Prognostic heterogeneity in multilevel N2 non-small cell lung cancer patients: importance of lymphadenopathy and occult intrapulmonary metastases

Abstract

Background: To evaluate prognostic heterogeneity that may exist in multilevel N2 non-small lung cancer, we attempted to identify clinicopathologic prognostic factors for multilevel N2 patients who underwent standard surgeries.

Methods: We retrospectively evaluated records from 1988 to December 2007 for 106 non-small lung cancer patients diagnosed with multilevel N2 disease by postoperative pathologic examination (49 women, 57 men; median age=61 years). Patients with clinical T4 (cT4) and bulky N2 (shortest mediastinal lymph node diameter>2 cm) disease were excluded from the study. Follow-up periods ranged from 2 to 240 months (median for living patients=36 months). Records were examined for age, sex, preoperative nodal status (cN2 versus cN0 or cN1), primary tumor sites, surgical procedure, metastatic stations (distribution and numbers), tumor sizes, histologic features, and adjuvant therapies.

Results: By univariate analysis, cN (cN2), intrapulmonary metastases within the same lobe of the primary tumor (PM), and male sex were significant adverse prognostic factors; smoking only tended toward significance (p=0.1). Other clinicopathologic variables were not significant prognostic factors. By multivariate analysis, cN (cN2) and PM were significant prognostic factors. Patients who had neither cN2 nor PM had significantly higher survival rates than those who had either cN2 or PM (5-year survival rates of 36.5% and 11.2%, respectively).

Conclusions: Multilevel N2 patients can be grouped according to the prognostic factors cN2 and PM. These findings have potential for evaluating the best therapeutic modalities or agents for multilevel N2 patients.