Regional anaesthesia and analgesia: relationship to cancer recurrence and survival.

Cancer treatment is associated with significant morbidity and mortality. Surgery is a mainstay of treatment for many tumours, and anaesthetists care for cancer patients on a daily basis. Surgery itself induces a stress response and inhibits the immune system, and cancer surgery is associated with the release of tumour cells systemically. Preclinical and clinical studies suggest that the anaesthetics and adjuvants given in the perioperative period can affect cancer recurrence and survival, perhaps tipping the balance in some instances to determine whether cancer progresses or regresses. Retrospective studies have hinted that regional anaesthesia can play a protective role in cancer surgery, but many of these studies are small and subject to bias. We eagerly await the results of several large, randomized controlled trials examining the impact of regional anaesthesia and analgesia on cancer recurrence and survival.