Uterine perforation - 5-year experience in 3-D image guided gynaecological brachytherapy at Institute of Oncology Ljubljana

Are prophylactic antibiotics required for combined intracavitary and interstitial brachytherapy of gynecologic cancers?

The purpose of this study is to evaluate the need for prophylactic antibiotic treatment prior to combined intracavitary and interstitial (hybrid) brachytherapy for gynecologic cancer. A total of 105 gynecologic cancer patients received 405 brachytherapy sessions, including 302 sessions of intracavitary brachytherapy and 103 sessions of hybrid brachytherapy. Prophylactic antibiotics were administered before 35% of the hybrid brachytherapy sessions. The incidence of postbrachytherapy fever and the frequency of subsequent antibiotic use for infection were compared between treatment groups. Among patients treated with hybrid brachytherapy, fever ≥37.5°C occurred in 16.4% of those not receiving prophylactic antibiotics and 16.7% of those receiving prophylactic antibiotics (P > 0.05). Similarly, fever ≥38.0°C occurred in 4.9% of patients not receiving prophylactic antibiotics and 2.4% of those receiving prophylactic antibiotics (P > 0.05). Additional antibiotics were used to treat postbrachytherapy infections in 4.8% of the group receiving prophylactic antibiotics and 0% of those not receiving prophylactic antibiotics, again without statistically significant difference. There were also no significant differences in posttreatment fever incidence and antibiotics use for infection between intracavitary brachytherapy and hybrid brachytherapy sessions. In conclusion, the incidences of infection and fever are low following hybrid brachytherapy, so prophylactic antibiotics are generally unnecessary.

Development and validation of a novel scoring system to predict the risk of uterine perforation during intracavitary brachytherapy for cervical cancer

OBJECTIVE

To develop and validate a novel scoring system for predicting the risk of uterine perforation during brachytherapy (BT) in cervical cancer patients and to stratify patients based on this score to guide the use of ultrasound guidance during BT.

METHODS

Fifty patients with uterine perforation during BT between January 2018 and December 2020 were included. Common reasons for perforation were identified and a scoring system was developed. This was then applied to a cohort of 50 patients without perforation. The 2 cohorts were compared using the χ² test. To validate the scoring system, all newly diagnosed patients who underwent BT in 2021 were scored, and analysed using χ² test and receiver operator characteristic curves.

RESULTS

The mean score in the test cohort was 10.16 (range=7-14) and 5.92 (range=5-8) for patients with and without perforation. In the validation cohort, the mean score was 6.9 (range=5-10) and 9.33 (range=7-11) for those with and without perforation. Patients with a score <8 were classified as low risk, while those with a score ≥8 were classified as high risk. Among the criteria evaluated for validation, response to external beam radiotherapy, uterine position, cervico-uterine angle (uterine flexion), identification of cervical os at BT assessment, and the total score were significant predictors, while previous history of perforation, uterine length, and additional uterine anomaly were not.

CONCLUSION

The novel scoring system is an effective predictor of perforation risk during BT. Implementing this during BT assessment can optimize the need for ultrasound guidance during the procedure.

An audit of uterine perforation and its effect on the final outcome in an academic research medical center: An optimized balance between overall treatment time and medical crisis

Purpose

Intra-cavitary brachytherapy is an integral component of cervical cancer management, and uterine perforation is the most significant complication, which may lead to prolonged overall treatment time and decreased local control in these patients.

Material and methods

A retrospective analysis of cervical cancer patients who completed radiotherapy (external beam radiotherapy and brachytherapy) in our department was conducted to determine the incidence, effect on overall treatment time, and final outcome in patients with uterine perforation during brachytherapy procedure.

Results

Among 55 women, of the 398 applications, 85 (21.36%) resulted in uterine perforation. Out of these 85 applications, treatment time was extended among 3 (3.5%) applications only, as re-insertion was done nearly after one week, while the remaining 82 (96.5%) applications were completed in time. At the time of analysis, the median follow-up was 12 months, and 32 patients were disease-free, 3 had distant metastatic disease, 2 had residual disease, and 18 were lost to follow-up.

