Results from a clinical trial evaluating the efficacy of real-time body surface visual feedback in reducing patient motion during lung cancer radiotherapy.

INTRODUCTION: Optical surface measurement devices are a maturing technology in radiotherapy. The challenge for such devices is to demonstrate how they can improve clinical care. We present results from a phase 1 clinical trial designed to test the hypothesis that if presented with live data from a novel optical measurement device, showing their deviation from an ideal radiotherapy treatment position, patients will be able to better control their motion and increase their geometrical conformance. METHOD AND MATERIALS: Fourteen lung cancer patients were enrolled in a prospective clinical study and asked to use a variety of visual feedback schema from a novel in-house developed optical surface measurement device. The magnitude and regularity of their body surface motion using the different schema was compared to that when free-breathing at three time-points throughout their radiotherapy treatment schedule. Additionally, 4D Cone Beam CT data, acquired simultaneously with the optical measurements, was used to test if improvements in external motion are reflected in changes in internal tumor motion. RESULTS: The primary endpoint of the trial, device tolerability assessed by the fraction of participants completing all study sessions, was 86%. Secondary endpoints showed that use of the visual feedback device was found to statistically significantly decrease body surface motion magnitude by an average of 17% over the study cohort, although not universally. Similarly body surface motion variability was decreased by 18% on average. Internal tumor motion magnitude was also found to be statistically significantly decreased by an average of 14% when using the feedback device. Reduction in external motion was predictive of reduced internal motion but no evidence of a simple correlation between changes in internal and external motion magnitude was found. CONCLUSIONS: Visual feedback of live motion is well tolerated by lung cancer patients and can reduce both body surface and tumor motion.

Protocol for the CONVERT trial-Concurrent ONce-daily VErsus twice-daily RadioTherapy: an international 2-arm randomised controlled trial of concurrent chemoradiotherapy comparing twice-daily and once-daily radiotherapy schedules in patients with limited stage small cell lung cancer (LS-SCLC) and good performance status.

INTRODUCTION: Concurrent ONce-daily VErsus twice-daily RadioTherapy (CONVERT) is the only multicentre, international, randomised, phase III trial open in Europe and Canada looking at optimisation of chemoradiotherapy (RT) in limited stage small cell lung cancer (LS-SCLC). Following on from the Turrisi trial of once-daily versus twice-daily (BD) concurrent chemoradiotherapy, there is a real need for a new phase III trial using modern conformal RT techniques and investigating higher once-daily radiation dose. This trial has the potential to define a new standard chemo-RT regimen for patients with LS-SCLC and good performance status. METHODS AND ANALYSIS: 447 patients with histologically or cytologically proven diagnosis of SCLC were recruited from 74 centres in eight countries between 2008 and 2013. Patients were randomised to receive either concurrent twice-daily RT(45 Gy in 30 twice-daily fractions over 3 weeks) or concurrent once-daily RT(66 Gy in 33 once-daily fractions over 6.5 weeks) both starting on day 22 of cycle 1. Patients are followed up until death. The primary end point of the study is overall survival and secondary end points include local progression-free survival, metastasis-free survival, acute and late toxicity based on the Common Terminology Criteria for Adverse Events V.3.0, chemotherapy and RTdose intensity. ETHICS AND DISSEMINATION: The trial received ethical approval from NRES Committee North West-Greater Manchester Central (07/H1008/229). There is a trial steering committee, including independent members and an independent data monitoring committee. Results will be published in a peer-reviewed journal and presented at international conferences. TRIAL REGISTRATION NUMBER: ISRCTN91927162; Pre-results.