GENe EXpression After Regional or General ANesthesia in Patients Undergoing Breast Cancer Surgery

Background: Exposure to general or regional anesthesia, can modulate differently breast cancer biology through a direct activity on cancer cells or indirectly through modifications in host response (immune system, angiogenesis, nervous system). Alterations occur both systemically and locally on the surgical site and is supposed that can affect cancer-related outcomes after months or years. It is not known whether the action of this short exposure to anesthetics on the host and cancer biology is driven by epigenetic alterations in gene and protein expression during the immediate to early post-anesthesia period. An altered gene and protein expression profile may affect the response of the immune system, angiogenesis and the nervous system and induce more or less propitious conditions to tumor progression. Data from studies in animals and humans show that gene expression may change in the brain and heart after only a short exposure to general anesthesia and that changes may persist for several weeks. Methods: The GENEXAN is a randomized, controlled, monocentric, genomic trial aiming to test the hypothesis that regional (paravertebral) anesthesia, compared to general anesthesia, would elicit a differential gene and protein expression pattern in cancer tissue and normal surgical microenvironment after breast cancer surgery in women. Discussion: This research will serve to map gene and protein expression profile after surgery with different anesthetics and elucidate which genes specific to biological systems may affect tumor biology in the immediate operative period. The findings may also address further research depending on the tissue specificity of the up or down-regulated genes.