Heterogeneity of stage IIIA non-small cell lung cancers (NSCLC) and evaluation of late results of surgical treatment

Abstract

Aims: The aim of the study was assessment of the heterogeneity of stage IIIA non-small cell lung cancers (NSCLC) and the late results of surgical treatment.Methods: The study group consisted of 83 consecutive patients discharged between 1988 and 1992 undergoing radical operative treatment for stage IIIA NSCLC. Squamous cell carcinoma was diagnosed in 54 (65.1%) patients, adenocarcinoma in 23 (27.7%), large cell carcinoma in 2 (2.4%) and mixed (i.e. adenoid-squamous type) in 4 (4.8%). In respect of pTNM staging, 19 (22.9%) patients had T3N1M0, 35 (42.2%) had T2N2M0 and 29 (34.9%) had T3N2M0.Results: Overall, 13.3% of patients with stage IIIA NSCLC survived 5 years following the operation and 8.7% survived 10 years. Analysis of follow-up study indicated that this group was heterogenic. In T3N1M0 group 26.3% survived 5 years following the operation, in T2N2M0 group 14.3%, in T3N2M0 group 3.5% (P=0.015). Of 23 patients with N2 disease and no metastases in hilar lymph nodes (‘skip’ metastases), 26.1% survived 5 years, whereas none of 41 patients with metastases spreading by continuity survived (P=0.0015). If mediastinal lymph node metastases were diagnosed in one level, 25% patients survived 5 years, but if two or more levels were affected, 2.3% only (P=0.0214): 85.7% of patients with well-differentiated (G1) cancer survived 5 years and 62.0% 10 years, whereas among those with moderately differentiated (G2) tumours, 11.8% and 8.8%, respectively. No patient survived 5 years after resection of poorly differentiated (G3) cancer (P<0.001).Conclusions: (1) Patients operated for stage IIIA NSCLC are a heterogeneous group, which makes it difficult to predict late results. (2) Patients operated for stage IIIA NSCLC have a better prognosis if metastases are discovered in level one mediastinal lymph nodes, particularly in the superior part of mediastinum, or if ‘skip’ metastases (pulmonary hilus unaffected) are discovered, as compared to those with N2 disease. (3) Poor histologic differentiation of the tumour is a bad prognostic factor.