Increasing Radiation Therapy Dose Is Associated With Improved Survival in Patients Undergoing Stereotactic Body Radiation Therapy for Stage I Non–Small-Cell Lung Cancer

Journal Article · Sun Feb 01 04:00:00 EST 2015 · International Journal of Radiation Oncology, Biology and Physics

DOI:https://doi.org/10.1016/J.IJROBP.2014.10.002· OSTI ID:22458601

Koshy, Matthew ^[1]; Malik, Renuka ^[2]; Weichselbaum, Ralph R. ^[1]; Sher, David J. ^[3]

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1. Department of Radiation Oncology, University of Illinois at Chicago, Chicago, Illinois (United States)
2. Department of Radiation and Cellular Oncology, The University of Chicago, Chicago, Illinois (United States)
3. Department of Radiation Oncology, Rush University Medical Center, Chicago, Illinois (United States)

Purpose: To determine the comparative effectiveness of different stereotactic body radiation therapy (SBRT) dosing regimens for early-stage non–small-cell lung cancer, using a large national database, focusing on the relative impact of dose as a function of tumor stage. Methods and Materials: The study included patients in the National Cancer Database from 2003 to 2006 with T1-T2N0M0 inoperable lung cancer (n=498). The biologically effective dose (BED) was calculated according to the linear quadratic formula using an α/β ratio of 10. High versus lower-dose (HD vs LD) SBRT was defined as a calculated BED above or below 150 Gy. Overall survival was estimated using Kaplan-Meier methods and Cox proportional hazard regression. Results: The 5 most common dose fractionation schemes (percentage of cohort) used were 20 Gy × 3 (34%), 12 Gy × 4 (16%), 18 Gy × 3 (10%), 15 Gy × 3 (10%), and 16 Gy × 3 (4%). The median calculated BED was 150 Gy (interquartile range 106-166 Gy). The 3-year overall survival (OS) for patients who received HD versus LD was 55% versus 46% (log–rank P=.03). On subset analysis of the T1 cohort there was no association between calculated BED and 3-year OS (61% vs 60% with HD vs LD, P=.9). Among the T2 cohort, patients receiving HD experienced superior 3-year OS (37% vs 24%, P=.01). On multivariable analysis, factors independently prognostic for mortality were female gender (hazard ratio [HR] 0.76, P=.01), T2 tumor (HR 1.99, P=.0001), and HD (HR 0.68, P=.001). Conclusions: This comparative effectiveness analysis of SBRT dose for patients with stage I non–small-cell lung cancer suggests that higher doses (>150 Gy BED) are associated with a significant survival benefit in patients with T2 tumors.

• OSTI ID: 22458601
• Journal Information: International Journal of Radiation Oncology, Biology and Physics, Journal Name: International Journal of Radiation Oncology, Biology and Physics Journal Issue: 2 Vol. 91; ISSN IOBPD3; ISSN 0360-3016
• Country of Publication: United States
• Language: English

Related Subjects

62 RADIOLOGY AND NUCLEAR MEDICINE
AUGMENTATION
FEMALES
FOCUSING
FRACTIONATED IRRADIATION
HAZARDS
LUNGS
MORTALITY
NEOPLASMS
PATIENTS
RADIATION DOSES
RADIOTHERAPY