Is the prognosis of occult N2 disease similar to that of positive positron emission tomography-computed tomography (PET/CT) scan single-station N2 disease in patients with non-small cell lung cancer treated by surgical resection?

Abstract

ObjectiveA retrospective study, using a prospective database, was conducted on patients treated with surgery in order to analyze the prognosis between two groups: NSCLC (non-small cell lung cancer) patients with occult N2 disease and patients with single station N2 disease observed on pre-operative integrated PET/CT scan. MethodsA total of 772 patients underwent surgical treatment for lung cancer from January 2007 to December 2014. All of them had an integrated PET/CT scan in the pre-operative work-up and a pulmonary resection plus mediastinal lymphadenectomy were performed in all cases. In the selected cases, no one received induction treatment. All patients from both groups had N2 disease after examination of the histopathology specimen. Clinical and pathological characteristics, disease free survival, and overall survival, were analyzed in both groups. ResultsA total of 34 cases presented occult N2 disease, whereas 11 cases showed single station N2 disease on pre-operative PET/CT scan. Mean disease free survival and mean overall survival for occult N2 disease compared to single-station N2 disease on PET/CT scan was 36.0 months (95% CI: 24.9–47.1) and 38.9 months (95% CI: 20.6–57.1), p=.586; and 52.3 months (95% CI: 38.9–65.7) and 38.2 months (95% CI: 21.9–54.5), p=.349, respectively. ConclusionThe prognosis of patients with single-station N2 disease on PET/CT scan treated by surgical resection and mediastinal lymphadenectomy as first line treatment was similar to those with occult N2 disease. More studies are needed to support our findings.