Current approach to the management of preoperative iron deficiency anemia in colorectal cancer patients: a review of literature.

<b>Introduction:</b> The prevalence of preoperative anemia is the highest in the group of colorectal cancer (CRC) patients and may reach over 75%. The prevalence of anemia in CRC patients increases even further following surgery. Approximately 75-80% of anemic CRC patients present with absolute or functional iron deficiency (ID). Preoperative anemia constitutes an independent risk factor for allogeneic blood transfusion (ABT), postoperative complications, prolonged length of hospital stay, and increased mortality. ABT is itself associated with increased morbidity and mortality.<b>Aim:</b> The aim of this review article was to present the pathophysiology and the current approach to the diagnostics and treatment of preoperative iron deficiency anemia (IDA) in CRC patients.<b>Material and methods:</b> Extensive search of medical literature databases was performed (Pubmed, Embase). The key words that were used were as follows: CRC, colorectal surgery, ID, IDA, intravenous iron, Patient Blood Management (PBM).<b>Results:</b> There are several laboratory parameters that can be used for IDA diagnosis, however, the simplest and most cost- -effective is reticulocyte hemoglobin equivalent (RET-He). Pathophysiologic features of IDA in CRC patients favor treatment with intravenous, as opposed to oral, iron formulations. Applying PBM strategies minimizes the exposure to ABT.<b>Conclusions:</b> Preoperative IDA is highly prevalent among CRC patients. Preoperative anemia is an independent risk factor for ABT, increased morbidity and mortality, as well as prolonged hospital length of stay. The same negative consequences are associated with ABT. Therefore, preoperative IDA in CRC patients needs to be screened for, diagnosed, and treated before surgery. Effective treatment of preoperative IDA in CRC patients is with intravenous iron formulations. ABT should be the treatment of last resort due to the risk of negative clinical consequences, including an increased rate of cancer recurrence.