred patients to other centers. Of centers performing IBT, the majority (11/14) used template-based techniques with a median of 6 (range 2-20) needles/catheters and an average of 4 (range 1-5) fractions. Catheters were placed using: strategy based on pre-op imaging (21%), intra-op ultrasound (50%), intra-op MRI (7%), and intra-op CT (21%). The most common dose/fractionation schedules were 6 Gy × 5 fractions (40%), 8 Gy × 3 fractions (19%), and 7 Gy × 4 fractions (15%).

CONCLUSIONS

In Canada, treatment of cervical cancer continues to evolve. IBT has been adopted by half of the responding centers. As more centers move to MRI-based image-guided treatment planning, IBT will become an even more integral part of cervical cancer treatment.

Long term results from a prospective database on high dose rate (HDR) interstitial brachytherapy for primary cervical carcinoma

OBJECTIVE

Present long-term outcomes in primary cervical cancer treated with external beam and high dose rate interstitial brachytherapy.

METHODS

High dose rate (HDR) interstitial (IS) brachytherapy (BT) and external beam (EBRT) were administered from 1992 to 2009 to 315 patients who were unsuitable for intracavitary (IC) BT alone. Histology was 89% squamous cell, 8% adenocarcinoma, and 3% adenosquamous. FIGO stage was I-14%, II-47%, III-34%, and IVA-5%. Median tumor size was 6cm. Lymph node metastases were 26% pelvic and 9.5% para-aortic. Treatment planning was 49% 2D and 51% 3D-CT. The mean doses were central EBRT EQD210 37.3±4.3Gy (sidewall 49.2±3.6Gy) and HDR EQD210 42.3±5.3Gy (nominal 5.4Gy×6 fractions using a mean of 24 catheters and 1 tandem). Total EQD210 mean target dose was 79.5±5.4Gy. Standardized planned dose constraints were ICRU points or D0.1cc bladder 80%, rectum 75% and urethra 90% of the HDR dose per fraction. Morbidity assessment was CTCAEv3. Median and mean follow-up were 50 and 61months (3-234).

RESULTS

The 10-year actuarial local control was 87%, regional control 84%, and loco-regional control 77%. Distant metastasis free survival was 66%, cause specific survival 56%, disease free survival 54%, and overall survival 40%. The rates of late grade GU and GI toxicities were 4.8% G3 and 5.4% G4.

CONCLUSIONS

Template-guided interstitial can be safely performed to successfully deliver high radiation dose to locally advanced cervix cancer and avoid excessive dose and injury to adjacent vital pelvic organs. We achieved high tumor control with low morbidity in patients who were poor candidates for intracavitary brachytherapy.

Development and clinical implementation of a new template for MRI-based intracavitary/interstitial gynecologic brachytherapy for locally advanced cervical cancer: from CT-based MUPIT to the MRI compatible Template Benidorm. Ten years of experience

PURPOSE

To study outcome and toxicity in 59 patients with locally advanced cervix carcinoma treated with computed tomography (CT)-based Martinez universal perineal interstitial template (MUPIT) and the new magnetic resonance imaging (MRI)-compatible template Benidorm (TB).

MATERIAL AND METHODS

From December 2005 to October 2015, we retrospectively analyzed 34 patients treated with MUPIT and 25 treated with the TB. Six 4 Gy fractions were prescribed to the clinical target volume (CTV) combined with external beam radiotherapy (EBRT). The organs at risk (OARs) and the CTV were delineated by CT scan in the MUPIT implants and by MRI in the TB implants. Dosimetry was CT-based for MUPIT and exclusively MRI-based for TB. Dose values were biologically normalized to equivalent doses in 2 Gy fractions (EQD2).

