OBJECTIVEThe aim of this study was to investigate the association between preoperative C-reactive protein (CRP) level and pathologic features in patients with stage I non-small cell lung cancer (NSCLC), and also to analyze if CRP provides prognostic information for NSCLC patients.

METHODSThe clinicopathological data of 105 patients with stage I NSCLC, who underwent pulmonary resection in Shanghai Chest hospital from Mar 1999 to Jul 2004, were retrospectively reviewed. The association between preoperative CRP levels and several clinical variables was analyzed by chi square test. Logistic regression analysis was used for multivariate analysis. Kaplan-Meier method and Cox multivariate regression model was used to examine the prognostic significance of the covariates on survival.

RESULTSAmong the 105 cases, 69 had CRP at normal level (≤ 5 mg/L) and 36 at increased level (> 5 mg/L). The patients who were male (P < 0.001), smoking (P = 0.002), with squamous cell carcinoma (P < 0.001), poor differentiation (P < 0.001), tumor size larger than 3 cm (P < 0.001) had a higher serum CRP level. The maxmal tumor diameter (P = 0.037) was an independent risk factor for preoperative serum CRP level elevation. The five-year survival rate and five-year disease free survival rate of the higher CRP group were lower than that in the normal CRP group (55.6% vs. 79.7%, P < 0.05, and 41.7%vs. 68.1%, P < 0.05, respectively). Cox regression analysis demonstrated that the CRP level had effect on overall survival (P = 0.009) and disease free survival (P = 0.019).

CONCLUSIONSOur findings indicate that the maximal tumor diameter is an independent risk factor for preoperative serum CRP level elevation. The overall survival, disease free survival, five-year survival rate and five-year disease free survival rate of the higher CRP group are lower than that in the normal CRP group.