Retrospective study of patients with pathologic N1-stage II non-small cell lung cancer

Department of Thoracic Surgery, Kurashiki Central Hospital, 1-1-1 Miwa, Kurashiki, Okayama, 710-8602, Japan *Corresponding author. Tel.: +81-86-422-0210; fax: +81-86-421-3424. E-mail address : tn8336{at}kchnet.or.jp (T. Nakagawa). The population of patients with N1-stage II disease is small among non-small cell lung cancer patients and there have been relatively few studies regarding prognostic factors for the disease. We retrospectively evaluated the clinicopathological features of the disease to identify prognostic factors. The clinical records of 85 patients with N1-stage II non-small cell lung cancer who underwent lobectomy or pneumonectomy with systematic lymph node dissection or sampling were retrospectively reviewed. The study population comprised 64 men and 21 women, among whom 49 had adenocarcinoma, six had squamous cell carcinoma and two had large cell carcinoma. The prognosis was significantly better for p0 vs. p2–3 disease ( P =0.029), pneumonectomy vs. lobectomy ( P =0.027) and direct extension vs. metastasis to N1 lymph nodes ( P =0.015). On the other hand, there was no significant difference in survival regarding the number or level of the involved lymph node stations. A multivariate analysis for prognostic factors revealed that status of lymph node involvement as well as gender and pleural factor was a significant independent prognostic factor ( P =0.026). Our results have revealed that direct extension to N1 lymph nodes is an independent favorable prognostic factor as opposed to metastasis for surgically-treated patients with N1-stage II disease. Key Words: Lung cancer; Lymph nodes; Statistics; Survival analysis