Prognostic Significance of C-reactive Protein/Albumin Ratio in Patients with Locally Advanced Unresectable Colorectal Cancer

Despite the poor prognosis of unresectable colorectal cancer (CRC), some patients survive after intensive chemotherapy followed by complete resection of the primary and metastatic tumors. The pretreatment C-reactive protein/albumin ratio (CAR) is a significant prognostic indicator in various carcinomas. Therefore, in this retrospective study, we evaluated the prognostic significance of pretreatment CAR in patients with unresectable CRC. The 61 patients were diagnosed as having initially unresectable disease between January 2004 and December 2013. We analyzed the clinical courses of these patients. Blood samples were taken routinely at their first visit to our hospital. C-reactive protein (CRP), albumin (ALB), and carcinoembryonic antigen (CEA) were analyzed. The median survival time (MST) and 2-year overall survival (OS) of the patients was 9 months (range, 1–96 months) and 23%, respectively. The median CRP, ALB, CAR, and CEA levels of the patients were 2.2 mg/dL, 3.5 g/dL, 0.65, and 20.6 ng/mL, respectively. There was no correlation between CEA levels and the CAR. Patients were divided into two sub-groups using the median CAR level as the cut-off: high CAR (>0.65) and low CAR (≤0.65). Both MST and 2-year OS were significantly lower in the 30 high-CAR patients (4 months, 6.7%) than in the 31 low-CAR patients (13 months, 38.7%, p < 0.001). The primary tumors of three low-CAR patients could be removed after intensive chemotherapy. Thus, low-CAR patients with locally advanced CRC with or without distant metastasis may survive following intensive treatment, even if their tumors were previously deemed to be unresectable.