Background: This study focused on the association between preoperative serum C-reactive protein (CRP) levels and pathologic parameters in patients with resected non-small cell lung cancer (NSCLC). Our primary objective was to find pathologic factors that may explain poor prognosis in patients with preoperative serum CRP elevation.
Methods: The records of 102 patients who had undergone pulmonary resection of NSCLC were reviewed. The association between preoperative serum CRP levels and variables that had p-values of less than 0.05 in t-test or one-way ANOVA was examined using multiple linear regression analysis.
Results: Mean serum CRP level prior to surgery was 3.8+/-4.9 (range, 0.1-19.8) mg/dL. The Pearson correlation coefficient indicated that serum CRP level and pathologic tumor diameter are positively correlated (r=0.487, p<0.001). Serum CRP levels were associated with sex (male vs. female, p=0.003), smoking status (smoker vs. never smoker, p=0.007), histology (squamous vs. non-squamous, p=0.001), tumor size (size>3 cm vs. size< or =3, p<0.001), tumor necrosis (yes vs. no, p<0.001), lymphovascular invasion (yes vs. no, p<0.001), and pleural invasion (P0 vs. P1 vs. P2 vs. P3, p=0.013), but not with age (age>64.5 vs. age< or =64.5, p=0.508), atelectasis or obstructive pneumonia (yes vs. no, p=0.119), location of tumor (peripheral vs. central, p=0.474), and lymph node involvement (N0 vs. N1 vs. N2 vs. N3, p=0.558). Multiple linear regression analysis indicated that pathologic tumor size (beta=0.583, p=0.005) and lymphovascular invasion (beta=3.002, p=0.009) were associated with preoperative serum CRP level.
Conclusion: Our results indicate that lymphovascular invasion and pathologic tumor size are associated with preoperative serum CRP level, which may be considered a prognostic factor in patients with NSCLC. This additional information might serve as a basis to explain poor prognosis in patients with preoperative serum CRP elevation.