Background: Prognostic indicators for non-small cell lung cancer patients traditionally include TNM staging, pleural lavage cytology, and serum carcinoembryonic antigen levels. This prospective study evaluates carcinoembryonic antigen levels in pleural lavage fluid as a potential determinant for patients with lung adenocarcinoma.
Methods: One hundred and fifty patients underwent thoracotomy. Pleural lavage fluid was collected, and pleural lavage cytology and lavage carcinoembryonic antigen levels were determined. The control group included 40 patients with nonmalignant disease.
Results: Sixteen patients (10.7%) had positive pleural lavage cytologies. These patients and those with elevated serum carcinoembryonic antigen levels generally had a poor prognosis. Thirty-seven patients (24.7%), however, showed elevated lavage carcinoembryonic antigen levels, and a significant correlation with patient survival was demonstrated. Multivariate analysis confirmed these results. We also found a correlation between positive pleural lavage cytologies and serum carcinoembryonic antigen levels and patient survival in patients with pN0 disease but not in those with pN1-2 disease. Elevated lavage carcinoembryonic antigen levels, however, correlated significantly with survival rates in patients with pN1-2 disease.
Conclusions: An elevated lavage carcinoembryonic antigen level is an independent prognostic determinant for patients with lung adenocarcinoma, even with advanced disease, and may be a more useful marker of subclinical microdissemination than pleural lavage cytology.