Automated planning of curved needle channels in 3D printed patient-tailored applicators for cervical cancer brachytherapy.

Patient-tailored intracavitary/interstitial (IC/IS) brachytherapy (BT) applicators may increase dose conformity in cervical cancer patients. Current configuration planning methods in these custom applicators rely on manual specification or a small set of (straight) needles. This work introduces and validates a two-stage approach for establishing channel configurations in the 3D printed patient-tailored ARCHITECT applicator.

Assessment of integrated electromagnetic tracking for dwell position monitoring in a clinical HDR brachytherapy setting for prostate cancer.

Background: Electromagnetic Tracking (EMT) technology has been integrated in a prototype high-dose-rate brachytherapy (HDR-BT) afterloading device. Its potential for dwell position (DP) monitoring has earlier been demonstrated in prostate phantoms. However, its performance for prostate BT in the clinical setting remains to be assessed.

Dosimetric benefits and preclinical performance of steerable needles in HDR prostate brachytherapy.

Prostate cancer patients with an enlarged prostate and/or excessive pubic arch interference (PAI) are generally considered non-eligible for high-dose-rate (HDR) brachytherapy (BT). Steerable needles have been developed to make these patients eligible again. This study aims to validate the dosimetric impact and performance of steerable needles within the conventional clinical setting.

A comprehensive quality assurance protocol for electromagnetic tracking in brachytherapy.

Background: Electromagnetic tracking (EMT) systems have proven to be a valuable source of information regarding the location and geometry of applicators in patients undergoing brachytherapy (BT). As an important element of an enhanced and individualized pre-treatment verification, EMT can play a pivotal role in detecting treatment errors and uncertainties to increase patient safety.

Purpose: The purpose of this study is two-fold: to design, develop and test a dedicated measurement protocol for the use of EMT-enabled afterloaders in BT and to collect and compare the data acquired from three different radiation oncology centers in different clinical environments.

Time-action and patient experience analyses of locally advanced cervical cancer brachytherapy.

Background And Purpose: Although MRI-based image guided adaptive brachytherapy (IGABT) for locally advanced cervical cancer (LACC) has resulted in favorable outcomes, it can be logistically complex and time consuming compared to 2D image-based brachytherapy, and both physically and emotionally intensive for patients. This prospective study aims to perform time-action and patient experience analyses during IGABT to guide further improvements.

Materials And Methods: LACC patients treated with IGABT were included for the time-action (56 patients) and patient experience (29 patients) analyses.

Narrowing the difference in dose delivery for IOERT and IOBT for locally advanced and locally recurrent rectal cancer.

Purpose: Intra-operative radiotherapy (IORT) has been used as a tool to provide a high-dose radiation boost to a limited volume of patients with fixed tumors with a likelihood of microscopically involved resection margins, in order to improve local control. Two main techniques to deliver IORT include high-dose-rate (HDR) brachytherapy, termed 'intra-operative brachytherapy' (IOBT), and electrons, termed 'intra-operative electron radiotherapy' (IOERT), both having very different dose distributions. A recent paper described an improved local recurrence-free survival favoring IOBT over IOERT for patients with locally advanced or recurrent rectal cancer and microscopically irradical resections.

A Novel Framework for the Optimization of Simultaneous ThermoBrachyTherapy.

In high-dose-rate brachytherapy (HDR-BT) for prostate cancer treatment, interstitial hyperthermia (IHT) is applied to sensitize the tumor to the radiation (RT) dose, aiming at a more efficient treatment. Simultaneous application of HDR-BT and IHT is anticipated to provide maximum radiosensitization of the tumor. With this rationale, the ThermoBrachyTherapy applicators have been designed and developed, enabling simultaneous irradiation and heating.

Simultaneous ThermoBrachytherapy: Electromagnetic Simulation Methods for Fast and Accurate Adaptive Treatment Planning.

The combination of interstitial hyperthermia treatment (IHT) with high dose rate brachytherapy (HDR-BT) can improve clinical outcomes since it highly enhances the efficiency of cell kill, especially when applied simultaneously. Therefore, we have developed the ThermoBrachy applicators. To effectively apply optimal targeted IHT, treatment planning is considered essential.

Design of the novel ThermoBrachy applicators enabling simultaneous interstitial hyperthermia and high dose rate brachytherapy.

Objective: In High Dose Rate Brachytherapy for prostate cancer there is a need for a new way of increasing cancer cell kill in combination with a stable dose to the organs at risk. In this study, we propose a novel ThermoBrachy applicator that offers the unique ability to apply interstitial hyperthermia while simultaneously serving as an afterloading catheter for high dose rate brachytherapy for prostate cancer. This approach achieves a higher thermal enhancement ratio than in sequential application of radiation and hyperthermia and has the potential to decrease the overall treatment time.

An anthropomorphic deformable phantom of the vaginal wall and cavity.

Brachytherapy is a common treatment in cervical, uterine and vaginal cancer management. The technique is characterised by rapid developments in the fields of medical imaging, dosimetry planning and personalised medical device design. To reduce unnecessary burden on patients, assessments and training of these technologies should preferable be done using high-fidelity physical phantoms.

Intraoperative Electron Beam Radiation Therapy (IOERT) Versus High-Dose-Rate Intraoperative Brachytherapy (HDR-IORT) in Patients With an R1 Resection for Locally Advanced or Locally Recurrent Rectal Cancer.

Purpose: Intraoperative radiation therapy (IORT), delivered by intraoperative electron beam radiation therapy (IOERT) or high-dose-rate intraoperative brachytherapy (HDR-IORT), may reduce the local recurrence rate in patients with locally advanced and locally recurrent rectal cancer (LARC and LRRC, respectively). The aim of this study was to compare the oncological outcomes between both IORT modalities in patients with LARC or LRRC who underwent a microscopic irradical (R1) resection.

