Preoperative and postoperative C-reactive protein (CRP) levels are related to the prognosis for cancer patients. This study aimed to explore the predictive value of combining the two in gastric cancer (GC) patients.
Patients in a clinical trial (NCT02327481) from January 2015 to April 2016 were analyzed. Receiver operating characteristic curves (ROCs) were generated. By calculating the areas under the curve (AUC) and the C-index, the discriminative ability of CRP during different periods were compared, including preoperative (pre-CRP), postoperative days 1, 3, and 5 (post-CRPs) and postoperative maximum CRP (post-CRPmax).
Ultimately, 401 patients were included in this study. The median follow-up time was 42 months (range 3-51 months). For postoperative recurrence, the AUC and C-index of pre-CRP were 0.692 and 0.678, respectively, higher than those for post-CRPs, all p<0.05. Among post-CRPs, post-CRPmax had the highest AUC (0.591) and C-index (0.585). The optimal cut-off values for pre-CRP and post-CRPmax were 3.1mg/L and 77.1mg/L, respectively. Multivariate analysis showed both pre-CRP≥3.1mg/L (high-pre-CRP) and post-CRPmax≥77.1mg/L (high-post-CRPmax) were independent factors for recurrence-free survival (RFS). The model consisting of the pre-CRP, post-CRPmax and TNM had higher predictive ability and clinical utility. Adjuvant chemotherapy (ACT) benefit analysis for stage II/III GC showed patients with pre-CRP<3.1mg/L did not benefit from chemotherapy (RFS:90.0% nonchemotherapy group vs 80.7% chemotherapy group, p=0.557). In the high-pre-CRP group, only patients with high-post-CRPmax but not post-CRPmax<77.1mg/L benefited from chemotherapy (RFS:33.2% nonchemotherapy group vs 49.9% chemotherapy group, p=0.037). Similar findings were observed for overall survival.
Both pre-CRP and post-CRPmax, inexpensively and easily obtained, are independent predictors of recurrence for GC. ACT significantly prolonged the RFS for stage II/III GC with high-pre-CRP and high-post-CRPmax after R0 resection.
The authors.
Scientific and Technological Innovation Joint Capital Projects of Fujian Province.
All authors have declared no conflicts of interest.