A study from MedUni Vienna and Vienna General Hospital has demonstrated the benefits of a targeted approach in brachytherapy to treat cervical cancer.
Researchers from MedUni Vienna’s Comprehensive Cancer used data from the multicentre EMBRACE-I trial to support their findings. The research could provide a basis for customised treatment plans for cancer patients.
Of all the cancers, cervical cancer has the fourth highest mortality rate among women worldwide. Locally advanced cervical cancer (LACC) is usually treated through a combination of external and internal radiotherapy, known as brachytherapy, and chemotherapy.
What is brachytherapy?
Brachytherapy is a special type of radiation oncology procedure in where an applicator is inserted directly into or in the immediate vicinity of the cancer tumour. This is as part of a minimally invasive procedure, and the tumour is then irradiated internally using a computerised remote control.
The Embrace-I study, was completed at the Department of Radiation Oncology at MedUni Vienna and Vienna General Hospital at the Comprehensive Cancer Center. In the study, researchers personalised brachytherapy for cervical cancer as part of an international consortium with 24 research centres across Europe, Asia and North America.
Instead of using the typical method of brachytherapy, where the same dose is applied to everyone, regardless of the individual tumour spread, the researchers created an innovative personalised treatment concept.
“This analysis showed that the precise adaptation of the dose according to the tumour volume defined by magnetic resonance imaging is relevant for tumour control. Hypothetical assumptions could thus be clinically confirmed in an international group of more than 1,300 patients,” described the study leaders Maximilian Schmid and Christian Kirisits from the Department of Radiation Oncology.
The researchers were able to identify risk factors from the data from the Embrace-I study and correlate them with the brachytherapy doses.
“This is the first time we have seen that different brachytherapy doses are required for individual parameters such as different histologies or different tumour sizes,” explained Schmid.
The researchers conducted a follow-up study where they investigated a risk-adapted customised treatment. In this treatment, a lower dose is administered in a low-risk situation and was therefore presumably safer. Then a higher dose was administered in a higher-risk situation, helping to achieve reliable long-term tumour clearance.
“In the future, the new findings will allow us to offer patients customised targeted therapy,” said Schmid.
Personalised plans could eradicate the need for surgery
The researchers made another key finding. In addition to the 98% tumour remission rate and the 92% high local tumour control rate of the uterus after five years, 81 out of the 1318, patients still had a residual tumour three months after the therapy ended.
In three-quarters of these 81 patients, the tumour disappeared after another three to six months without any further therapy. Only in 21 patients did the tumour require further treatment after this period.
“Previously, it was common to perform surgery after three months at the latest if the tumour remained. Obviously, this is not necessary for a large proportion of patients. We can conclude from this study that a tumour that is still visible three months after the end of therapy can also only be observed by means of gynaecological examination and magnetic resonance imaging if it has already shrunk,” the researchers concluded.
