ESTRO 2024 Congress report

In the largest, two-floor Clyde auditorium, presenters from the UK, USA, Belgium, The Netherlands, South Korea and Germany spoke to a packed room and enjoyed massive amounts of fruitful discussion.

The first study came from Anthony Chalmers, in which he shared promising data from the PARADIGM-2 trial on unmethylated glioblastoma (GBM). PARADIGM-2 is a Phase I study of the use of olaparib and radiotherapy in newly diagnosed GBM. Forty-two patients started olaparib three days before radiotherapy and continued until four weeks after. They were stratified according to levels of methylguanine-DNA-methyltransferase (MGMT). In the unmethylated cohort who had been treated with full doses of olaparib, the median overall survival (OS) rate was 14.2 months and the two-year OS rate was 24.7%. In contrast, the figure for the dose expansion cohorts was 16.7%. No dose-limiting toxicity was found. A development of a phase III trial of the use of radiotherapy plus Niraparib was announced. Now we are waiting for an update on the MGMT methylated cohort.

Impressive interim results were presented by Woo-Yoon Park on patients with Alzheimer’s disease who had been treated with low-dose radiotherapy (LDRT). The report was of a multicentre, randomised, single-blind, phase II clinical trial. LDRT may modulate microglia phenotype in creating resilience in the intracranial environment. The presented data indicated that the use of LDRT inhibited atrophy of the hippocampus, as measured through the use of volumetric MRI, and resulted in improved conditions of the patients after 12 months, in comparison with controls.

Single-fraction stereotactic radiosurgery (SRS) is a well-established way to manage small brain metastases. However, local failure (LF) and radiation necrosis (RN) pose challenges. Sreenija Yarlagadda identified predictors of LF, RN and time to onset of symptoms, which may help us to personalise treatment.

Structural network hubs as potential organs-at-risk in glioma patients after radiotherapy were presented by Laurien de Roeck from Leuven. Cognitive impairment was found in 60% of glioma survivors, especially among those who had left-sided tumours. Associations between pre- and post-central, and superior frontal, gyrus were much higher than those between hippocampal dose and verbal memory. Fariba Tohidinezhad from Maastricht University analysed the impacts of dosimetric and clinical factors on cognitive deterioration 6, 12 and 24 months after treatment and reported some interesting correlations, e.g. with cerebellar dose.

The highlight for me was data presented by Maximilian Grohmann from University Medical Center Hamburg-Eppendorf, Germany, regarding results that are emerging after retreatment with SRS. It was very informative to see that even multiple series of SRS may offer benefits to patients and prolong their survival.

During ESTRO 24, the central nervous system (CNS) was covered in a single proffered paper session, and interest was so strong that perhaps this would lead to a stronger CNS programme next year.

Maciej Harat - radiation oncologist

Department of Neurooncology and Radiosurgery 

Franciszek Lukaszczyk Oncology Center (FLOC)

University of Science and Technology, Bydgoszcz Poland

ESTRO CNS focus group