Non-small cell lung cancer (NSCLC) is by far the commonest form of lung cancer, with about 80% of patients found to have this type of the disease. Localised disease, diagnosed before it has spread, is generally treated with surgery.

The lungs are divided into five lobes, three on the right and two on the left, each surrounded by a pleural membrane; the standard surgical treatment for NSCLC is lobectomy, defined as the removal of one lobe and its associated lymph nodes.

However, limited or sub-lobal resections, in which a section of lung tissue smaller than a single lobe is removed, are becoming more popular. As these remove less tissue they are thought to be of particular benefit to patients with poor lung function, but there is conversely a theoretically higher risk of local recurrence.

Sarah Billmeier and her colleagues at the Center for Surgery and Public Health, Brigham and Women's Hospital, Boston, Massachusetts, USA have now used a population-based observation study to compare the predictors and outcomes of limited resection with those of lobectomy in early-stage NSCLC.

The study included a total of 679 patients newly diagnosed with Stage I or II NSCLC in a number of different healthcare regions within the US; 155 (23%) of these patients underwent limited resection and 524 (77%) lobectomy. Data was obtained from medical records and from telephone interviews with the patients or their surrogates, and the surgeons involved were also surveyed.

Most of the patients in the study were male, white and over 65, and 85% were current or former smokers. Patients in the limited resection group were more seriously ill with lung disease and were more likely to have a history of heart disease or stroke, but had smaller tumours with more diagnosed as Stage I NSCLC. Interestingly, patients with Medicare, Medicaid or no health insurance were more likely to receive limited resection than those with private insurance.

However, the only clinical variables that remained statistically significant as predictors of limited resection in a multivariate model were small tumour size, more severe lung disease and a history of stroke. Surgeons specialising in thoracic surgery and working in National Cancer Institute designated cancer centres were more likely to perform limited resection, and those paid on a fee-for-service basis were more likely to perform lobectomy.

Both 30-day and long term mortality, the latter measured with a median follow-up time of 55 months, were slightly higher in patients undergoing limited resection than in those undergoing lobectomy. However, these differences were not statistically significant after adjustment for demographic and other health characteristics. There was also no significant difference between the treatment modalities in the rate of post-operative complications.

Billmeier and her colleagues conclude that the proportion of patients in the survey who underwent limited resection for early-stage NSCLC was relatively high given that lobectomy is considered the standard treatment. Furthermore, their results suggest inconclusively that lobectomy may have better outcomes in many cases.

There is undoubtedly a place for limited resection in the treatment of patients with small tumours, but treatment decisions should be based on the clinical features of the case rather than socio-economic ones such as the patient's insurance status.

Reference

Billmeier, S.E., Ayanian, J.Z., Zaslavsky, A.M., Nerenz, D.R. Jaklitsch, M.T., and Rogers, S.O. (2011). Predictors and Outcomes of Limited Resection for Early-Stage Non–Small Cell Lung Cancer. J Natl Cancer Inst 103, 1–9. doi: 10.1093/jnci/djr387