The immunosuppressive effects of volatile versus intravenous anesthesia combined with epidural analgesia on kidney cancer: a pilot randomized controlled trial

The impact of inhalation versus total intravenous anesthesia on the immune status in patients undergoing breast cancer surgery: a double-blind randomized clinical trial (TeMP)

Background

Breast cancer (BC) mortality primarily stems from metastases rather than the primary tumor itself. Perioperative stress, encompassing both surgical and anesthetic factors, profoundly impacts the immune system, leading to alterations in neuroendocrine pathways and immune functions, potentially facilitating tumor progression and metastasis. Understanding the immunomodulatory effects of different anesthesia techniques is crucial for optimizing perioperative care in patients with BC. The neutrophil-to-lymphocyte ratio (NLR) serves as one of the key indicators of perioperative immune response.

Objective

To compare the effects of inhalation anesthesia (IA) and total intravenous anesthesia (TIVA) on perioperative immune response in BC surgery patients.

Methods

In this randomized, double-blind clinical trial, BC surgery patients were randomized to receive either TIVA with propofol or IA with sevoflurane. The primary endpoint was NLR assessment. Secondary immune parameters measured included natural killer cells, various T cell subsets, B cells, the immuno-regulatory index [T-helpers (CD3+CD4+)/cytotoxic T-cells (CD3+CD8+)], matrix metallopeptidases (MMP-9), complement components, and immunoglobulins, preoperatively and at 1 and 24 hours postoperatively.

Results

The study included 98 patients (IA: 48, TIVA: 50). The baseline characteristics exhibited remarkable similarity across the groups. No significant difference in absolute NLR values was found between IA and TIVA groups at any time point (1 hour: p = 0.519, 24 hours: p = 0.333). Decreased IgA and IgM levels post-surgery suggested potential negative impacts of IA on humoral immunity compared to TIVA. CRP levels increased more by 24 hours (p = 0.044) in IA compared to TIVA. No significant differences were observed in natural killer cells, T cell subsets, B cells, MMP-9 levels or complement components between groups. Significant differences in the immuno-regulatory index between the TIVA and IA groups at one hour postoperatively (p = 0.033) were not maintained at 24 hours.

Conclusion

While there were no notable differences in NLR among the types of anesthesia, the observed disparities in immunoglobulin content and C-reactive protein levels between groups suggest that we cannot dismiss the potential immunosuppressive effects of inhalational anesthesia in breast cancer surgeries. Further investigation needed to clarify the impact of various anesthesia methods on immune function and their implications for long-term cancer outcomes.

An intravenous anesthetic drug-propofol, influences the biological characteristics of malignant tumors and reshapes the tumor microenvironment: A narrative literature review

Malignant tumors are the second leading cause of death worldwide. This is a public health concern that negatively impacts human health and poses a threat to the safety of life. Although there are several treatment approaches for malignant tumors, surgical resection remains the primary and direct treatment for malignant solid tumors. Anesthesia is an integral part of the operation process. Different anesthesia techniques and drugs have different effects on the operation and the postoperative prognosis. Propofol is an intravenous anesthetic that is commonly used in surgery. A substantial number of studies have shown that propofol participates in the pathophysiological process related to malignant tumors and affects the occurrence and development of malignant tumors, including anti-tumor effect, pro-tumor effect, and regulation of drug resistance. Propofol can also reshape the tumor microenvironment, including anti-angiogenesis, regulation of immunity, reduction of inflammation and remodeling of the extracellular matrix. Furthermore, most clinical studies have also indicated that propofol may contribute to a better postoperative outcome in some malignant tumor surgeries. Therefore, the author reviewed the chemical properties, pharmacokinetics, clinical application and limitations, mechanism of influencing the biological characteristics of malignant tumors and reshaping the tumor microenvironment, studies of propofol in animal tumor models and its relationship with postoperative prognosis of propofol in combination with the relevant literature in recent years, to lay a foundation for further study on the correlation between propofol and malignant tumor and provide theoretical guidance for the selection of anesthetics in malignant tumor surgery.

