Assessing the relative efficacy of components of opioid-free anaesthesia in adult surgical patients: protocol for a systematic review and component network meta-analysis.

Introduction: The rise of opioid-free anaesthesia (OFA) aims to reduce postoperative pain while reducing opioid-related side effects during surgery. However, the various adjuvant agents used in OFA complicate the evaluation of their effectiveness and risks. Recent reviews question the clinical benefits of OFA, highlighting the need for thorough evaluation.

Antagonists of the Mu-Opioid Receptor in the Cancer Patient: Fact or Fiction?

Purpose Of Review: Antagonists of mu-opioid receptor role in cancer progression remains to be elucidated. The objective of this review was to summarize the available evidence on antagonists of mu-opioid receptor effect on tumor progression and prognosis in different types of cancers and an evaluation of the available findings on their mechanism of action.

Recent Findings: We have found studies related to methylnaltrexone (MNTX) and naltrexone (NTX) usage in cancer outcomes-related setting.

Opioid Receptor Expression in Colorectal Cancer: A Nested Matched Case-Control Study.

Background: There is growing interest in the possible effect of perioperative anesthetic management on the growth and spread of cancer. The impact of perioperative use of opioids on cancer recurrence remains controversial and an assessment cannot yet be established based on current publications. This study aimed to assess the differential expression of opioid receptors between healthy and tumor tissues in patients with stage II and III colorectal cancer undergoing elective surgery by immunohistochemistry (IHC).

Solid Tumor Opioid Receptor Expression and Oncologic Outcomes: Analysis of the Cancer Genome Atlas and Genotype Tissue Expression Project.

Background: Opioid receptors are expressed not only by neural cells in the central nervous system, but also by many solid tumor cancer cells. Whether perioperative opioids given for analgesia after tumor resection surgery might inadvertently activate tumor cells, promoting recurrence or metastasis, remains controversial. We analysed large public gene repositories of solid tumors to investigate differences in opioid receptor expression between normal and tumor tissues and their association with long-term oncologic outcomes.

Mu Opioid Receptor 1 (MOR-1) Expression in Colorectal Cancer and Oncological Long-Term Outcomes: A Five-Year Retrospective Longitudinal Cohort Study.

Preclinical evidence has shown increased expression of mu opioid receptor 1 (MOR-1) in colorectal cancer although its association with disease-free and overall survival (DFS and OS) has not been investigated. We hypothesized that MOR-1 was overexpressed in tumor samples compared to normal tissue and this was associated with decreased DFS and OS. We carried out a retrospective study assessing the association of MOR-1 tumor expression with long-term outcomes by immunohistochemistry in normal and tumor samples from 174 colorectal cancer patients.