RESULTS

Median CTV volumes were 163.5 cm3 for CT-based MUPIT (range 81.8-329.4 cm3) and 91.9 cm3 for MRI-based TB (range 26.2-161 cm3). Median D90 CTV (EBRT + BT) was 75.8 Gy for CT-based MUPIT (range 69-82 Gy) and 78.6 Gy for MRI-based TB (range 62.5-84.2 Gy). Median D2cm3 for the rectum was 75.3 Gy for CT-based MUPIT (range 69.8-132.1 Gy) and 69.9 Gy for MRI-based TB (range 58.3-83.7 Gy). Median D2cm3 for the bladder was 79.8 Gy for CT-based MUPIT (range 71.2-121.1 Gy) and 77.1 Gy for MRI-based TB (range 60.5-90.8 Gy). Local control (LC) was 88%. Overall survival (OS), disease free survival (DFS), and LC were not statistically significant in either group. Patients treated with CT-based MUPIT had a significantly higher percentage of rectal bleeding G3 (p = 0.040) than those treated with MRI-based TB, 13% vs. 2%.

CONCLUSIONS

Template Benidorm treatment using MRI-based dosimetry provides advantages of MRI volume definition, and allows definition of smaller volumes that result in statistically significant decreased rectal toxicity compared to that seen with CT-based MUPIT treatment.

Gynecological cancers: A summary of published Indian data

Gynecological cancers are among the most common cancers in women and hence an important public health issue. Due to the lack of cancer awareness, variable pathology, and dearth of proper screening facilities in developing countries such as India, most women report at advanced stages, adversely affecting the prognosis and clinical outcomes. Ovarian cancer has emerged as one of the most common malignancies affecting women in India and has shown an increase in the incidence rates over the years. Although cervical cancer is on a declining trend, it remains the second most common cancer in women after breast cancer. Many researchers in India have published important data in the field of gynecologic oncology, covering all domains such as basic sciences, preventive oncology, pathology, radiological imaging, and clinical outcomes. This work has given us an insight into the in-depth understanding of these cancers as well as the demographics and survival rates in the Indian population. This aim of this review is to discuss the important studies done in India for all gynecological cancers.

Weekly Cisplatin and Volumetric-Modulated Arc Therapy With Simultaneous Integrated Boost for Radical Treatment of Advanced Cervical Cancer in Elderly Patients: Feasibility and Clinical Preliminary Results

BACKGROUND

To evaluate the feasibility and clinical preliminary results of weekly cisplatin and volumetric-modulated arc therapy to the pelvis with simultaneous integrated boost to macroscopic disease in a cohort of elderly patients.

MATERIALS AND METHODS

Inclusion criteria of this prospective study were age ≥70 years, Karnofsky performance status 70 to 100, locally advanced histologically proven squamous cervical carcinoma, and patients unable to undergo brachytherapy. Radiation doses prescribed were 66 Gy to the macroscopic disease and 54 Gy to the pelvic nodes in 30 fractions. Weekly cisplatin dose was 40 mg/mq.

RESULTS

A total of 30 patients were recruited. Median follow-up was 32 months (range: 8-48 months). Median age was 72 years (range: 70-84 years). The 3-year overall survival and local control were 93% and 80%, respectively. The median time to progression was 24 months (range: 6-30 months). Analyzing clinical outcome grouping based on the stage of disease, II versus III, the 3-year overall survival was 100% and 85%, respectively. The 3-year local control was 91% for stage II and 67% for stage III. Acute and late toxicities were acceptable without severe events.

CONCLUSION

Weekly cisplatin and volumetric-modulated arc therapy-simultaneous integrated boost for radical treatment of advanced cervical cancer in the current cohort of elderly patients were feasible. Long-term results and prospective randomized trials are advocated.

Concomitant cervical and transperineal parametrial high-dose-rate brachytherapy boost for locally advanced cervical cancer

Purpose

There is no consensus for parametrial boost technic while both transvaginal and transperineal approaches are discussed. A prototype was developed consisting of a perineal template, allowing transperineal needle insertion. This study analyzed acute toxicity of concomitant cervical and transperineal parametrial high-dose-rate brachytherapy (HDRB) boost for locally advanced cervical cancer.

