The effect of neuraxial anesthesia on cancer recurrence and survival after cancer surgery: an updated meta-analysis

Anesthetic Approaches and Their Impact on Cancer Recurrence and Metastasis: A Comprehensive Review

Cancer recurrence and metastasis remain critical challenges following surgical resection, influenced by complex perioperative mechanisms. This review explores how surgical stress triggers systemic changes, such as neuroendocrine responses, immune suppression, and inflammation, which promote the dissemination of residual cancer cells and circulating tumor cells. Key mechanisms, such as epithelial-mesenchymal transition and angiogenesis, further enhance metastasis, while hypoxia-inducible factors and inflammatory responses create a microenvironment conducive to tumor progression. Anesthetic agents and techniques modulate these mechanisms in distinct ways. Inhaled anesthetics, such as sevoflurane, may suppress immune function by increasing catecholamines and cytokines, thereby promoting cancer progression. In contrast, propofol-based total intravenous anesthesia mitigates stress responses and preserves natural killer cell activity, supporting immune function. Opioids suppress immune surveillance and promote angiogenesis through the activation of the mu-opioid receptor. Opioid-sparing strategies using NSAIDs show potential in preserving immune function and reducing recurrence risk. Regional anesthesia offers benefits by reducing systemic stress and immune suppression, though the clinical outcomes remain inconsistent. Additionally, dexmedetomidine and ketamine exhibit dual effects, both enhancing and inhibiting tumor progression depending on the dosage and context. This review emphasizes the importance of individualized anesthetic strategies to optimize long-term cancer outcomes. While retrospective studies suggest potential benefits of propofol-based total intravenous anesthesia and regional anesthesia, further large-scale trials are essential to establish the definitive role of anesthetic management in cancer recurrence and survival.

The Role of Anesthetic Management in Lung Cancer Recurrence and Metastasis: A Comprehensive Review

Lung cancer remains a leading cause of cancer-related mortality worldwide. Although surgical treatment is a primary approach, residual cancer cells and surgery-induced pathophysiological changes may promote cancer recurrence and metastasis. Anesthetic agents and techniques have recently been shown to potentially impact these processes by modulating surgical stress responses, immune function, inflammatory pathways, and the tumor microenvironment. Anesthetics can influence immune-modulating cytokines, induce pro-inflammatory factors such as HIF-1α, and alter natural-killer cell activity, affecting cancer cell survival and spread. Preclinical studies suggest volatile anesthetics may promote tumor progression by triggering pro-inflammatory signaling, while propofol shows potential antitumor properties through immune-preserving effects and reductions in IL-6 and other inflammatory markers. Additionally, opioids are known to suppress immune responses and stimulate pathways that may support cancer cell proliferation, whereas regional anesthesia may reduce these risks by decreasing the need for systemic opioids and volatile agents. Despite these findings, clinical data remain inconclusive, with studies showing mixed outcomes across patient populations. Current clinical trials, including comparisons of volatile agents with propofol-based total intravenous anesthesia, aim to provide clarity but highlight the need for further investigation. Large-scale, well-designed studies are essential to validate the true impact of anesthetic choice on cancer recurrence and to optimize perioperative strategies that support long-term oncologic outcomes for lung cancer patients.

Trial watch: local anesthetics in cancer therapy

Preclinical evidence indicates potent antitumor properties of local anesthetics. Numerous underlying mechanisms explaining such anticancer effects have been identified, suggesting direct cytotoxic as well as indirect immunemediated effects that together reduce the proliferative, invasive and migratory potential of malignant cells. Although some retrospective and correlative studies support these findings, prospective randomized controlled trials have not yet fully confirmed the antineoplastic activity of local anesthetics, likely due to the intricate methodology required for mitigating confounding factors. This trial watch aims at compiling all published preclinical and clinical research, along with completed and ongoing trials, that explore the potential antitumor effects of local anesthetics.

Effect of regional versus general anesthesia on recurrence of non-muscle invasive bladder cancer: a systematic review and meta-analysis of eight retrospective cohort studies

BACKGROUND

Regional anesthesia appears to reduce cancer recurrence, but the optimal anesthesia modality for non-muscle invasive bladder cancer (NMIBC) were still under debate. Therefore, we sought to assess the effect of regional and GA only upon the recurrence and long-term prognosis of NMIBC through this meta-analysis.

METHODS

We performed an extensive literature search of PubMed, Embase, Web of Science, the Cochrane Library and China National Knowledge Infrastructure (up to October 30, 2022) to identify eligible articles on the possible impact of different anesthetic modalities for the recurrence rate of NMIBC.

