Clinical outcome of image-guided adaptive radiotherapy in the treatment of lung cancer patients

• Published in: Acta oncologica Vol. 54; no. 9; p. 1430
• Main Authors: Tvilum, Marie, Khalil, Azza A, Møller, Ditte S, Hoffmann, Lone, Knap, Marianne M
• Format: Journal Article
• Language: English
• Published: England 21-10-2015
• Subjects: Adult; Aged; Aged, 80 and over; Carcinoma - diagnostic imaging; Carcinoma - radiotherapy; Case-Control Studies; Denmark - epidemiology; Female; Follow-Up Studies; Humans; Lung Neoplasms - diagnostic imaging; Lung Neoplasms - radiotherapy; Male; Middle Aged; Multidetector Computed Tomography; Neoplasm Recurrence, Local - diagnostic imaging; Radiation Pneumonitis - epidemiology; Radiotherapy, Image-Guided; Radiotherapy, Intensity-Modulated
• ISSN: 1651-226X
• DOI: 10.3109/0284186X.2015.1062544

Adaptive strategy with daily online tumour match is a treatment option when treating locally advanced lung cancer patients with curative intended radiotherapy (RT).
Fifty-two consecutive lung cancer patients treated with soft tissue match, adaptive RT and small planning target volumes (PTV) margins were analysed. A control group of 52 consecutive patients treated with bone match, no adaptive strategy and larger margins was included. Patients were followed with computed tomography (CT) scans every third month. CT-images showing loco-regional recurrences were identified. The recurrence gross tumour volume was delineated and registered with the original radiation treatment plan to identify site of failure. All patients were toxicity-scored using CTCAE 4.03 grading scale. Data were analysed using the Kaplan-Meier analysis.
The median follow-up time was 16 months (3-35). Within a year, 35% of the patients in the adaptive group (ART-group) and 53% in the control group (No-ART-group) experienced loco-regional failure, showing improved loco-regional control in the ART group (p = 0.05). One patient in the ART-group and four patients in the No-ART-group showed marginal failure. Median overall progression-free survival time for the ART-group was 10 months (95% CI 8-12), and 8 months (95% CI 6-9) for the No-ART-group. Severe pneumonitis (grade 3-5) decreased from 22% in the No-ART-group to 18% in the ART-group (non-significant, p = 0.6). No significant difference in severe dysphagia was found between the two groups.
In the first small cohort of patients investigated, implementation of soft-tissue tumour match and adaptive strategies for locally advanced lung cancer patients increased the loco-regional control rate without increasing treatment-related toxicity.