Background and purpose: We evaluate if C-reactive protein (CRP) is an objective biomarker of esophageal cancer in patients undergoing radiotherapy.
Materials and methods: Between November 2002 and July 2007, 123 patients undergoing radiotherapy for newly diagnosed esophageal cancer were enrolled. Serum CRP concentration was measured before the initiation of treatment. The relationship between serum CRP levels and other relevant variables such as body mass index, white blood cell count, platelet count, bilirubin, aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), cholesterol, hemoglobin, and albumin levels was also analyzed.
Results: Eighty-one patients of the 123 patients enrolled (65.9%) had elevated CRP levels (5mg/L). The 2-year survival for patients with CRP 5mg/L was 7.8% compared to 78.4% for patients with CRP <5mg/L. Hypoalbuminemia (albumin <3.5g/dL) was also related to shorter survival using univariate analysis. Multivariate analysis demonstrated that only higher serum CRP concentration and hypoalbuminemia were independent prognostic indicators for survival of patients with esophageal cancer.
Conclusions: Pretreatment serum levels of CRP and albumin are objective, easily measurable biomarkers which can be used in combination with conventional staging to accurately predict survival in patients with esophageal cancer treated with radiotherapy.