Effect of breast cancer adjuvant therapies on potential biomarkers of pulmonary inflammation.

Background: The aim of this study was to investigate the effect of breast cancer adjuvant therapies on the levels of circulating surfactant protein-D (SP-D), C-Reactive protein (CRP) and soluble receptor for advanced glycation end-products (sRAGE), as potential biomarkers of subclinical pulmonary inflammation.

Materials And Methods: The soluble molecules were serially determined in 38 patients, prior to the initiation of radiation therapy (RT) and during adjuvant treatment, using immunoassays.

Results: Significantly higher levels of all three biomarkers were observed in patients prior to the initiation of RT compared to healthy controls (CRP: p<0.001, SP-D: p<0.05, sRAGE: p<0.05). SP-D levels exhibited a gradual increase after RT and during follow-up (p<0.005). Patients treated with a combination of RT and hormonal therapy presented a significant, but less pronounced, increase in SP-D and a significant decrease in CRP compared to those who did not receive hormonal therapy (p=0.0428 and p=0.0116, respectively). Patients treated with a combination of RT and trastuzumab presented a significant increase in SP-D levels (p=0.0310).

Conclusion: The average rate of change in the levels of circulating SP-D and CRP during postoperative irradiation and adjuvant hormonal therapy suggests that the combined therapeutic regiment may potentially exert important anti-inflammatory effects on the lung. On the contrary, combined administration of RT and trastuzumab is likely to induce or provoke pulmonary inflammation.