39 - Freie Mitteilung
Clinical works I
16. Mai 2019, 08:30 - 10:00, Bellavista 2, 6. OG
Stage IIIA should be divided in two different subgroups according to n and t stage in patients with resected lung cancer: Validation with another center database
N. Citak1, 2, L. Guglielmetti1, Y. Aksoy2, O. Isgörücü2, M. Metin2, A. Sayar2, I. Opitz1, D. Schneiter1, W. Weder1, I. Inci1, Presenter: N. Citak1, 2 (1Zürich, 2Istanbul/TR)
Stage IIIA-NSCLC includes a very heterogeneous group of patients depending on tumor localization, and extension of nodal disease. Therefore therapy still remains very controversial. The purpose of our study was to compare the survival between Stage IIIA subsets (T3N1 or T4N0/1 versus T1/2N2), and to validate our results with another center database.
Between 2007 and 2017, 2057 patients completely resected for NSCLC were retrospectively analyzed. There were 424 patients who had Stage IIIA and 82 patients who had Stage IIIB (T3/4N2). Stage IIIA patients were divided into two subsets according to tumor localization (T3N1 and T4N0/1, IIIA-T group; n=308) and extension of nodal disease (T1/2N2, IIIA-N2 group; n=116). Age, gender, pack/years, and comorbidity did not differ between subsets. Another Thoracic Surgery Center cancer database was used for validation.
IIIA-N2 group had more adenocarcinoma than IIIA-T group (52.6% vs 29.5%, p<0.001), and pneumonectomy was more performed in IIIA-T group (51.0% vs 32.8%, p=0.001). In multivariate analysis, N2 and age > 65 were significant independent negative prognostic factors (p<0.001). Five-year survival for patients in IIIA-T group was 51.3% (median 64 months), whereas it was 25.7% (median 31 months) for IIIA-N2 patients (HR: 1.834, 95%CI [1.345-2.501], p<0.0001) (Figure 1). There was no statistically difference regarding the survival between IIIA-N2 and Stage IIIB (25.7% vs 25.3%, p=0.4). According to the results, we performed a re-staging for Validation Cohort patients as; Stage IIIA-T (including T3N1 and T4N0/1) (n=139), Stage IIIA-N (including T1/2N2) (n=104), and Stage IIIB (n=50). Stage IIIA-T had a statistically better survival than Stage IIIA-N (50.5% vs 27.1%, HR: 1.707, 95%CI [1.231-2.366], p=0.0007), whereas five-year survival rates were similar for Stage IIIA-N and Stage IIIB (27.1% vs 27.1%, p=0.9) (Figure 2).
Since our results were validated with another center database, we propose that stage IIIA should be divided into two different subgroups according to the primary tumor extension (T) and mediastinal lymph node involvement (N) in the next TNM classification.