OWE-26 Inflammatory responses in patients with colorectal cancer and iron deficiency anaemiatreated with oral iron

Introduction Colorectal cancer (CRC), a major cause of cancer-related mortality, is associated with iron deficiency anaemia (IDA) and is typically treated with oral iron. Iron is an essential nutrient element that is required for a diverse range of biological activities including the immune function (1). However, studies in animal and cell line models have shown that accumulation of iron in the gut can generate toxic reactive oxygen species and proinflammatory cytokines that results in tissue damage and CRC progression (2). We studied, for the first time in humans, the effect of oral (OI) versus intravenous iron (IVI) treatment on iron distribution, immune cell infiltration and systemic cytokine profile in CRC patients with IDA. Methods Patients with CRC and IDA received oral-ferrous sulphate (n=20) or intravenous ferric carboxymaltose (n=20) for 2 weeks. Tissue was analysed for iron loading using Prussian-Blue staining. Tissue cytokine and immune cell distribution was determined using immunohistochemistry. Systemic cytokine production was evaluated by multiplex-cytokine assays. Results Iron expression was distributed to the epithelium of tumour tissues in OI treatment (p Conclusions Intravenous iron is compartmentalised to non-epithelial cells indicating that iron is potentially less bio-available to the tumour cells. Oral iron treatment induces inflammatory immune responses both systemically and within the tumour microenvironment. Further functional studies are ongoing to evaluate the mucosal immune response to differential iron loading. References Bergman M, et al., Biomed Pharmacother. 2005;59(6):307. Glei M, et al., Mutat Res. 2002 26;519(–):151.