Methods: All consecutive patients who received IORT because of an R1 resection of LARC or LRRC between 2000 and 2016 in two tertiary referral centers were included.

Accuracy of dwell position detection with a combined electromagnetic tracking brachytherapy system for treatment verification in pelvic brachytherapy.

Background And Purpose: To investigate the accuracy of dwell position detection with a combined electromagnetic tracking (EMT) brachytherapy (BT) system for treatment verification, by quantifying positional errors due to EM field interference in typical pelvic BT clinical settings.

Materials And Methods: Dedicated prostate and cervix BT phantoms were imaged with CT. For the cervix phantom, the Utrecht applicator + interstitial catheters were used.

Fast and fully-automated multi-criterial treatment planning for adaptive HDR brachytherapy for locally advanced cervical cancer.

Purpose: To develop and evaluate a fast, automated multi-criterial treatment planning approach for adaptive high-dose-rate (HDR) intracavitary + interstitial brachytherapy (BT) for locally advanced cervical cancer.

Methods And Materials: Twenty-two previously delivered single fraction MRI-based HDR treatment plans (SF) were used to guide training of our in-house system for multi-criterial autoplanning, aiming for an autoplan quality superior to the training plans, while respecting the clinically desired "pear-shaped" dose distribution. Next, the configured algorithm was used to automatically generate treatment plans for 63 other fractions (SF).

Fast automated multi-criteria planning for HDR brachytherapy explored for prostate cancer.

We developed a fast and fully-automated, multi-criteria treatment planning workflow for high dose rate brachytherapy (HDR-BT). In this workflow, the patient-CT with catheter reconstructions and dwell positions are imported from the clinical TPS into a novel system for automated dwell time optimisation. The optimised dwell times are then imported into the clinical TPS.

A randomized controlled trial testing a hyaluronic acid spacer injection for skin toxicity reduction of brachytherapy accelerated partial breast irradiation (APBI): a study protocol.

Background: Accelerated partial breast irradiation (APBI) is a treatment option for selected early stage breast cancer patients. Some APBI techniques lead to skin toxicity with the skin dose as main risk factor. We hypothesize that a spacer injected between the skin and target volume reduces the skin dose and subsequent toxicity in permanent breast seed implant (PBSI) patients.

Subcutaneous spacer injection to reduce skin toxicity in breast brachytherapy: A pilot study on mastectomy specimens.

Purpose: Accelerated partial breast irradiation is a treatment option for selected patients with early-stage breast cancer. Some accelerated partial breast irradiation techniques lead to skin toxicity with the skin dose as a main risk factor. Biodegradable spacers are effective and safe in prostate brachytherapy to protect the rectum.

Fractionated high-dose-rate brachytherapy as monotherapy in prostate cancer: Does implant displacement and its correction influence acute and late toxicity?

Purpose: In fractionated high-dose-rate brachytherapy (HDR-BT) for prostate cancer (PCa) with one implant for several fractions, dose delivery relies on reproducibility of catheter positions. However, caudal displacement of implanted catheters does occur between fractions and needs to be corrected. Our protocol prescribes correction of displacements > 3 mm.

Toxicity and quality of life after high-dose-rate brachytherapy as monotherapy for low- and intermediate-risk prostate cancer.

Background And Purpose: The use of HDR brachytherapy (HDR-BT) as monotherapy for prostate cancer (PC) is increasing worldwide with good tumour control rates and acceptable toxicity. We report our results on toxicity and quality of life (QoL) after HDR-BT monotherapy for PC patients.

Materials And Methods: 166 low- and intermediate-risk localized PC patients were treated with HDR-BT to a total dose of 38Gy in four fractions.

Improving anatomical mapping of complexly deformed anatomy for external beam radiotherapy and brachytherapy dose accumulation in cervical cancer.

Purpose: In the treatment of cervical cancer, large anatomical deformations, caused by, e.g., tumor shrinkage, bladder and rectum filling changes, organ sliding, and the presence of the brachytherapy (BT) applicator, prohibit the accumulation of external beam radiotherapy (EBRT) and BT dose distributions.

Bladder function preservation with brachytherapy, external beam radiation therapy, and limited surgery in bladder cancer patients: Long-term results [corrected].

Purpose: To report long-term results of a bladder preservation strategy for muscle-invasive bladder cancer (MIBC) using external beam radiation therapy and brachytherapy/interstitial radiation therapy (IRT).

Methods And Materials: Between May 1989 and October 2011, 192 selected patients with MIBC were treated with a combined regimen of preoperative external beam radiation therapy and subsequent surgical exploration with or without partial cystectomy and insertion of source carrier tubes for afterloading IRT using low dose rate and pulsed dose rate. Data for oncologic and functional outcomes were prospectively collected.

MR guided applicator reconstruction for brachytherapy of cervical cancer using the novel titanium Rotterdam applicator.

A novel model of the titanium Rotterdam tandem and ovoid applicator is presented. As titanium produces artefacts in MR images, an MR sequence was sought and optimised for visualisation and accurate applicator reconstruction. The mean inter-observer (8 observers) variability for four patients was only 0.

Stereotactic body radiotherapy with a focal boost to the MRI-visible tumor as monotherapy for low- and intermediate-risk prostate cancer: early results.

Background: There is growing evidence that prostate cancer (PC) cells are more sensitive to high fraction dose in hypofractionation schemes. High-dose-rate (HDR) brachytherapy as monotherapy is established to be a good treatment option for PC using extremely hypofractionated schemes. This hypofractionation can also be achieved with stereotactic body radiotherapy (SBRT).