Serum type III procollagen peptide: Indicator for pulmonary fibrosis I. A tool for early detection of pulmonary fibrosis as a complication in cancer therapy

To clarify whether serum type III procollagen peptide can reflect degree of pulmonary fibrosis and is useful for the early detection of pulmonary fibrosis seen as a complication of cancer therapy, 24 cancer patients were investigated before and after radiation therapy or treatment with anti-cancer drugs. The serum peptide levels in 68 healthy adults was 8.6 ± 2.4 ng/ml (mean ± SD). Before cancer therapy the serum peptide levels in 15 cancer patients without detectab!e liver dysfunction were within normal range. After cancer therapy thirteen cancer patients with complicating pulmonary fibrosis revealed 24.3 ± 8.0 in serum, while the remaining 11 cases without complication of pulmonary fibrosis showed lower values of 16.1 ± 2.5 with statistical significance (p<0.01). There was no correlation between serum peptide level and degree of pulmonary fibrosis. However, the cases showing high values revealed interstitial pneumonitis followed by rapid progressive pulmonary fibrosis caused by radiation therapy or treatment with anti-cancer drugs. These results indicate that this method is useful for detecting the complication of progressive interstitial pulmonary fibrosis at an early stage.