Chemotherapy followed by radiation resulted in superior outcomes compared with concurrent chemoradiotherapy in patients with non–small-cell lung cancer (NSCLC) who had negative margins after surgery and pN2 disease, according to results of a retrospective analysis.
“We also found that sequential therapy is becoming the more frequent practice pattern over time for patients with R0 pN2 disease, and our results support this practice,” wrote Samual Francis, MD, of the University of Utah Huntsman Cancer Institute, Salt Lake City, and his coauthors.
By contrast, there was no clear association between treatment sequence and survival among patients who had positive margins after surgery in this analysis, authors of the study reported (J Clin Oncol. 2017 Dec 13. doi: 10.1200/JCO.2017.74.4771).
The study included 1,024 patients in National Cancer Database who received a diagnosis of nonmetastatic NSCLC and received chemotherapy and radiation concurrently or sequentially after surgery. Of those patients, 747 had R0 resections and pN2 nodal status, and the remainder had R1 or R2 resections and pN0-N2 disease.
For patients with R0 pN2 NSCLC, median overall survival was 58.8 months for sequential chemotherapy followed by radiation, versus 40.4 months for concurrent chemoradiotherapy (log-rank P less than .001), data show.
That association between sequential treatment and improved overall survival remained significant even after propensity score matching (hazard ratio [HR], 1.35; P = .019), investigators reported.
However, for the remaining cohort of patients with positive margins regardless of nodal status, there was no significant difference in overall survival favoring either approach (42.6 months for sequential versus 38.5 months for concurrent; log-rank P = .42), they added, and no clear association between treatment approaches (HR 1.35; P = .19).
The analysis covered patients diagnosed between 2006 and 2012, the most recent data period available.
Investigators were also able to identify changes in practice patterns over time using this data set. Between 2006 and 2012, there was an increase in the use of sequential chemotherapy and radiotherapy for patients with R0 resection and pN2 disease, and a decrease in the use of concurrent chemoradiotherapy.
Conversely, they found that for patients with positive margins, there was an increase over time in use of the concurrent approach and decrease in the sequential approach.
“These findings suggest practice patterns have shifted toward concordance with consensus guideline recommendations over time,” Dr. Francis and his colleagues said in their report.
Current guidelines advocate for chemotherapy followed by postoperative radiotherapy for patients with negative margins and pN2 disease, but suggest concurrent chemoradiotherapy for patients with positive margins, they added.
Dr. Francis had no relationships to disclose. Study coauthors reported disclosures related to Elekta, ProLung, Merit Medical Systems, and Bard Medical.