RESULTS

Eight studies comprising 3764 participants, including 2117 subjects with RA and 1647 with GA, were finally enrolled. Cancer recurrence rate was significantly lower in subjects with RA than those with GA (RR 0.84, 95%CI 0.72-0.98, P = 0.03). We didn't detect the differences between GA and RA in the time of recurrence (SMD 2.07, 95% CI -0.49-4.63, P = 0.11) and cancer progression (RR 1.14, 95%CI 0.71-1.84, P = 0.59). Results from subgroup analysis demonstrated that spinal anesthesia could significantly decrease the incidence of cancer recurrence in comparison with general anesthesia (RR 0.80, 95%CI 0.72-0.88, P < 0.001) and high-risk NMIBC patients who received RA tended to have less recurrence (HR 0.55, 95%CI 0.39-0.79, P = 0.001) than those receiving GA.

CONCLUSIONS

RA, especially spinal anesthesia, may be effective in reducing the recurrence rate after transurethral resection of NMIBC. More prospective experimental and clinical studies are needed to validate our findings.

TRIAL REGISTRATION

INPLASY registration INPLASY2022110097.

The effect of opioids on the efficacy of immunotherapy in recurrent/metastatic squamous cell carcinoma of the head and neck

OBJECTIVES

Head and neck squamous cell carcinoma (HNSCC) causes severe pain and opioids, the mainstay of pain management, may have immunomodulatory effects. We evaluated the effect of opioids on immunotherapy efficacy in recurrent/metastatic (R/M) HNSCC patients.

MATERIALS AND METHODS

In a retrospective study of 66 R/M HNSCC patients from 2015 to 2020, opioid dosage, calculated as mean morphine milligram equivalent per day, was assessed on the day of anti-PD-1 monoclonal antibody (mAb) treatment and most recent prior visit. Intratumoral T cells were evaluated by single cell RNAseq and immunohistochemistry prior to treatment. Univariable and multivariable Cox proportional hazards and logistic regression models were used to estimate the association between opioid usage, progression-free survival (PFS), overall survival (OS), disease control rate.

RESULTS

Patients were 79% male, 35% oropharynx, 35% oral cavity, 40% locoregional recurrence, and 56% platinum failure. Higher opioid dosage by continuous variable was significantly associated with lower PFS (p = 0.016) and OS (p < 0.001). In multivariable analysis, including platinum failure status and PD-L1, higher opioids were associated with lower OS. Opioid usage by categorical variable was associated with significantly lower intratumoral CD8+ T cells. Opioid receptor, OPRM1, expression was identified in intratumoral and circulating T cells.

CONCLUSIONS

In our study cohort of anti-PD-1 mAb treatment in R/M HNSCC patients, higher opioids were associated with significantly lower PFS and OS and lower CD8+ T cells in the tumor microenvironment. To our knowledge, this is the first analysis in R/M HNSCC patients and further research into the clinical and biologic effect of opioids is warranted.

Regional anesthesia did not improve postoperative long-term survival of tumor patients: a systematic review and meta-analysis of randomized controlled trials

OBJECTIVE

Experimental research and clinical trials have reported a positive effect of regional anesthesia (RA) on prognosis of cancers. We systematically reviewed the efficacy of RA on recurrence-free survival (RFS) and overall survival (OS) after oncology surgeries.

METHODS

PubMed, Cochrane library, and Embase were searched from inception to June 20, 2022 for RCTs in which any form of RA was initiated perioperatively. Time-to-event data (hazard ratio (HR)) were extracted independently and in duplicate. The primary outcome was the association of RA with RFS and OS, while the secondary outcomes included time to tumor progression, 5-year RFS, and 5-year OS.

RESULTS

Fifteen RCTs with 5981 participants were included. Compared to GA, RA has no positive effect on RFS (HR, - 0.02; 95% CI, - 0.11 to 0.07), OS (HR, - 0.03; 95% CI, - 0.28 to 0.23), time to tumor progression (0.11; 95% CI, - 0.33 to 0.55), 5-year RFS (risk ratio (RR), 1.24; 95% CI, 0.88 to 1.76)), and 5-year OS (RR, 1.11; 95% CI, 0.85 to 1.44). Subgroup analysis based on study design, patient characteristics and tumor types also showed no effect of RA on RFS or OS.

CONCLUSIONS

Our results demonstrated that there is no significant evidence supporting the role of RA in improving long-term survival after oncology surgeries.

Comparison of volatile/inhalational and IV anesthesia in long-term survival of patients with breast cancer: a retrospective study

OBJECTIVE

Breast cancer is a worldwide health concern, and surgical removal has remained the preferred therapeutic option in most patients. Furthermore, the current study was designed to investigate the disease-free survival and overall survival in breast cancer patients, who receive either propofol or isoflurane during operation.