Conclusions

In our study, uterine perforation incidence was found to be comparable with other centers worldwide. In asymptomatic and uncomplicated uterine perforation, treatment can be continued with computer-based optimized treatment plans without loading a specific dwell position and without affecting overall treatment time.

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.

IBS-GEC ESTRO-ABS recommendations for CT based contouring in image guided adaptive brachytherapy for cervical cancer

MR Imaging is regarded asthe gold standardfor Image Gudied Adaptive Brachytherapy (IGABT) for cervical cancer. However, its wide applicability is limited by its availability, logistics and financial implications. Use of alternative imaging like CTand Ultrasound (US) for IGABT has been attempted. In order to arrive at a systematic, uniform and international approach for CT based definition and contouring of target structures, GEC ESTRO, IBS and ABS agreed to jointly develop such recommendations based on the concepts and terms as published in the ICRU Report 89. The minimum requirements are clinical examination & documentation, CT or MR imaging at diagnosis and at a minimum, CT imaging with the applicator in place. The recommendations are based on (i) assessment of the GTV at diagnosis and at brachytherapy, (ii) categorizing the response to external radiation into different clinical remission patterns, (iii) defining various clinico-radiological environments and (iv) definition & delineation of a target on CT imaging at the time of brachytherapy with the applicator in situ. CT based target contouring recommendations based on 4 remission categories within 8 defined environments, aim at improving the contouring accuracy for IGABT using CT, US and MRI as available. For each clinico-radiological environment, there is an attempt to minimize the specific uncertainties in order to arrive at the best possible contouring accuracy. Evaluating feasibility & reproducibility, to achieve a benchmark towards a gold standard MR IGABT and further clinical research including outcomes with CT Based IGABT will become the next steps.

Prevention of uterine perforation during intracavitary brachytherapy of cervical cancer

Purpose

Intracavitary brachytherapy (ICBT) is a part of standard treatment for loco-regionally advanced cervical cancers. ICBT requires a tandem applicator insertion through cervical canal into uterine cavity. Accurate placement through cervical canal, which is distorted by cancer, is crucial to successful treatment. The objective of this study was to investigate actual complication rate of a Smit sleeve insertion performed by experienced gynecologists in a tertiary referral center.

Material and methods

Clinical data of 328 patients with cervical cancer treated using ICBT, between January 2013 and August 2019, were retrospectively evaluated. Predisposing factors that could have increased the risk of uterine perforation were recorded. Pre-operative ultrasound was carried out for visualization of uterine curvature and selection of an appropriate Smith sleeve length. All applications were performed by a gynecologic oncology fellow or an expert gynecologist.

Results

317 patients were suitable for analysis. Only one (0.3%) applicator placement resulted in uterine perforation. In two patients, Smit sleeve dislocated after first brachytherapy and reinserted. Adequate applicator placement was achieved, and treatment was completed as planned in 316 cases.

Conclusions

A cervical sleeve technic, which reduced the need for multiple insertions and placement of this instrument by an expert gynecologist minimize the risk of complication relative to historical controls.

Uterine perforation during brachytherapy for cervical cancer: Complications, outcomes, and best practices for forward treatment planning and management

PURPOSE

The purpose of the study was to determine the incidence of uterine perforations, review the associated complications, and propose guidelines for management of perforations after brachytherapy.

METHODS AND MATERIALS

A retrospective chart review was conducted for all patients with cervical cancer who received single or multiple high-dose-rate brachytherapy implants between April 2006 and May 2017 at a single academic institution. CT and MRI images were retrospectively evaluated to record incidences of uterine perforation of tandem during brachytherapy. Acute and long-term complications during and after treatment were scored using the Common Terminology Criteria for Adverse Events, Version 4.0, of the National Cancer Institute.

RESULTS

A total of 123 patients were included in the study. Perforations were observed in 22 patients (17.9%) with 31 (6.4%) of the 482 total implants. Of the different categories of adverse events, only the rate of acute infectious complications among those with perforations (n = 3, 13.6%) versus those without perforations (n = 3, 3.0%) was significant (p = 0.040). Two of the three perforated patients with acute infections had mild urinary tract infections, and all resolved without complications or treatment delays. The remaining one patient had a frank perforation of the anterior uterine wall with a subsequent Grade 3 pyometra infection despite administration of prophylactic antibiotics and 1-week treatment delay. This case was eventually resolved with cervical dilation and evacuation of fluid. Long-term complications were not different between the two arms.

