Impact of Regional Anesthesia on Gastroesophageal Cancer Surgery Outcomes: A Systematic Review of the Literature.

Regional anesthesia may play a beneficial role in long-term oncological outcomes. Specifically, it has been suggested that it can prolong recurrence-free survival and overall survival after gastrointestinal cancer surgery, including gastric and esophageal cancer, by modulating the immune and inflammatory response. However, the results from human studies are conflicting. The goal of this systematic review was to summarize the evidence on the impact of regional anesthesia on immunomodulation and cancer recurrence after gastric and esophageal surgery. We conducted a literature search of 5 different databases. Two independent reviewers analyzed the quality of the selected manuscripts according to prespecified inclusion and exclusion criteria. Randomized controlled trials were assessed for potential sources of bias by using the Cochrane Risk of Bias tool. A total of 6 studies were included in the quality analysis and systematic review. A meta-analysis was not conducted for several reasons, including high heterogeneity among studies, low quality of the reports, and lack of standardized outcomes definitions. Although the literature suggests that regional anesthesia has some modulatory effects on the inflammatory and immunological response in the studied patient population, our systematic review indicates that there is no evidence to support or refute the use of epidural anesthesia or analgesia with the goal of reducing cancer recurrence after gastroesophageal cancer surgery.

Impact of Regional Anesthesia on Recurrence, Metastasis, and Immune Response in Breast Cancer Surgery: A Systematic Review of the Literature.

BACKGROUND AND OBJECTIVES: The perioperative period is critical in the long-term prognosis of breast cancer patients. The use of regional anesthesia, such as paravertebral block (PVB), could be associated with improvements in long-term survival after breast cancer surgery by modulating the inflammatory and immune response associated with the surgical trauma, reducing opioid and general anesthetic consumption, and promoting cancer cells death by a direct effect of local anesthetics. METHODS: A systematic literature search was conducted for studies of patients who received PVB for breast cancer surgery. The Jadad score and Ottawa-Newcastle scale were used to assess the methodological quality of randomized controlled trial and observational retrospective studies, respectively. Only high-quality studies were considered for meta-analysis. The selected studies were divided into 3 groups to determine the impact of PVB on (a) recurrence and survival, (b) humoral response, and (c) cellular immune response. RESULTS: We identified 467 relevant studies; 121 of them underwent title and abstract review, 107 were excluded, and 15 studies were selected for full text reading and quality assessment. A meta-analysis was not conducted because of low-quality studies and lack of uniform definition among primary outcomes. Thus, a systematic review of the current evidence was performed. CONCLUSIONS: Our study indicates that there are no data to support or refute the use of PVB for reduction of cancer recurrence or improvement in cancer-related survival. However, PVB use is associated with lower levels of inflammation and a better immune response in comparison with general anesthesia and opioid-based analgesia.