Prognostic impact of baseline serum C-reactive protein in patients with metastatic renal cell carcinoma (RCC) treated with sunitinib
- To evaluate the impact of baseline serum C-reactive protein (CRP) level on outcome in patients with metastatic renal cell carcinoma (mRCC) treated with sunitinib.
Patients and Methods
- We reviewed the charts of patients with mRCC who started sunitinib as a first targeted treatment between 2005 and 2012 in three hospitals in Belgium and France.
- Collected data included known prognostic factors for mRCC, anatomical location of metastatic sites, response rate (RR), progression-free survival (PFS) and overall survival (OS).
- A total of 200 eligible patients were identified by retrospective chart review. The median PFS and OS were 12 and 20 months, respectively.
- We observed a clear impact of baseline CRP levels on outcome: the median PFS was 25 months in the group with baseline CRP ≤5 mg/L and 8 months in the group with baseline CRP >5 mg/L (hazard ratio [HR] 2.48, 95% CI 1.74–3.59). The median OS in each group was 50 vs 12 months, respectively (HR 3.17, 2.20–4.68). In the group with baseline CRP ≤5 mg/L, 61% of patients experienced a partial response compared with 32% of patients in the group with baseline CRP >5 mg/L (difference = 29%, 95% CI 15–42).
- When adding baseline CRP (with a log transformation) to the six variables of the International Metastatic RCC Database Consortium (IMDC) model in a multivariable Cox regression model, baseline CRP was independently associated with poor PFS (HR for each doubling in CRP level: 1.14, 95% CI 1.03–1.26; P = 0.01) and OS (HR: 1.29, 95% CI 1.16–1.43; P < 0.001).
- Adding baseline CRP to the model increased the c-statistic of PFS at 5 years from 0.63 (0.59–0.68) to 0.69 (0.65–0.73), and the c-statistic of OS at 5 years from 0.65 (0.60–0.69) to 0.70 (0.66–0.74).
- Patients with elevated baseline CRP levels had a poor prognosis independent of the IMDC risk group, whereas patients with a low baseline CRP in the IMDC favourable risk group had a very good outcome.
- Baseline serum CRP level is a strong independent variable linked with RR, PFS and OS in patients with mRCC treated with sunitinib.