Marco Chiappetta1,2, Filippo Lococo1,2, Giovanni Leuzzi3, Isabella Sperduti4, Leonardo Petracca-Ciavarella1,2, Emilio Bria1,5, Felice Mucilli6, Pier Luigi Filosso7, Giovanni Battista Ratto8, Lorenzo Spaggiari9, Francesco Facciolo10, Stefano Margaritora1,2. 1. Università Cattolica del Sacro Cuore, Rome, Italy. 2. Thoracic Surgery, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy. 3. Thoracic Surgery Unit, Fondazione IRCCS Istituto Nazionale dei Tumori, Milan, Italy. 4. Biostatistics, Regina Elena National Cancer Institute, Rome, Italy. 5. Medical Oncology, Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, Italy. 6. Department of General and Thoracic Surgery, University Hospital "SS. Annunziata", Chieti, Italy. 7. Department of Thoracic Surgery, University of Turin, San Giovanni Battista Hospital, Turin, Italy. 8. Division of Thoracic Surgery, IRCCS AOU "San Martino" IST, Genoa, Italy. 9. Thoracic Surgery Division, European Institute of Oncology, University of Milan, Milan, Italy. 10. Thoracic Surgery, Regina Elena National Cancer Institute, Rome, Italy.
Abstract
OBJECTIVES: Overlapping survival curves for N1b (multiple N1 stations), N2a2 (single N2 station + N1 involvement) and N2a1 (skip N2 metastasis) limit the current tumour-node-metastasis (TNM) node (N) subclassification for node involvement. We validated externally the proposed subclassification. METHODS: Clinical records from a multicentric database comprising 1036 patients with pulmonary adenocarcinoma (ADC) or squamous cell carcinoma with N1/N2 involvement who underwent, from January 2002 to December 2014, complete lung resections were retrospectively reviewed. Patients were categorized according to the 8th TNM N subclassification proposal. Histological type, number of resected nodes (#RN) and adjuvant therapy (ADJ) were considered limiting factors. RESULTS: No difference in the 5-year overall survival (-OS) was noted between N1b and N2a1 (49.6% vs 44.8%, P = 0.72); instead, the 5-year-OS was significantly improved in patients with squamous cell carcinoma (63% in N1b vs 30.7% in N2a1, P = 0.04). In patients with ADC, the 5-year-OS was better in those with N2a1 than with N1b (50.6% vs 37.5%, P = 0.09). When we compared N1b with N2a2, the 5-year-OS was statistically significant (49.6% vs 32.8%, P = 0.02); considering only patients with squamous cell carcinoma (63% vs 25.8%, P = 0.003), #RN >10 (63.2% vs 35.3%, P = 0.05) and without ADJ (56.4% vs 24.5%, P = 0.02), the 5-year-OS was significantly different. Differences were not significant for ADC, #RN <10 and ADJ. Finally, the 5-year-OS was statistically significant when we compared N2a1 with N2a2 of the total cohort (44.8% vs 32.8%, P = 0.04), in ADC (5-year-OS 50.6% vs 36.5%, P = 0.04) and #RN >10 (5-year-OS 49.8% vs 32.1%, P = 0.03) without ADJ. CONCLUSIONS: Histological type, ADJ and #RN are relevant prognostic factors in N + non-small-cell lung cancer. Considering these results, we may better interpret the prognosis prediction limits of the proposed 8th TNM subclassification for the N descriptor.
OBJECTIVES: Overlapping survival curves for N1b (multiple N1 stations), N2a2 (single N2 station + N1 involvement) and N2a1 (skip N2 metastasis) limit the current tumour-node-metastasis (TNM) node (N) subclassification for node involvement. We validated externally the proposed subclassification. METHODS: Clinical records from a multicentric database comprising 1036 patients with pulmonary adenocarcinoma (ADC) or squamous cell carcinoma with N1/N2 involvement who underwent, from January 2002 to December 2014, complete lung resections were retrospectively reviewed. Patients were categorized according to the 8th TNM N subclassification proposal. Histological type, number of resected nodes (#RN) and adjuvant therapy (ADJ) were considered limiting factors. RESULTS: No difference in the 5-year overall survival (-OS) was noted between N1b and N2a1 (49.6% vs 44.8%, P = 0.72); instead, the 5-year-OS was significantly improved in patients with squamous cell carcinoma (63% in N1b vs 30.7% in N2a1, P = 0.04). In patients with ADC, the 5-year-OS was better in those with N2a1 than with N1b (50.6% vs 37.5%, P = 0.09). When we compared N1b with N2a2, the 5-year-OS was statistically significant (49.6% vs 32.8%, P = 0.02); considering only patients with squamous cell carcinoma (63% vs 25.8%, P = 0.003), #RN >10 (63.2% vs 35.3%, P = 0.05) and without ADJ (56.4% vs 24.5%, P = 0.02), the 5-year-OS was significantly different. Differences were not significant for ADC, #RN <10 and ADJ. Finally, the 5-year-OS was statistically significant when we compared N2a1 with N2a2 of the total cohort (44.8% vs 32.8%, P = 0.04), in ADC (5-year-OS 50.6% vs 36.5%, P = 0.04) and #RN >10 (5-year-OS 49.8% vs 32.1%, P = 0.03) without ADJ. CONCLUSIONS: Histological type, ADJ and #RN are relevant prognostic factors in N + non-small-cell lung cancer. Considering these results, we may better interpret the prognosis prediction limits of the proposed 8th TNM subclassification for the N descriptor.