Anaesthesia in Cancer Surgery: Can it Affect Cancer Survival?

Surgical removal of a tumor may, ironically, unleash prometastatic effects that enhance cancer recurrence and metastatic disease. The patient's physiologic response to the surgical trauma may increase tumor cell growth and invasiveness while diminishing the immune system's ability to eliminate residual disease. At the same time anaesthetic drugs used to accomplish the surgery may also have important effects on cancer cells and the immune system. Those combined effects potentially lead to sooner recurrence of local or metastatic cancer, and, ultimately, decreased survival. This review explores current research on the influences of surgery and anaesthesia on tumor cells, the immune system, and cancer recurrence. Although a substantial body of evidence sheds much light on the nature of these processes and is at times suggestive of how they might be relevant in clinical practice that literature also reveals a foundation of data that remain largely preclinical with as yet insufficient human study to support clinical recommendations. The tantalizing possibility that anaesthetic care of the surgical oncology patient might affect long term oncologic outcome remains unproven speculation, awaiting prospective human study.