An innovative radiotherapy technique benefits patients with locally advanced cervical cancer

Patients with locally advanced cervical cancer benefit significantly from an innovative radiotherapy technique co-developed by MedUni Vienna under the direction of Richard Pötter and Christian Kirisits. The technique provides better tumor control and produces fewer side effects. This is confirmed by the results of the prospective, international and multicenter study, EMBRACE I, conducted under the direction of the Oncological Radiotherapy Department of the Comprehensive Cancer Center (CCC) of MedUni Vienna and the Vienna General Hospital. The results will be presented at the European Radiation Oncology Conference which was supposed to be held in Vienna and is now taking place as an online event. This will provide the world’s first reliable data on a personalized radiation oncology treatment concept for cervical cancer.

In Austria, around 400 women a year develop cervical cancer and 150 die from the disease over the same period. Globally, cervical cancer has the fourth highest death rate of all cancers in women. Standard treatment is early stage surgery. In the locally advanced stage, when the tumor has exceeded a certain size or has broken through the organ boundary but before metastases are present, a combination of external beam radiation therapy and chemotherapy that reduces the size of the tumor is used. The residual tumor is then treated with brachytherapy.

It is a radiotherapy technique, in which a source of radiation is temporarily inserted into the uterus via an applicator, with a minimally invasive procedure. The radiation source can be placed through the applicator in the desired location via the remote control of the computer, thus directly treating the tumor.

Focused and personalized

In the context of EMBRACE I (www.embracestudy.dk), a working group from the Department of Oncological Radiotherapy of MedUni Vienna and the Vienna General Hospital investigated ways to improve this technique. This involved the treatment and observation of 1,341 cervical cancer patients over a period of 10 years in 24 specialized centers around the world, under the direction of the Vienna working group in collaboration with a team from Aarhus (Denmark).

In the EMBRACE I study, radiation therapy was planned using magnetic resonance imaging (MRI). Compared to previously used radiographic images, MRI provides highly accurate images of the tumor and surrounding organs, thus facilitating personalized and targeted treatment. The tumor can be accurately identified in relation to the applicator allowing for the exact positioning of the radiation source, which leads to a higher dose to the tumor and a reduced dose to the surrounding organs.

Impressive results

The results are clear: in 92% of the cases treated with the MRI technique, the primary tumor could no longer be detected in the region of the cervix (“local tumor control”) even five years after treatment. It is especially patients with advanced tumors (Stage IIIB) who benefit from this innovative technique. In this stage of the tumor, an improvement of more than 15% was observed compared to the previous study (RetroEMBRACE). The rate was then still only 75%.

Improvements in local tumor control also appear to be directly associated with improved overall survival: a five-year survival rate of 74% was found for a total of 1,341 patients (9% improvement). The researchers were also able to show that even when the tumor has grown into the bladder (Stage IVA) and lymph node metastases are present along the large abdominal vessels (“para-aortic”, Stage IVB), there is a possibility healing (five-year survival of 52% and 61% respectively).

We have successfully demonstrated that a personalized therapeutic approach is feasible in radiotherapy for cervical cancer. The concept is so impressive that, based on our work, it will be adopted around the world. “

Maximilian Schmid of the Vienna Working Group

The results of the EMBRACE I study are currently under further review in a follow-up study entitled “EMBRACE II”. This will seek a specific radiation dose and systematic treatment of lymph node metastases, particularly para-aortic ones, with the aim of reducing the rate of relapses there. More than 600 patients have already been included in EMBRACE II.

EMBRACE III is also in the planning stage and this study will begin in early 2022 to examine further personalization of treatment based on the patient’s risk profile. Attention is expected to focus on combating lymph nodes and remote metastases in high-risk patients (e.g. through a combination of radio-chemotherapy and antibodies and / or immunotherapies). For low-risk patients, the intensity of treatment can be reduced to minimize treatment-associated side effects.