Material and methods

From 01.2011 to 12.2014, 33 patients (pts) presenting a locally advanced cervical cancer with parametrial invasion were treated. After the first course of external beam radiation therapy with cisplatinum, HDRB was performed combining endocavitary and interstitial technique for cervical and parametrial disease. Post-operative delineation (CTV, bladder, rectum, sigmoid) and planification were based on CT-scan/MRI. HDRB was delivered in 3-5 fractions over 2-3 consecutive days. Acute toxicities occurring within 6 months after HDRB were retrospectively reviewed.

Results

Median age was 56.4 years (27-79). Clinical stages were: T2b = 23 pts (69.7%), T3a = 1 pt (3%), T3b = 6 pts (18.2%), and T4a = 3 pts (9.1%). Median HDRB prescribed dose was 21 Gy (21-27). Median CTV_CT (16 pts) and HR-CTV_MRI (17 pts) were 52.6 cc (28.5-74.3), 31.9 cc (17.1-58), respectively. Median EQD2_αβ10 for D90_CTV and D90_HR-CTV were 82.9 Gy (78.2-96.5), 84.8 Gy (80.6-91.4), respectively. Median EQD2_αβ3 (CT/MRI) for D_2cc bladder, rectum and sigmoid were 75.5 Gy (66.6-90.9), 64.4 Gy (51.9-77.4), and 60.4 Gy (50.9-81.1), respectively. Median follow-up was 14 months (ranged 6-51). Among the 24 pts with MFU = 24 months, 2-year LRFS rate, RRFS, and OS were 86.8%, 88.8%, and 94.1%, respectively. The rates of acute genitourinary and gastrointestinal toxicities were 36% (G1 dysuria = 8 pts, G2 infection = 2 pts, G3 infection = 2 pts), and 27% (G1 diarrhea = 9 pts), respectively. One patient presented vaginal bleeding at the time of applicator withdrawal (G3-blood transfusion); no bleeding was observed due to the parametrial implant.

Conclusions

Concomitant cervical and transperineal parametrial HDRB boost for locally advanced cervical cancer appears feasible and safe with no specific acute toxicity compare to cervical HDRB alone. Longer follow-up and larger patient cohort will be needed.

Internal target volume for post-hysterectomy vaginal recurrences of cervical cancers during image-guided radiotherapy

OBJECTIVE

The outcome of post-surgical recurrences of cervical cancer may be improved through radiation dose escalation, which hinges on accurate identification and treatment of the target. The present study quantifies target motion during course of image-guided radiotherapy (IGRT) for vault cancers.

METHODS

All patients underwent planning CT simulation after bladder-filling protocol. A daily pre-treatment megavoltage CT was performed. All translations and rotations were recorded. Post-registration displacement of gross tumour volume (GTV) and centre of mass (COM) of GTV was independently recorded by two observers for fractions one to seven. Day 1 image sets served as reference images against which the displacements of COM were measured. We calculated the displacements of common volume (CV) and encompassing volume (EV) of GTV for both the observers.

RESULTS

A total of 90 image data sets of 15 patients were available for evaluation. Individual patient GTV and average GTV by both the observers were comparable. The average shifts for EV were 2.4 mm [standard deviation (SD) ±1.2] in the mediolateral, 4.2 mm (SD ±2.8) in the anteroposterior and 4.0 mm (SD ±2.1) in superoinferior directions. Similarly, the average shifts for CV were 1.9 mm (SD ±0.6) in the mediolateral, 3.7 mm (SD ±2.7) in the anteroposterior and 4.4 mm (SD ±2.7) in superoinferior directions. Using Stroom's/van Herk's formula, the minimum recommended margins would be 4.5/5.2, 8.2/9.4 and 7.3/8.3 mm, respectively, for lateral, anteroposterior and superoinferior directions.

CONCLUSION

Differential directional internal margin is recommended in patients undergoing IGRT for post-surgical recurrence of cervical cancers.

ADVANCES IN KNOWLEDGE

Internal organ motion of vault cancers can be accounted for by a directional margin to the gross tumour.