CONCLUSIONS

Patients with cervical cancer with uterine perforations may be able to safely proceed with brachytherapy treatment without delay or need for prophylactic antibiotics in the acute setting. Further validating data would be able to assist in establishing a new standard of care and help prevent unnecessary and harmful breaks during treatment.

Computed Tomography-Guided Optimization of Needle Insertion for Combined Intracavitary/Interstitial Brachytherapy With Utrecht Applicator in Locally Advanced Cervical Cancer

PURPOSE

There are no international guidelines for optimal needle insertion during interstitial intracavitary brachytherapy (IS-ICBT) for cervical cancer. We aimed to investigate the clinical feasibility and added value of computed tomography (CT) guidance to optimize needle insertion in IS-ICBT using the Utrecht applicator and to evaluate needle shifts.

METHODS AND MATERIALS

We enrolled 24 patients who were treated with interstitial-brachytherapy. Two CT scans each were performed for every patient: (1) after applicator insertion without needles (CT_preneedle) and (2) after needle insertion (CT_postneedle). In addition to magnetic resonance imaging after external-beam radiation therapy, CT_preneedle was used to determine optimal needle locations and insertion lengths based on applicator and organs at risk positioning on the day of treatment; CT_postneedle was used for IS-ICBT planning. The needle-channel axis was used as a reference to determine needle-shift evolution.

RESULTS

A total of 266 interstitial needles were inserted in 76 of 93 BT fractions with high intra- and interpatient variations in the number of inserted needles. Based on CT_preneedle findings, needle insertion was avoided in 9, 4, 2, and 2 patients at the first, second, third, and fourth fractions, respectively. The unloaded needle frequency was 4%. Average needle contribution to total dwell time was 37.2% ± 19.2%. Shifting was observed in 68% of the needles (mean shift 2.0 ± 2.3 mm), mostly in the posterior direction, and in needles with a larger insertion length. Needle reinsertion was not needed in any patient. No complication due to needle insertion was observed, except for minor vaginal bleeding in 1 patient after needle removal.

CONCLUSIONS

The adaptive CT-guided IS-ICBT application was feasible and resulted in fewer unloaded needle insertions or complications and more efficient use with higher needle contribution to the treatment. Needle shift was frequent but did not require needle reinsertion with the proposed method.

Complications of intracavitary brachytherapy for gynecologic cancers and their management: A comprehensive review

Intracavitary gynecologic brachytherapy in the form of tandem-based brachytherapy and vaginal cylinder-based brachytherapy represents a fundamental component of the treatment of women with cervical or uterine cancer due to the ability to deliver a therapeutic dose of radiation with sharp dose falloff. This results in highly effective treatment in terms of oncologic outcomes with an overall favorable toxicity profile. Still, complications and side effects of brachytherapy do exist. While advances in brachytherapy techniques have led to a significant decrease in the rates of toxicity, a thorough understanding of the potential complications is crucial to ensuring optimal outcomes for women with gynecologic cancer undergoing brachytherapy. Use of equivalent dose at 2 Gy per fraction (EQD2) models has allowed incorporation of external beam radiotherapy dose to the brachytherapy dose leading to development of consolidated dose constraints for organs-at-risk in the modern era. This manuscript offers a comprehensive review of potential complications associated with intracavitary brachytherapy for gynecologic cancer including predictive factors, mitigation tactics, and management strategies.

Post-radiation Mullerian adenosarcoma with sarcomatous overgrowth: rare presentation of an uncommon malignancy

Mullerian adenosarcoma is an uncommon biphasic malignant uterine tumor. It is composed of benign epithelial and malignant stromal elements. We present a case of a 45-year-old woman who presented with post-menopausal bleeding for three months. She had a significant past medical history of pelvic irradiation for squamous carcinoma of cervix 20 years ago. Pathology revealed adenosarcoma with sarcomatous overgrowth. The patient had a recurrence of pure sarcoma three months later and unfortunately succumbed to her disease. The role of radiation in the pathogenesis of adenosarcoma has been uncommonly described compared to its well established role in the development of carcinosarcoma. Our case fulfils the criteria for a radiation induced sarcoma. We review the salient clinical and pathological features of this uncommon lesion highlighting the importance of sarcomatous overgrowth in these lesions and the possible role of radiation in the development of these tumors.

