ONLINE adaptive radiotherapy (oART) represents a cutting-edge approach to cancer treatment, using daily imaging to account for changes in a patient’s anatomy. This method generates a personalised treatment plan for each session, making it particularly beneficial for treating gastric mucosa-associated lymphoid tissue (MALT) lymphomas, which account for 4% of all non-Hodgkin lymphomas and are typically linked to Helicobacter pylori infection. when antibiotic treatment fails radiotherapy emerges as an option.
The study, led by Cliniques universitaires Saint-Luc, Belgium, aimed to determine the movement occurring during a single treatment session, intrafraction motion, and the planning target volume (PTV) margins needed for oART using a cone beam computed tomography (CBCT)-based system. It compared this adaptive method to a non-adaptive approach for three patients undergoing breath-hold (BH) radiotherapy for gastric MALT lymphoma.
Using CBCT imaging before and after each treatment session, PTV margins for both adaptive and non-adaptive workflows were calculated. The adaptive approach required a smaller PTV margin of 4mm compared to 12mm for non-adaptive treatment, representing a significant reduction in the treated area. This margin reduction limits unnecessary radiation to surrounding healthy tissues, lowering the risk of treatment-related side effects.
The dosimetric analysis revealed that both approaches met clinical dose constraints, but the adaptive plans resulted in lower radiation doses to organs-at-risk (OARs). The findings suggest that oART can effectively minimise treatment areas while maintaining target coverage, offering a safer and potentially more effective treatment for gastric MALT lymphomas.
The researchers concluded that oART, with BH technique, shows promise in reducing PTV margins and OAR doses in gastric lymphoma patients, however, more extensive studies are needed to confirm these results and evaluate their long-term clinical impact.
Katie Wright, EMJ
Reference
Tison T et al. Online adaptive radiotherapy for planning target volume (PTV) reduction in gastric mucosa-associated lymphoid tissue (MALT) lymphoma. Cureus. 2024;16(9):e68919.
