Elevated tumor markers in patients with pulmonary alveolar proteinosis.

Background: The role of tumor markers in pulmonary alveolar proteinosis (PAP) remains unclear. This study investigated the tumor markers in serum and bronchoalveolar lavage fluid (BALF) in PAP patients and explored the relationship between tumor markers and the severity of PAP.

Methods: We retrospectively reviewed 38 patients with PAP.

Results: Mean serum carcinoembryonic antigen (CEA) and CYFRA21-1 levels were higher than the cut-off values (12.7 ± 17.5 ng/mL and 10 ± 10.66 ng/mL, respectively). Significant correlations were found between levels of CEA and neuron-specific enolase (NSE) in serum and serum lactate dehydrogenase (LDH) values (r=0.60, p<0.001 and r=0.56, p<0.001, respectively). A significant correlation was also observed between levels of squamous cell carcinoma (SCC) in serum and PaO2 and PA-aO2 (r=-0.49 p=0.01 and r=-0.51, p=0.01, respectively). The changes of CEA, SCC and NSE levels were consistent with the changes of LDH and PaO2. The serum levels of CEA, NSE and SCC were significantly lower after whole lung lavage compared with those before (8.7 ± 10.6 vs. 15.7 ± 22, 7.9 ± 5.2 vs. 16.6 ± 11.8, 0.4 ± 0.24 vs. 0.59 ± 0.42; p<0.05, respectively).

Conclusions: Elevated serum tumor marker levels were found in PAP patients. The serum levels of CEA, NSE and SCC may reflect the severity of the disease and predict the therapeutic effect of whole lung lavage.