A population-based comparative effectiveness study of radiation therapy techniques in stage III non-small cell lung cancer.
OBJECTIVE
Concerns have been raised about the potential for worse treatment outcomes because of dosimetric inaccuracies related to tumor motion and increased toxicity caused by the spread of low-dose radiation to normal tissues in patients with locally advanced non-small cell lung cancer (NSCLC) treated with intensity modulated radiation therapy (IMRT). We therefore performed a population-based comparative effectiveness analysis of IMRT, conventional 3-dimensional conformal radiation therapy (3D-CRT), and 2-dimensional radiation therapy (2D-RT) in stage III NSCLC.


METHODS
We used the Surveillance, Epidemiology, and End Results (SEER)-Medicare database to identify a cohort of patients diagnosed with stage III NSCLC from 2002 to 2009 treated with IMRT, 3D-CRT, or 2D-RT. Using Cox regression and propensity score matching, we compared survival and toxicities of these treatments.


RESULTS
The proportion of patients treated with IMRT increased from 2% in 2002 to 25% in 2009, and the use of 2D-RT decreased from 32% to 3%. In univariate analysis, IMRT was associated with improved overall survival (OS) (hazard ratio [HR] 0.90, P=.02) and cancer-specific survival (CSS) (HR 0.89, P=.02). After controlling for confounders, IMRT was associated with similar OS (HR 0.94, P=.23) and CSS (HR 0.94, P=.28) compared with 3D-CRT. Both techniques had superior OS compared with 2D-RT. IMRT was associated with similar toxicity risks on multivariate analysis compared with 3D-CRT. Propensity score matched model results were similar to those from adjusted models.


CONCLUSIONS
In this population-based analysis, IMRT for stage III NSCLC was associated with similar OS and CSS and maintained similar toxicity risks compared with 3D-CRT.
Department of Radiation Oncology, Stanford University School of Medicine, Stanford, California.
Jeremy P
JP
Harris
Department of Radiation Medicine and Applied Science, University of California- San Diego, Moores Cancer Center, La Jolla, California.
James D
JD
Murphy
Department of Radiation Oncology, Stanford University School of Medicine, Stanford, California; University of Pennsylvania School of Nursing, Philadelphia, Pennsylvania.
Alexandra L
AL
Hanlon
Department of Radiation Oncology, Stanford University School of Medicine, Stanford, California; Stanford Cancer Institute, Stanford University School of Medicine, Stanford, California.
Quynh-Thu
QT
Le
Department of Radiation Oncology, Stanford University School of Medicine, Stanford, California; Stanford Cancer Institute, Stanford University School of Medicine, Stanford, California. Electronic address: BWLoo@Stanford.edu.
Billy W
BW
Loo
Department of Radiation Oncology, Stanford University School of Medicine, Stanford, California; Stanford Cancer Institute, Stanford University School of Medicine, Stanford, California; Institute for Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, Stanford, California. Electronic address: diehn@Stanford.edu.
Maximilian
M
Diehn
D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D016190:Carboplatin / Q000008:administration & dosage; D002289:Carcinoma, Non-Small-Cell Lung / Q000188:drug therapy / Q000401:mortality / Q000473:pathology / Q000532:radiotherapy*; D057186:Comparative Effectiveness Research; D005047:Etoposide / Q000008:administration & dosage; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000188:drug therapy / Q000401:mortality / Q000473:pathology / Q000532:radiotherapy*; D008297:Male; D011879:Radiotherapy Dosage; D020266:Radiotherapy, Conformal / Q000009:adverse effects / Q000401:mortality / Q000706:statistics & numerical data; D050397:Radiotherapy, Intensity-Modulated / Q000009:adverse effects / Q000401:mortality / Q000706:statistics & numerical data; D018426:SEER Program; D016896:Treatment Outcome
D005047:Etoposide; D016190:Carboplatin