SEATTLE — Patients with positive surgical margins after lobectomy and adjuvant radiation for non-small cell lung cancer had an increased risk for death compared with patients who were treated with pneumonectomy without radiation.
“We have demonstrated that positive margins are not that uncommon and occur in roughly 4% of patients receiving lobectomy for stage I or II non-small cell lung cancer [NSCLC],” Brian C. Gulack, MD, of Duke University, said during a presentation at the American Association for Thoracic Surgery Annual Meeting. “Furthermore, positive margin status is associated with worse overall survival, and among patients with positive margins, adjuvant radiation therapy does not appear to provide a significant long-term survival benefit.”
Brian C. Gulack
Gulack and colleagues analyzed patients with positive margins after lobectomy for stage I and stage II NSCLC from the National Cancer Data Base to determine if adjuvant radiation improved survival. Patients who underwent lobectomy without known induction therapy for NSCLC from 1998 to 2006 were grouped by margin status and assessed based on treatment and outcomes.
Among 50,010 patients who met study criteria, 3.9% had positive margins after lobectomy. Positive margins were associated with an increased risk for death (adjusted HR = 1.46; 95% CI, 1.39-1.6).
Of patients with positive margins (n = 1,598) and stage I or stage II cancer, adjuvant radiation was used in 38.2 % of cases, which Gulack said did not significantly impact survival (aHR = 1.08; 95% CI, 0.88-1.32).
Patients who underwent pneumonectomy without adjuvant radiation, however, had improved survival after a 5-year period when compared with patients who had lobectomy and subsequent adjuvant radiation (HR = 0.5; 95% CI, 0.38-0.66).
Gulack acknowledged there were limitations with the study.
“We did not have access to treatment decision details such as why or why not the patient may have received adjuvant radiation therapy or why or why not the patient may have undergone re-resection,” he said.
“Second, although we could determine which patients received adjuvant radiation therapy, we cannot necessarily determine the reason why because it’s possible some patients who received adjuvant radiation therapy did so for other reasons than positive margin status.”
Gulack said the findings support the occasional use of re-resection.
“Our findings also suggest that re-resection, when feasible, may be a superior treatment option to adjuvant radiation therapy.” – by Ryan McDonald
Gulack BC, et al. Plenary 48. Presented at: the American Association for Thoracic Surgery Annual Meeting; April 25-29, 2015; Seattle.
Disclosure: Gulack reports no relevant financial disclosures.