Background: Adipokines may significantly influence the growth and proliferation of tumor stroma and malignant cells within. Reduced adiponectin and increased leptin serum levels were found in colorectal cancer (CRC) patients. Recently, it has been demonstrated that tumor necrosis factor-alpha (TNF-alpha) is able to induce dose-dependent changes in serum adipokine levels. Thus, aims of this study were to evaluate the possible associations between adipokines, TNF-alpha and clinicopathological variables of CRC patients and to analyze their possible prognostic value in predicting relapse-free and overall survival.
Materials and methods: Baseline leptin, adiponectin and TNF-alpha levels were analyzed in 90 patients with histologically diagnosed primary or newly diagnosed metastatic CRC treated at 'Tor Vergata' Clinical Center and followed up for a median period of 3 years.
Results: Serum leptin levels were higher in CRC patients than in controls (p<0.0001). Conversely, serum adiponectin levels were lower in CRC patients than in controls (p<0.0001). Leptin inversely correlated with adiponectin (p<0.005). The leptin/adiponectin (L/A) ratio was eight-fold greater in CRC compared to controls (p<0.0001). Kaplan-Meier analysis of relapse-free and overall survival time showed that the L/A ratio was an independent predictor for adverse outcome in CRC.
Conclusion: Serum adipokine levels might have a role in the biology of CRC and the combined measurement of leptin and adiponectin levels might provide useful prognostic information in the management of patients with CRC.