Promising results of clinical trial of radiotherapy for patients with mesothelioma announced


Researchers trialing a higher dose of treatment in patients with mesothelioma, as part of the SYSTEMS-2 clinical trial, found a significant increase in life expectancy in the patients who received the higher dose of radiotherapy, according to preliminary results announced at the British Thoracic Oncology Group’s (BTOG) annual conference.

SYSTEMS-2 is a randomised phase II study of standard versus a higher dose of radiotherapy for the treatment of pain in malignant pleural mesothelioma. The main aim of the trial was to see if the escalated dose works better to manage pain, which is an important problem in patients with this type of cancer. The researchers also monitored the side-effects of treatment and the life expectancy of patients treated in the trial.

Although the higher dose radiotherapy was associated with a small increase in the number of patients experiencing pain control, the difference was not statistically significant. However, the researchers were surprised to find a significant increase in life expectancy in the patients who received the higher dose of treatment. With many of the trial patients still being followed up, the study team are planning to review the results later in the year.

Professor Anthony Chalmers, Chair of Clinical Oncology at the University of Glasgow and Chief Investigator for the study commented: "SYSTEMS-2 is the first clinical trial to test whether increasing the dose of radiotherapy can improve outcomes for patients with mesothelioma, which is an extremely difficult cancer to treat.

"We are very excited to see some early evidence that patients receiving the higher radiotherapy dose might benefit in terms of an increase in their life expectancy. We are still in the process of following up these patients and analysing the results, however, so this observation should be treated with caution at this stage."

Professor Corinne Faivre-Finn, Professor of Thoracic Radiation Oncology at the University of Manchester, added: "SYSTEMS-2 is an important patient-centred study addressing pain control, an area of unmet clinical need in the field of pleural mesothelioma.

"The survival results of SYSTEMS-2 are interesting but cannot be considered conclusive as data is not yet mature. A phase 3 study with overall survival as an endpoint is ideally required to confirm the impact of thoracic radiotherapy in patients with pleural mesothelioma."

BTOG’s Steering Committee Chair, Professor Sanjay Popat said: "The UK remains a world leader in the field of clinical research for mesothelioma. The SYSTEMS-2 trial is a highly anticipated, important trial for the global mesothelioma community and I am delighted that the trial data were first shared with the world at the BTOG 2023 Annual Conference. The UK continues to have one of the highest rates of mesothelioma in the world due to its previous legacy of asbestos use and research into mesothelioma treatments remain an ongoing priority."

The SYSTEMS-2 study was co-ordinated via the Cancer Research UK Clinical Trials Unit, Glasgow and sponsored by the Greater Glasgow Health Board and University of Glasgow. Funding the for study was provided by educational grants from The June Hancock Mesothelioma Research Fund and The Beatson Cancer Charity.