University of Newcastle
Senior Medical Physicist
Dean of Health Sciences
University of Newcastle
Large international studies such as RetroEMBRACE and EMBRACE have analyzed clinical and dosimetric data from brachytherapy treatments for cervical cancer. Unfortunately no departments in our region participated in these studies. Several Australian centres have enrolled in EMBRACE II however this is a prescriptive study that has limited imaging and dosimetric flexibility. The present study aimed to review treatment practices, clinical patient information and dosimetric data from local Australasian departments.
Materials and Methods:
All centres performing cervical HDR brachytherapy were invited to participate in the study. Each centre was provided with a worksheet to be completed for a cross-section of de-identified cervical cancer patients treated at that department. Data requested included:
- patient demographics
- treatment practices: external beam treatment technique, timing of HDR brachytherapy, treatment applicator and imaging used for HDR treatment planning
- dosimetry: external beam radiation dose/fractionation, HR-CTV, Point A, bladder, rectum, sigmoid and vaginal mucosa dose as well as total reference air kerma (TRAK)
Data was analyzed for trends and statistics across all patient information provided. Outliers were contacted to provide additional information in order to better classify results.
Approximately 70% of departments contacted provided data for this study. The average age of treated patients was 49.9 years (range 25 to 88 years) with over half of patients diagnosed with squamous cell carcinoma of the cervix of FIGO stage IIB. Over 95% of patients saw no local recurrence during the follow up period (range 0 to 630 weeks) and almost 80% of patients also had no distant disease or complications.
Most patients were treated once daily, with 66% of patients being treated in 3 fractions. Almost 90% of departments that responded used volumetric-based prescriptions and 67% of departments use some form of magnetic resonance imaging as part of HDR treatment planning. More than half of the patients had a tandem/ovoid-type applicator inserted for treatment.
On average, patients met EMBRACE II planning criteria for the target, bladder, rectum and sigmoid. Approximately half of the departments that responded were also routinely reporting vaginal mucosa dose.
Australia and New Zealand radiation oncology departments have “embraced” volumetric planning and advanced imaging techniques for HDR brachytherapy treatments of cervical cancer. Almost all departments in Australia and New Zealand are meeting the GEC-ESTRO/ABS dosimetric planning aims for both the HR-CTV and organs at risk and this is reflected in the clinical outcomes for these patients.