Angela Meier, MD, PhD
Assistant Clinical Professor
University of California, San Diego
San Diego, California

Anesthesia and Sex Specific, Immune Dependent Impact on Cancer Progression

The importance of anesthetic choice during tumor surgery in light of its impact on patient survival is emphasized by emerging clinical data. Immune cell infiltration into developing cancers is considered a “hallmark of cancer”, as immune cells comprise a large part of the tumor mass and thus can critically influence tumor progression. The impact of anesthetics on various aspects of the immune system has been observed for decades but remains poorly understood, particularly in the context of cancer. Moreover, sex differences in the immune response to anesthetics have not been described even though male and female immune systems vary drastically. Understanding the interactions between anesthesia, the immune system, sex and cancer is therefore of critical importance to our specialty of anesthesiology as this may significantly impact our patients’ survival. Our preliminary data clearly demonstrate that isoflurane hastens melanoma growth in male mice only and does so in an immune dependent fashion. Our first aim is to demonstrate that not only tumor growth but also metastatic tendencies are impacted by isoflurane in a sex specific manner while our second aim proposes to investigate the role of sex hormones on the impact of volatile anesthesia on tumor progression. Our third aim proposes to investigate the direct effect of volatile anesthesia on fresh human immune cells and to compare male and female human cells with the murine system. Our overall goal is to better understand the impact of volatile anesthesia on our patients’ immune system and how this critically regulates cancer progression and survival. We hypothesize that men and women may be impacted differently due to vastly diverse immune systems. Our findings may significantly impact clinical practice by guiding anesthetic choice and administration during tumor related surgeries and by highlighting the consideration of sex when planning an anesthetic for cancer surgery.