A new template for MRI-based intracavitary/interstitial gynecologic brachytherapy: design and clinical implementation

PURPOSE

To describe the potential clinical use of a new brachytherapy applicator for gynecological tumors, with special attention to locally advanced cervical carcinoma. This device allows the combination of intracavitary radiotherapy and MRI-compatible transperineal interstitial needles. The design of this template addresses the disadvantages of currently commercially available templates: the inability of the intracavitary component to reach deep into the cervix (MUPIT), and the MRI-incompatibility of these templates (MUPIT and Syed), which necessitates use of CT imaging for the dosimetry.

MATERIAL AND METHODS

The newly developed Benidorm Template applicator allows titanium needles in a template with straight and angled holes to provide different angles of divergence to be used with currently existing MRI-compatible intrauterine tubes. It can provide total coverage of the craniocaudal and lateral extension of the tumor (intrautherus, parametrial, and paravaginal). This method is mainly indicated in advanced cervical carcinoma with bulky parametrial invasion (medial or distal), with bulky primary disease that responds poorly to external beam radiotherapy extensive paravaginal involvement (tumor thickness greater than 0.5 cm) extending to the middle or lower third of the vagina, or for disease that has invaded the bladder or rectum (stage IVA).

RESULTS

Between April 2013 until December 2014, we treated 15 patients with locally advanced cervical carcinoma employing the Benidorm Template. The median dose at D90 for the CTV was 79.8 Gy (71.5-89.9 Gy), at D2cc for the bladder it was 77.6 Gy (69.8-90.8 Gy), and at D2cc for the rectum it was 71.9 Gy (58.3-83.7 Gy). Values expressed in EQD2, assuming α/β of 10 for CTV and 3 for OAR.

CONCLUSIONS

This new applicator allows the use of MRI-based dosimetry, thus providing the advantages of MRI volume definition. As such, it facilitates determination of complete intracavitary and interstitial CTV coverage and the sparing of normal tissues.

Brachytherapy in India - a long road ahead

Brachytherapy can play a very important role in the definitive cure by radiation therapy in India. However, except for in a handful of centres, the majority of hospitals use it only for intracavitary treatment. The most probable reasons for such are the lack of logistical resources in terms of trained personal and supporting staff, rather than lack of radiotherapy machines and equipment. In this article, the authors look into the various aspects of brachytherapy in India: from its beginning to present days. The authors point out the resources available, shortcomings, and some possible solutions to make use of brachytherapy more popular and effective. Apart from presenting a picture of the present scenario, the article pays attention to the positive signs of brachytherapy becoming more popular in the near future.

Reirradiation using high-dose-rate brachytherapy in recurrent carcinoma of uterine cervix

PURPOSE

To assess the feasibility of reirradiation with image-based high-dose-rate brachytherapy in previously irradiated patients with recurrent carcinoma of uterine cervix.

METHODS AND MATERIALS

Thirty previously irradiated patients diagnosed with central recurrence were treated with reirradiation. Martinez Universal Perineal Implant Template was used in 24 patients and Vienna applicator in 6 patients. Median interval between two radiation schedules was 25 months. Median delivered dose was 42 Gy equivalent dose at 2 Gy (EQD2; interquartile range, 37-46 Gy EQD2).

RESULTS

All 30 patients tolerated reirradiation well. Complete response was seen in 23 (76%) patients. With a median followup of 25 months, 2-year local control, disease-free survival, and overall survival were 44%, 42%, and 52%, respectively. Fifteen patients developed local recurrences; Local control rate was significantly higher with doses >40 Gy EQD2 (52% vs. 34%; p = 0.05). Disease-free survival was better for patients with longer interval (>25 months) between two radiotherapy schedules. Grade III radiation proctitis and cystitis was seen in 3 patients each, and Grade II small bowel toxicity was seen in 3 patients.

CONCLUSIONS

Reirradiation using high-dose-rate brachytherapy is feasible with acceptable outcomes in isolated local recurrence deemed unsuitable for surgery. The outcome is better with higher doses.