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.

Radiation Dose in the Uterine Perforation by Tandem in 3-Dimensional Cervical Cancer Brachytherapy

Cervical cancer patients may sometimes experience different types of uterine perforation by a tandem during brachytherapy. The purpose of this study was to address possibly different management strategies regarding different tandem positions from a dosimetry aspect by evaluating radiation doses delivered to organs-at-risk (OAR) in order to help medical professionals handle different types of uterine perforation. Images and dosimetry data in cervical cancer brachytherapy with uterine perforation were reviewed. Uterine perforation was classified into anterior and posterior perforation according to their tandem positions. Radiation doses received by OAR, including D_2cc and D_1cc of the bladder, rectum, and sigmoid colon, were statistically compared with nonperforation. The doses of high-risk clinical target volume (HR-CTV) of cervical tumor and bilateral point A were also compared in order to assure that the plans had not compromised the treatment efficacy. A total of 21 applications were assessed, including 5 with anterior perforation, 4 with posterior perforation, and 12 without perforation. In anterior perforation, the bladder was the only organ that received a significantly increased dose about 30% at D_2cc and D_1cc. However, in posterior perforation, multiple OAR received significantly excessive doses: approximately 30% for the bladder, 37% for the rectum, and 100% for the sigmoid colon. The OAR dose assessment was based on a statistically equivalent cervical tumor dose. Different management strategies are possible for anterior vs posterior perforation during brachytherapy due to different detrimental extents on OAR dosimetry. The bladder warrants more attention in anterior perforation, without compromising target coverage in treatment planning. On the other hand, repositioning may be considered in posterior perforation due to relatively massive OAR detriments. This concept is a new one and is given for the first time.

Comparison of impact of target delineation of computed tomography- and magnetic resonance imaging-guided brachytherapy on dose distribution in cervical cancer

Purpose

The dose distributions obtained from three imaging approaches for target delineation in cervical cancer using high-dose-rate (HDR) brachytherapy were investigated.

Material and methods

Ten cervical cancer patients receiving four fractions of HDR brachytherapy were enrolled. Based on different imaging approaches, three brachytherapy plans were developed for each patient: with the high-risk clinical target volume (HRCTV) delineated on magnetic resonance (MRI) images for every fraction (approach A; MRI-only); on MRI for the first fraction and computed tomography (CT) images for the subsequent fractions (approach B; MRI_1st/CT); and on CT images for all fractions (approach C; CT-only). The volume, height, width at point A, width at maximum level, and dosimetric parameters (D₁₀₀, D₉₈, D₉₅, and D₉₀ of the HRCTV; and D_0.1cc, D_1cc, and D_2cc of all organs at risk, or organ at risk – OAR: bladder, rectum, sigmoid colon, and bowel) provided by each approach were compared.

Results

The mean HRCTV volume, width, and height obtained from approach C (CT-only) were overestimated compared to those from approaches A (MRI-only) and B (MRI_1st/CT). The doses to the HRCTV for approaches A and B were similar. However, the HRCTV doses for approach C were significantly lower than those for approaches A and B for all parameters (D₉₅-D₁₀₀). As to the OAR, the three approaches showed no differences.

Conclusions

A combination of MRI and CT is a safe alternative approach for cervical cancer HDR brachytherapy. The technique provides comparable dosimetric outcomes to MRI-based planning, while being more cost-effective.

Incidence of Suboptimal Applicator Placement and the Resulting Dosimetric Impact in Image-Based Intracavitary Brachytherapy

Aim

With the advent of computed tomography (CT)-based brachytherapy, it is possible to view the appropriate placement of the applicator within the uterine canal and detect uterine perforation. In this study, the incidence of suboptimal placement of the intracavitary applicator and the resulting dosimetric impact were analyzed and compared with a similar set of ideal applicator placement.

Materials and Methods

CT datasets of 282 (141 patients) high dose rate brachytherapy insertions between January and April 2016 were analyzed. The target volumes and organs at risk (OAR) were contoured as per the Groupe Européen de Curiethérapie European Society of Therapeutic Radiation Oncology guidelines. The position of the applicator in the uterine cavity was analyzed for each application.

