Abstract
Background: Cytokines and cytokine receptors contribute importantly to each step of cancer development and progression, and deregulated levels of cytokines and cytokine receptors can be detected in cancer patients locally and systemically. Objective: This review aims to outline and discuss the current status of cytokines and their receptors as potential diagnostic, prognostic, predictive and risk indicators, exemplified in cervical, ovarian, breast, prostate, colorectal, gastric, and non-small cell lung cancers and in sarcomas. Methods: The Medline database was searched for articles on the relevant cancers, published in the English language, using combinations of the following keywords: cytokine, interleukin, growth factor, diagnostic, prognostic, predictive, serum, ascitic and expression. The searches yielded over 2000 papers, and an arbitrary selection of the cited literature was made to present the developments in the field. Results/conclusion: Cytokines, unspecific by definition, present certain patterns of deregulation, often related to clinical characteristics of cancer patients. Some cytokines, most often VEGF, IL-6 and EGFR, present a value of independent prognostic indicators. So far, only local EGFR and HER2 expression assessment in a few cancer types has been accepted for routine use, to qualify patients for a targeted therapy. The authors believe that cytokines may contribute importantly to cancer management in the future; to more likely to indicate prognosis, to identify patients who might benefit from a particular treatment, to monitor treatment response and disease recurrence, and, finally, possibly as part of a larger panel of tumour markers, to improve diagnosis.