Cancer Recurrence and Regional Anesthesia: The Theories, the Data, and the Future in Outcomes

Abstract

Objective. More than one million people each year in the United States are diagnosed with cancer. Surgery is considered curative, but the perioperative phase represents a vulnerable period for residual disease to spread. Regional anesthesia has been proposed to reduce the incidence of recurrence by attenuating the sympathetic nervous system's response during surgery, reducing opioid requirements thus diminishing their immunosuppressant effects, and providing antitumor and antiinflammatory effects directly through systemic local anesthetic action. In this article, we present a description of the perioperative period, a summary of the proposed hypotheses and available literature on the effects of regional anesthesia on cancer recurrence, and put regional anesthesia in context in regard to its potential role in reducing cancer recurrence during the perioperative period.Methods. A literature review was conducted through PubMed by examining the following topics: effects of surgery on tumor progression, roles of multiple perioperative variables (analgesics, hypothermia, blood transfusion, beta-blockade) in cancer recurrence, and available in vitro, animal, and human studies regarding the effects of regional anesthesia on cancer recurrence.Results. in vitro, animal and human retrospective studies suppport the hypothesis that in certain types of cancer, regional anesthesia may be associated with lower recurrence rates. A few well-planned human randomized clinical trials are currently under way that may provide more solid evidence to substantiate or refute the benefits of regional anesthesia in reducing cancer recurrence.Conclusions. The benefits of regional anesthesia in reducing cancer recurrence have a sound theoretical basis and, in certain cancers, are supported by the existing body of literature. This article outlines the current state of our knowledge on the relationship between cancer progression and regional analgesia.

Risk of second breast cancer events with chronic opioid use in breast cancer survivors

“…μ‐opioid receptor overexpression, which may influence tumor growth and cancer progression, was noted in several cancers including non‐small cell lung, prostate, and breast. However, studies of high morphine doses in mice do not demonstrated tumor progression . Opioids were shown to stimulate angiogenesis in some but not all studies of human endothelial cells and mice .…”

“…Contrary to this, opioids enhance apoptosis in breast cancer, small cell lung cancer, and prostate cancer cells, suggesting opioids may have anticancer effects . Finally, opioids may suppress immune function, in particular natural killer cells, which spontaneously recognize and kill a variety of tumor cells . Opioids may also increase concentrations of vascular endothelial growth factor, which increases angiogenesis and cell migration.…”

“…do not demonstrated tumor progression. 5,6 Opioids were shown to stimulate angiogenesis in some but not all studies of human endothelial cells and mice. 7 Contrary to this, opioids enhance apoptosis in breast cancer, small cell lung cancer, and prostate cancer cells, suggesting opioids may have anticancer effects.…”

“…7 Finally, opioids may suppress immune function, in particular natural killer cells, which spontaneously recognize and kill a variety of tumor cells. [4][5][6][7] Opioids may also increase concentrations of vascular endothelial growth factor, which increases angiogenesis and cell migration. Increases in tumor metastasis with opioids were observed with progression of lung cancer in cell and animal models 8 and with fentanyl in rats.…”

What are the advantages of non-opioid analgesic techniques in the management of acute and chronic pain?

“…In a recently published study [8], investigators reported that for many patients taking opioids before joint replacement surgery, as well as some opioid-naïve patients undergoing arthroplasty procedures, opioid use persisted after surgery despite the absence of joint pain. Retrospective studies have also found an association between the use of large doses of opioid analgesic medication during the perioperative period in patients undergoing primary tumor resections and the recurrence of cancer within 5 years [9].…”