Results

The suboptimal insertion rate was 11.7%. There were 26 perforations and 7 subserosal insertions. The most common site of perforation was through the posterior wall of the uterus (42.4%). Fundus perforation and anterior wall perforation were seen in 24.2% and 12.1% of patients, respectively. The average dose to 90% of the target volume (D90 to high-risk clinical target volume) was the highest (9.15 Gy) with fundal perforation. Average dose to 2 cc (D2cc) bladder was highest for fundus perforation (7.65 Gy). The average dose received by 2 cc of rectum (D2cc) was highest (4.49 Gy) with posterior wall perforation. The average D2cc of the sigmoid was highest with anterior perforation (3.18 Gy).

Conclusion

In order to achieve better local control and to decrease doses to OAR, it is important to perform a technically accurate applicator placement. A cost-effective, real-time image guidance modality like ultrasound is recommended for all insertions to ensure optimal applicator insertion.

Off-line magnetic resonance imaging navigation of cervix cancer brachytherapy in patients with risk factors for uterine perforation

Purpose

There are no reports on pre-insertion identification of cervix cancer patients at risk for uterine perforation during brachytherapy (BT). Our aim was to assess the incidence of risk factors in our patient cohort, and assess feasibility of a novel technique of magnetic resonance imaging (MRI)-guided navigation for applicator insertion (NAI) in high-risk cases.

Material and methods

All patients with locally advanced cervical cancer, treated with image guided adaptive BT at our department between October 2013 and June 2017 were considered for analysis. Tumor characteristics on initial MRI (MRI_initial), pre-BT MRI (MRI_pre-BT), and BT MRI (MRI_BT) were assessed. Frequency of risk factors (age above 60 years, retroverted/retroflected uterus, tumor necrosis, non-visible cervical orifice, distorted cervical canal) was recorded. Patients with two or more factors underwent MRI guided NAI. Time needed for NAI was estimated and procedure feasibility score assigned using a three-tiered scoring system.

Results

Twenty-seven patients (98 insertions) were included. Mean tumor volume was 70.2 (± 47.9), 17.8 (± 18.9), and 10.3 (± 9.1) cm³ on MRI_initial, MRI_pre-BT, and MRI_BT1, respectively (p < 0.05). In 16 (59%) cases, ≥ 1 perforation risk factor was found on MRI_pre-BT: distorted canal in 12 (44%), necrosis in 9 (33%), retroverted/retroflected uterus in 8 (30%) cases. Nine (33%) patients had ≥ 2 risk factors and underwent MRI guided NAI. Additional time to perform NAI was estimated at 105 minutes, and feasibility score was 1 in all cases. There were no cases of uterine perforation.

Conclusions

Using pre-insertion MRI, we found ≥ 2 risk factors for uterine perforation in 1/3 of patients. Off-line MRI navigation was feasible and enabled non-complicated insertion in all cases. Further studies with larger sample size are warranted to assess its clinical efficacy.

Intraoperative sonographic guidance for intracavitary brachytherapy of cervical cancer

BACKGROUND

To describe the role and benefits of intraoperative sonographic (US) guidance in intracavitary brachytherapy of cervical cancer.

METHODS

The data of 142 patients who received tandem-based intracavitary brachytherapy for cervical cancer between January 2010 and June 2015 were retrospectively reviewed. US guidance was carried out for tandem selection and appropriate application. The complications and applicator conformity were assessed with planning CT.

RESULTS

Intracavitary brachytherapy was performed under US guidance for 412 insertions in 113 consecutive patients with cervical cancer. Before we started to use US guidance, applications were done in 29 patients: uterine perforation occurred in two patients (6.9%), the tandem length was short in two patients (6.9%), the tandem length was long in four patients (13.8%), and tandem was in myometrium in three patients (10.3%). We then decided to use US guidance routinely. With US guidance, only 1 of 113 patients had uterine perforation (0.9%), tandem length was short in only one patient (0.9%), and tandem was in myometrium in one patient (0.9%).