The benefits of propofol on cancer treatment: Decipher its modulation code to immunocytes

Anesthetics are essential for cancer surgery, but accumulated research have proven that some anesthetics promote the occurrence of certain cancers, leading to adverse effects in the lives of patients. Although anesthetic technology is mature, there is no golden drug selection standard for surgical cancer treatment. To afford the responsibility of human health, a more specific regimen for cancer resection is indeed necessary. Immunosuppression in oncologic surgery has an adverse influence on the outcomes of patients. The choice of anesthetic strategies influences perioperative immunity. Among anesthetics, propofol has shown positive effects on immunity. Apart from that, propofol's anticancer effect has been generally reported, which makes it more significant in oncologic surgery. However, the immunoregulative function of propofol is not reorganized well. Herein, we have summarized the impact of propofol on different immunocytes, proposed its potential mechanism for the positive effect on cancer immunity, and offered a conceivable hypothesis on its regulation to postoperative inflammation. We conclude that the priority of propofol is high in oncologic surgery and propofol may be a promising immunomodulatory drug for tumor therapy.

Expression Profiles of Immune Cells after Propofol or Sevoflurane Anesthesia for Colorectal Cancer Surgery: A Prospective Double-blind Randomized Trial

BACKGROUND

The antitumor effects of natural killer cells, helper T cells, and cytotoxic T cells after cancer surgery were reported previously. This study hypothesized that propofol-based anesthesia would have fewer harmful effects on immune cells than volatile anesthetics-based anesthesia during colorectal cancer surgery.

METHODS

In total, 153 patients undergoing colorectal cancer surgery were randomized and included in the analysis. The primary outcome was the fraction of circulating natural killer cells over time in the propofol and sevoflurane groups. The fractions of circulating natural killer, type 1, type 17 helper T cells, and cytotoxic T cells were investigated. The fractions of CD39 and CD73 expressions on circulating regulatory T cells were investigated, along with the proportions of circulating neutrophils, lymphocytes, and monocytes.

RESULTS

The fraction of circulating natural killer cells was not significantly different between the propofol and sevoflurane groups until 24 h postoperatively (20.4 ± 13.4% vs. 20.8 ± 11.3%, 17.9 ± 12.7% vs. 20.7 ± 11.9%, and 18.6 ± 11.6% vs. 21.3 ± 10.8% before anesthesia and after 1 and 24 h after anesthesia, respectively; difference [95% CI], -0.3 [-4.3 to 3.6], -2.8 [-6.8 to 1.1], and -2.6 [-6.2 to 1.0]; P = 0.863, P = 0.136, and P = 0.151 before anesthesia and after 1 and 24 h, respectively). The fractions of circulating type 1 and type 17 helper T cells, cytotoxic T cells, and CD39+ and CD73+ circulating regulatory T cells were not significantly different between the two groups. The neutrophil to lymphocyte ratio in both groups remained within the normal range and was not different between the groups.

CONCLUSIONS

Propofol-based anesthesia was not superior to sevoflurane-based anesthesia in terms of alleviating suppression of immune cells including natural killer cells and T lymphocytes during colorectal cancer surgery.

EDITOR’S PERSPECTIVE

Transparency considerations for describing statistical analyses in research

Researchers who use the results of statistical analyses to draw conclusions about collected data must write a statistical analysis section in their manuscript. Describing statistical analyses in precise detail is as important as presenting the dosages of drugs and methodology of interventions. It is also essential for scientific accuracy and transparency in scientific research. We evaluated the quality of the statistical analysis sections of clinical research articles published in the Korean Journal of Anesthesiology between February 2020 and February 2021. Using a Likert scale where 1, 2, and 3 represented “not described at all,” “partially described,” and “fully described,” respectively, the following 6 items were assessed: 1) stating of the statistical analysis methods used, 2) rationale for and detailed description of the statistical analysis methods used, 3) parameters derived from the statistical analyses, 4) type and version of the statistical software package used, 5) significance level, and 6) sidedness of the test (one-sided vs. two-sided). The first 3 items evaluate issues directly related to the statistical analysis methods used and last 3 are indirectly related items. In all the included articles, the statistical analysis methods used were stated (score of 3). However, only 4 articles (12.9%) fully described the sidedness of the test (score of 3). Authors tend not to describe the sidedness of statistical analysis tests in the methodology section of clinical research articles. It is essential that the sidedness be described in research studies.