Abstract

Introduction
Over the past 30 years, management of advanced lung cancer has changed profoundly, leading to variation in strategies for the use and timing of radiotherapy. Palliative radiotherapy is commonly offered to patients with stage IV non-small cell lung cancer (NSCLC). Dose fractionation trials from the 1990s demonstrated effectiveness in symptom control and suggested benefits in local disease management and survival among patients with good performance status. Current practice, however, continues to rely on dated evidence, and no recent trials have assessed radiotherapy in combination with contemporary systemic treatments.

Aims
PRINCE is a candidate-specific trial within the TOURIST platform. It aims to determine whether the addition of early highdose palliative thoracic radiotherapy to patients receiving first-line systemic treatment improves quality of life (QoL), overall survival (OS), progression-free survival (PFS), lung cancer symptoms, and toxicity.

Methods
Participants are randomised (1:1) to the control arm or to early high-dose palliative thoracic radiotherapy, with both groups receiving systemic therapy. Economic and process evaluations will also be undertaken, involving interviews with patients, carers, and healthcare professionals, alongside patient diaries.

Trial Progress We have 29 sites open to recruitment across England, Wales, Scotland and Northern Ireland, with the Republic of Ireland currently in set-up. Sites may open under the standard noncommercial agreement (mNCA) or a Hub and Spoke agreement. Patient Identification Centres are being introduced to support recruitment. 64 patients have been recruited to date. PRINCE is strongly represented with Patient and Public Involvement and Engagement (PPIE), which has been integral to the design of the trial, ensuring relevance to patient experience. The 12 month NIHR internal pilot has been completed, and recruitment will continue until 31 January 2028.

Disclosure
No significant relationship.