CONCLUSIONS

Real-time US provided safe and effective guidance for intracavitary brachytherapy of cervical cancer resulting in decreased rates of perforations and misplacement of applicators. © 2017 Wiley Periodicals, Inc. J Clin Ultrasound 46:8-13, 2018.

Potential role of TRAns Cervical Endosonography (TRACE) in brachytherapy of cervical cancer: proof of concept

PURPOSE

Magnetic resonance imaging (MRI) is the gold standard for image guided adaptive brachytherapy (BT) of cervical cancer. Ultrasound is an attractive alternative with reasonable costs and high soft tissue depiction quality. This technical note aims to demonstrate the proof of principle for use of TRAns Cervical Endosonography with rotating transducer in the context of brachytherapy (TRACE BT).

MATERIAL AND METHODS

TRACE BT presentation is based on a single stage IIB cervical cancer patient. Prior to second BT implant, rotating US transducer (6.9 mm diameter) was inserted in cervical canal and axial images obtained at 10 MHz, focal range of 30 mm, and axial resolution of 0.4 mm. Size and topography of hypo-echoic areas were assessed and optimal positions of interstitial needles were determined. Finally, intracavitary applicator was placed and needles inserted through vaginal ring-template according to TRACE pre-plan. MRI-based high risk clinical target volume (CTVHR) dimensions were compared with hypoechoic areas on TRACE. Topography of parametrial needles on post-insertion MRI was compared with TRACE pre-plan.

RESULTS

Insertion of rotating mechanism into cervico-uterine cavity was safe, feasible and fast. The 360° imaging in axial plane enabled real-time assessment of cervix, uterus, and adjacent parametria. Qualitative comparison of TRACE with post-insertion MRI revealed favorable agreement of findings. In-plane size of CTVHR on MRI was comparable to hypoechoic areas on TRACE. Needle positions on post-insertion MRI corresponded to TRACE-based pre-plan. Main limitation of TRACE was gradual deterioration of image quality due to coupling gel removal.

CONCLUSIONS

Present proof of concept demonstrates potential role of TRACE-BT for cervical cancer as an attractive high-tech approach with reasonable costs. Prior to investigation of its clinical role, further development of TRACE methodology is needed. This includes reliable transducer-tissue coupling, applicator reconstruction, imaging range, limitations in extensive tumors, US-based contouring concepts, registration with other imaging methods, organ dose-assessment, real-time dosimetry, etc.

Brachytherapy in pelvic malignancies: a review for radiologists

Brachytherapy, also known as sealed source or internal radiation therapy, involves placement of a radioactive source immediately adjacent to or within tumor, thus enabling delivery of a localized high dose of radiation. Compared with external beam radiation which must first pass through non-target tissues, brachytherapy results in less radiation dose to normal tissues. In the past decade, brachytherapy use has markedly increased, thus radiologists are encountering brachytherapy devices and their associated post-treatment changes to increasing degree. This review will present a variety of brachytherapy devices that radiologists may encounter during diagnostic pelvic imaging with a focus on prostate and gynecologic malignancies. The reader will become familiar with the function, correct position, and potential complications of brachytherapy devices in an effort to improve diagnostic reporting and communication with clinicians.

Consensus statement for brachytherapy for the treatment of medically inoperable endometrial cancer

PURPOSE

The purpose of this consensus statement from the American Brachytherapy Society (ABS) is to summarize recent advances and to generate general guidelines for the management of medically inoperable endometrial cancer patients with radiation therapy.

METHODS

Recent advances in the literature were summarized and reviewed by a panel of experts. Panel members participated in a series of conference calls and were surveyed to determine their current practices and patterns. This document was reviewed and approved by the full panel, the ABS Board of Directors and the ACR Commission on Radiation Oncology.

RESULTS

A transition from two-dimensional (2D) to three-dimensional (3D) treatment planning for the definitive treatment of medically inoperable endometrial cancer is described. Magnetic resonance (MR) imaging can be used to define the gross tumor volume (GTV), clinical target volume (CTV), and the organs at risk (OARs). Brachytherapy alone can be used for medically inoperable endometrial cancer patients with clinical Stage I cancer with no lymph node involvement and no evidence of deep invasion of the myometrium on MR imaging. In the absence of MR imaging, a combined approach using external beam and brachytherapy may be considered.

