Perioperative Clinical Interventions That Modify the Immune Response in Cancer Patients

Abstract

The immune system plays a pivotal roleagainst cancer. The development of a successful immune response involves thebalance between the Th1 (antitumor) and Th2 (protumor) responses. Once thisbalance is lost, diseases such as cancer may become apparent. Surgical stress,volatile anaesthetics, opioids and blood transfusions are known to favour a Th2response that manifests as immune suppression. During surgery the load of circulating malignantcancer cells is increasedby tumour manipulation. These cancer cells can migrate and seed in distanttissues and form metastasis. Also, some cancer patients may present withmicrometastasis that may become invasive if left untreated. Therefore, the perioperative period is a moment ofimmunological vulnerability in cancer patients. A better understanding of thefactors that affect the Th1/Th2 balance may allow anaesthesiologists toidentify patients at high risk for cancer recurrence. This review describes theperioperative interventions that can alter the Th1/Th2 balance, during theperioperative period of oncological surgery.