Open AccessInterfraction movement and clinical outcome of immobilization for thoracic irradiation: A randomized controlled trial
Author(s) -
Pulvirenti Trish,
Agustin Cherry,
Tamas Monica,
Harris Jillian,
Verning Maria,
Cross Shamira,
Jayamohan Jayasingham,
YeghiaianAlvandi Roland,
Gebski Val
Publication year - 2018
Publication title -
precision radiation oncology
Language(s) - English
Resource type - Journals
ISSN - 2398-7324
DOI - 10.1002/pro6.35
Subject(s) - isocenter , medicine , randomized controlled trial , thorax (insect anatomy) , radiation therapy , esophagus , surgery , nuclear medicine , clinical endpoint , anatomy
Objective To evaluate the impact of immobilization on set‐up errors and clinical outcomes in patients receiving radiation therapy to the thorax. Methods Patients receiving curative intent radiation therapy to the lung and esophagus were randomized to no immobilization (control) or immobilization (chest jig or vacuum bag), and treatment verification images were acquired within 3 days of commencing treatment and then weekly. The primary outcome was the proportion of patients having a deviation >5 mm from the isocenter. Assessment was carried out blinded to immobilization assignment. Results Of the 77 patients, 75 patients were allocated to either immobilization or control. No statistical difference in the proportion of patients with bony displacements >5 mm from the isocenter were observed ( P = 0.5), as was the case for both systematic and random errors between the groups. There was an increased risk of local failure in the immobilized control group (HR 1.46, 95% CI 0.78–2.71, P = 0.23) based on a competing risk analysis. The median overall survival was 18.4 months and 27.0 months in the control and immobilized groups, respectively (HR 0.73, 95% CI 0.51–1.04, P = 0.08). Conclusions The results failed to show benefit with immobilization in reducing set‐up errors, local control, and overall survival.