CONCLUSIONS

Recent advances support the use of MR imaging and 3D planning for brachytherapy treatment for medically inoperable endometrial cancer.

Uterine perforation and its dosimetric implications in cervical cancer high-dose-rate brachytherapy

Purpose

To retrospectively assess the incidence of sub-serosal and uterine perforation of intra-uterine tandem in intracavitary high-dose-rate (HDR) brachytherapy for cervical cancer, and to evaluate its dosimetric implications on computed tomography (CT)-based treatment planning.

Material and methods

Computed tomography images and brachytherapy plans of cervical cancer patients treated from February 2006 to December 2012 were reviewed for sub-optimal implants (sub-serosal and uterine perforation), and their correlation with cancer FIGO stage and patients’ age. For each patient, the plans showing sub-optimal insertion of intra-uterine tandem were analyzed and compared to plans with adequate insertion. The difference in dose coverage of clinical-target-volume (CTV) and variation of the dose delivered to organs-at-risk (OARs) rectum and bladder were evaluated.

Results

A total of 231 brachytherapy plans for 82 patients were reviewed. We identified 12 (14.6%) patients and 14 (6%) applications with uterine perforation, and 12 (14.6%) patients and 20 (8.6%) applications with sub-serosal insertion of tandem. Data analysis showed that advanced stage correlates with higher incidence of sub-optimal implants (p = 0.005) but not the age (p = 0.18). Dose-volume-histograms (DVHs) analysis showed large variations for CTV dose coverage: D₉₀ significantly decreased with average of –115.7% ± 134.9% for uterine perforation and –65.2% ± 82.8% for sub-serosal insertion (p = 0.025). The rectum and bladder dose assessed by D_2cc increased up to 70.3% and 43.8%, respectively, when sub-optimal insertion of uterine tandem occurred.

Conclusions

We report a low incidence of uterine perforation and sub-serosal insertion of uterine tandem in intracavitary HDR brachytherapy for cervical cancer. However, the effects on treatment plan dosimetry can be considerably detrimental. Therefore, we recommend image-guided insertion, at least for the challenging cases.

Uterine perforation during 3-dimensional image-guided brachytherapy in patients with cervical cancer: Baskent University experience

OBJECTIVES

This study aimed to determine the incidence and characteristics of uterine perforation at our department using 3-dimensional computed tomography (CT)-based brachytherapy (BRT). The characteristics of the patients presenting with perforation and impact of the perforation on the treatment course were also analyzed.

MATERIALS AND METHODS

The clinical and radiologic data of 200 patients with biopsy-proven cervical cancer treated using CT-based BRT were retrospectively evaluated. All patients had undergone tandem-based intracavitary BRT, and 67 patients had undergone magnetic resonance imaging (MRI) before BRT.

RESULTS

Of the 200 patients, 17 (8.5%) had uterine perforation. Of the 626 applications with CT images, 30 (4.8%) resulted in uterine perforation. The median age of patients with perforation was higher (68 years; range, 44-89 years) than that of the patients without perforation (59 years; range, 21-87 years), and the mean (SD) tumor size at diagnosis was larger in patients with perforation (7.0 [1.5] cm) than in patients without perforation (5.0 [1.5] cm). The most frequent perforation site was the posterior uterine wall (8 patients), followed by the fundus (5 patients) and anterior wall (4 patients). Of the 7 patients with a retroverted uterus, 4 had uterine perforation during BRT. In 67 patients with MRI delivered before BRT, only 3 (4%) had uterine perforation, and 2 of the 3 patients with uterine perforation had a retroverted uterus. However, of the 133 patients with no MRI evaluation before BRT, 14 (11%) had uterine perforation. No life-threatening complications or signs of intraperitoneal tumor cell seeding were observed.

CONCLUSIONS

Older age, larger tumors, a retroverted uterus, and a stenotic cervical os were all predisposing factors for uterine perforation during BRT. Preoperative MRI is a feasible and safe method to decrease the risks of uterine perforation and could be used preoperatively in centers where intraoperative ultrasonography is not used in routine practice.

