15 mm margins cut NSCLC local recurrence risk after wedge resection
medwireNews: Increasing margin distance up to 15 mm significantly decreases the risk of local recurrence among patients undergoing wedge resection for early-stage, non-small-cell lung cancer (NSCLC), US researchers report.
Increasing the distance beyond 15 mm, however, provides no additional benefit, write Scott Swanson (Brigham and Women’s Hospital, Boston, Massachusetts) and colleagues in the Journal of Thoracic and Cardiovascular Surgery.
They say that their findings suggest that the risk of local recurrence during wedge resection for small (≤2 cm) NSCLC can be decreased if an adequate margin distance is achieved, but warn that the ideal margin distance for small tumours is still unclear.
The researchers reviewed the medical records of 479 patients who underwent wedge resection for small NSCLC between January 2001 and August 2011 with follow-up until December 2011.
During this time, the rates of local recurrence – defined as a tumour of the same histological type occurring within the same lobe, a tumour of the same histological type occurring in a different lobe or lung with carcinoma in the lymphatics common to both and/or extrapulmonary metastases – were 5.7%, 11.4% and 16.4% at 1, 2 and 3 years, respectively.
Over a third (35.3%) of patients had a margin distance of 1 to 5 mm, a quarter (25.7%) had a distance of 6 to 10 mm, 28.8% had a distance of 11 to 20 mm and 10.2% had a distance greater than 20 mm.
After adjustment for potential confounders, patients with a margin distance of 2 mm were found to have a 54% increased risk of local recurrence compared with patients with a margin distance of 5 mm.
Conversely, the local recurrence risk was 45% and 59% lower for patients with 10 mm and 15 mm margins, respectively, compared with those with 5 mm margins. Interestingly, having a margin distance of 20 mm provided no additional benefit over a 15 mm margin; patients with a 20 mm margin had a 54% lower risk of local recurrence than those with a 5 mm margin.
Swanson and co-authors note that they were unable to report on the effect margin distance might have on tumours of different sizes because the study did not have enough power to detect such an effect.
They conclude: “Our results suggest that an important avenue for future work will be to gather more data from patients from other institutes and to further determine the optimal margin distance for small tumors.”
medwireNews (www.medwirenews.com) is an independent clinical news service provided by Springer Healthcare Limited. © Springer Healthcare Ltd; 2014
By Laura Cowen, medwireNews Reporter