IMPT Dose Escalation for NSCLC (HyDose)

Radiotherapy Dose Escalation Using Intensity-modulated Proton Therapy for Non-small-cell Lung Cancer Patients

The goal of this clinical pilot trial is to learn if dose to the tumor in the lung can be safely increased using proton therapy in stage III non-small-cell lung cancer patients receiving combined chemotherapy and radiotherapy. The main questions it aims to answer are:

• Is the risk of severe radiotherapy toxicities (requiring hospital admission) within acceptable margins ?
• What is a rough estimate of the effect of the treatment under study?

Compared to standard care in our clinic, all participants in this pilot trial will

• Receive a higher dose of proton therapy to the tumor in the lung albeit with the same number of radiotherapy visits as the current standard treatment.
• Receive two additional follow-up visits at the clinic after treatment, namely 4 and 6 weeks after finishing radiotherapy.
• Two additional blood withdrawals at the last week of radiotherapy and 4 weeks after finishing radiotherapy, to measure a type of white blood cells.
• Receive an extra quality of life questionnaire at the last week of radiotherapy.

Inclusion Criteria:

• Age ≥18 years
• WHO performance score 0-2
• Histologically proven stage III NSCLC
• Planned for CCRT and adjuvant immunotherapy (intention to treat)
• Primary tumour volume outside of mediastinal PRV (i.e., mediastinal envelope + 5 mm) ≥60% of total primary tumour volume (true for 75% of patients in preliminary analysis), for sufficient dose escalation

Exclusion Criteria:

• Chemotherapy not given concurrently with radiotherapy
• Upfront decision that adjuvant immunotherapy is not possible
• Primary tumour overlapping ≥40% with mediastinal PRV
• Unable or unwilling to understand the information on trial-related topics, to give informed consent or to fill out quality-of-life questionnaires