Acute complications following intracavitary high-dose-rate brachytherapy in uterine cancer

Purpose

Almost 30% of malignancies in women of developing countries are gynecological and brachytherapy is an integral part of management of these patients. Reports of complications (both acute and late) of high-dose-rate (HDR) intracavitary brachytherapy are sparse in world literature due to relatively small number of gynecological malignancies, particularly in advanced stage, in developed countries. High-dose-rate brachytherapy is gaining popularity in developing countries due to scientific and economic reasons. Here we are reporting our experience regarding acute complications of intracavitary brachytherapy (events occurring within 30 days of insertion needing hospitalization or death) and their causes to improve the quality of management, so that the already low incidence of acute complications can be further reduced.

Material and methods

From February 2004 to December 2012, a total of 1947 patients with uterine cancer were treated by HDR intracavitary brachytherapy in the Department of Radiotherapy, of a tertiary cancer centre of a developing country, 86% of them were cervical cancer and 14% endometrial cancer. Excluding the post-operative patients, a total of 4285 insertions were done in 1527 patients with intact uterus (eligible for analysis) and acute complications were analyzed.

Results

Out of 4285 intracavitary brachytherapy insertions in gynecological malignancy patients, only 12 mortality and 239 morbidity instances needing hospitalization were documented and most of them were in cervical carcinoma patients.

Conclusions

Our results have indicated that acute complications can be minimized by pre-treatment management of co-morbidities, decreasing the time of operative lithotomy position and bed rest, avoidance of ‘conscious sedation’ in selected cases etc. Routine post insertion CT scan if done in all patients in all insertions, then only, uterine perforations can be detected early and prompt management can reduce both the mortality and morbidity to a great extent.

Inter-application displacement of brachytherapy dose received by the bladder and rectum of the patients with inoperable cervical cancer

BACKGROUND

The aim of the study was to examine on the CT basis the inter-application displacement of the positions D0.1cc, D1cc and D2cc of the brachytherapy dose applied to the bladder and rectum of the patients with inoperable cervical cancer.

PATIENTS AND METHODS

This prospective study included 30 patients with cervical cancer who were treated by concomitant chemo-radiotherapy. HDR intracavitary brachytherapy was made by the applicators type Fletcher tandem and ovoids. For each brachytherapy application the position D0.1cc was determined of the bladder and rectum that receive a brachytherapty dose. Then, based on the X, Y, and Z axis displacement, inter-application mean X, Y, and Z axis displacements were calculated as well as their displacement vectors (R). It has been analyzed whether there is statistically significant difference in inter-application displacement of the position of the brachytherapy dose D0.1cc, D1cc and D2cc of the bladder and rectum. The ANOVA test and post-hoc analysis by Tukey method were used for testing statistical importance of differences among the groups analyzed. The difference among the groups analyzed was considered significant if p < 0.05.

RESULTS

There are significant inter-application displacements of the position of the brachytherapy dose D0,1cc, D1cc and D2cc of the bladder and rectum.

CONCLUSIONS

When we calculate the cumulative brachytherapy dose by summing up D0,1cc, D1cc and D2cc of the organs at risk for all the applications, we must bear in mind their inter-application displacement, and the fact that it is less likely that the worst scenario would indeed happen.

MRI findings at image guided adaptive cervix cancer brachytherapy: radiation oncologist's perspective

Magnetic resonance imaging (MRI) represents the reference imaging modality for image guided adaptive brachytherapy (IGABT) of cervix cancer. Accurate interpretation of pre-treatment MRI is required for proper understanding of the tumor extent and topography at IGABT. Planning and optimal timing of the application begins already before treatment, and may need to be adapted during external beam irradiation (EBRT) according to additional clinical and/or radiological findings. The level of MRI utilization in IGABT depends on the infrastructural capabilities of individual centers, ranging from no use at all to repetitive imaging during EBRT and each IGABT fraction. In this article, we summarize the role of different imaging modalities and practical aspects of MRI interpretation in cervix cancer IGABT, concentrating on the systematic evaluation of post-insertion images. MRI with the applicator in place from the radiation oncologist’s perspective should begin with immediate identification of eventual complications of the application procedure and assessment of the implant adequacy, followed by appropriate corrective measures in case of adverse findings. Finally, the tumor extent, topography, and treatment response should be evaluated in the context of initial clinical and radiological findings to allow for an appropriate selection and delineation of the target volumes.