Prognostic factors in resected satellite-nodule T4 non-small cell lung cancer

Background. The 1997 non-small cell lung cancer staging revisions assigned a T4 descriptor to satellite nodules in the primary tumor lobe. We reviewed our experience of satellite-nodule T4 non-small cell lung cancer following these revisions and evaluated prognostic factors for this group. Methods. All patients who underwent resection of non-small cell lung cancer between April 1997 and June 2005 with satellite nodule(s) confirmed at pathologic examination were identified from our institutional Lung Tumor Registry. Case notes and pathology reports were reviewed and data collected on possible prognostic factors. Survival was modeled using the Kaplan-Meier method, and survival differences between groups were analyzed using the log-rank test. Results. From 1,276 non-small cell lung cancer patients who underwent resection, 137 were staged pT4, and 35 were T4-satellite nodules. Median follow-up was 25 months ( range, 1 to 102 months). Median main tumor size was 3.0 cm ( range, 1 to 9.8 cm). Adenocarcinoma or bronchioloalveolar carcinoma was the predominant histologic diagnosis (n = 28; 80%). One-, 3- and 5-year survival was 86%, 69%, and 57%, respectively; median survival was 68 months. During the same period, 137 patients undergoing resection for all T4 lesions had a 1-, 3-, and 5-year survival of 68%, 53%, and 18%, respectively. Adenocarcinoma or bronchioloalveolar carcinoma histologic diagnosis ( adenocarcinoma or bronchioloalveolar carcinoma versus squamous, 75% versus 67% 3- year survival; p = 0.0026), female gender (66% versus 49% for males, 5-year survival; p = 0.041), and absence of vascular invasion ( no invasion versus vascular invasion, 74% versus 20% 5-year survival; p = 0.0101) were significant predictors of better survival. Conclusions. Survival for resected T4 non-small cell lung cancer with satellite nodule(s) in the primary lobe is better than for other T4 lesions, and the T4 descriptor may unduly upstage these cases. The current T4 descriptor represents a heterogeneous population.