Adaptive proton therapy in lung cancer

Principal Investigator:  Liv Bolstad Hysing

Team/collaborators: Mari Hjelstuen, Kjell Ivar Dybvig, Lukas Hirschi, Helga Gripsgård, Terje Nordberg

Background

Lung cancer is the deadliest cancer worldwide, and radiotherapy is an important treatment modality for patients with inoperable cancer that are treated in a curative setting. Better local control is a key to improving survival in patients with locally advanced non-small cell lung cancer. Proton therapy has the potential to increase doses to the tumour while sparing surrounding healthy tissue and we are therefore planning a randomized phase I/II dose-escalation trial with proton therapy to increase response to treatment, given that the toxicity is acceptable. As very few studies have been performed with proton therapy to such high doses, we will initially investigate the feasibility and tolerance of the suggested treatment. Proton therapy is technically challenging for these patients with a risk of missing the tumour unless anatomical changes like atelectasis, pleural effusion, changes in breathing motion pattern or breath hold, and tumour growth or shrinkage are appropriately accounted for through adaptive radiotherapy.

Goal

Develop and prospectively evaluate an adaptive protocol for proton therapy for lung cancer

Approach

• Develop an adaptive protocol for proton therapy in lung cancer using retrospective data from standard treatment
• Prospectively evaluate the protocol in a national clinical trial
• Explore strategies for intra-fractional motion mitigation

Impact

Adaptation is crucial for the safety and feasibility of using proton therapy for dose-escalation in lung cancer. If this novel treatment strategy is feasible, we can improve local control and thus survival for patients with locally advanced lung cancer. Furthermore, this is an important step towards expanding indications suitable for proton treatment.