METHOD

This retrospective study was conducted on 994 patients (IV group, n = 530; volatile/inhalational group, n = 464) who underwent breast cancer operation from January 2006 to December 2016 at Faghihi Hospital, Shiraz, Iran. All studied patients were followed up till 2020. Patients are classified into two groups, IV and volatile/inhalational, according to the received anesthesia. For statistical analysis, The Cox regression test was conducted to investigate the association between factors affecting the recurrence of the disease and the Log Rank test was utilized to assess the patients' survival. Finally, to reduce the effect of confounding factors, all patients were matched according to age, tumor size and tumor grade.

RESULTS

Based on results from the log-rank test, the volatile/inhalational group had a better recurrence-free survival (P = 0.039) compared to the total IV group. However, the overall survival was not considerably different (P = 0.520).

CONCLUSION

The current study showed that although 2-year disease-free survival is higher in the volatile/inhalational group, there is no meaningful association between the 5-year overall survival and anesthesia technique.

Local anesthetics and immunotherapy: a novel combination to fight cancer

Intratumoral injection of oncolytic agents such as modified herpes simplex virus T-VEC or local administration of non-viral oncolytic therapies (such as radiofrequency, chemoembolization, cryoablation, or radiotherapy) can activate an anticancer immune response and hence trigger abscopal effects reducing secondary lesions. Preliminary data suggested that oncolytic treatments modulate tumor-infiltrating immune effectors and can be advantageously combined with the immune checkpoint inhibitors. Recent findings indicate that local anesthetics, which are usually used in the clinics to control surgical pain, also possess antineoplastic effects mimicking oncolytic treatments if they are injected into malignant lesions. Moreover, the association of local anesthetics with systemic immune checkpoint inhibition significantly improved overall survival in several preclinical tumor models. This may be explained by direct cytotoxic activity of local anesthetics and additional immune-related abscopal effects. We also summarize the molecular and cellular mechanisms by which the combination of local anesthetics and immunotherapy improves tumor control by the immune system.

Impact of local anesthetics on epigenetics in cancer

Defective silencing of tumor suppressor genes through epigenetic alterations contributes to oncogenesis by perturbing cell cycle regulation, DNA repair or cell death mechanisms. Reversal of such epigenetic changes including DNA hypermethylation provides a promising anticancer strategy. Until now, the nucleoside derivatives 5-azacytidine and decitabine are the sole DNA methyltransferase (DNMT) inhibitors approved by the FDA for the treatment of specific hematological cancers. Nevertheless, due to their nucleoside structure, these inhibitors directly incorporate into DNA, which leads to severe side effects and compromises genomic stability. Much emphasis has been placed on the development of less toxic epigenetic modifiers. Recently, several preclinical studies demonstrated the potent epigenetic effects of local anesthetics, which are routinely used during primary tumor resection to relief surgical pain. These non-nucleoside molecules inhibit DNMT activity, affect the expression of micro-RNAs and repress histone acetylation, thus exerting cytotoxic effects on malignant cells. The in-depth mechanistic comprehension of these epigenetic effects might promote the use of local anesthetics as anticancer drugs.

Lidocaine promotes apoptosis in breast cancer cells by affecting VDAC1 expression

OBJECTIVE

To investigate the effect of lidocaine on the expression of voltage-dependent anion channel 1 (VDAC1) in breast invasive carcinoma (BRCA) and its impact on the apoptosis of breast cancer cells.

METHODS

We collected clinical data from patients with invasive breast cancer from 2010 to 2020 in the First affiliated hospital of Nanchang University, evaluated the prognostic value of VDAC1 gene expression in breast cancer, and detected the expression of VDAC1 protein in breast cancer tissues and paracancerous tissues by immunohistochemical staining of paraffin sections. Also, we cultured breast cancer cells (MCF-7) to observe the effect of lidocaine on the apoptosis of MCF-7 cells.

RESULTS

Analysis of clinical data and gene expression data of BRCA patients showed VDAC1 was a differentially expressed gene in BRCA, VDAC1 may be of great significance for the diagnosis and prognosis of BRCA patients. Administration of lidocaine 3 mM significantly decreased VDAC1 expression, the expression of protein Bcl-2 was significantly decreased (p < 0.05), and the expression of p53 increased significantly (p < 0.05). Lidocaine inhibited the proliferation of MCF-7 breast cancer cells, increased the percentage of G2 / M phase cells and apoptosis.

CONCLUSION

Lidocaine may inhibit the activity of breast cancer cells by inhibiting the expression of VDAC1, increasing the apoptosis in breast cancer cells.

Impact of Local Anesthetics on Cancer Behavior and Outcome during the Perioperative Period: A Review

There is a growing interest regarding the impact of the perioperative period and the application of anesthetic drugs on the recurrence of cancer metastases. Among them, the use of amide-type local anesthetics seems promising since in vitro studies and animal models have shown their potential to inhibit the Intercellular Adhesion Molecule 1 (ICAM-1) expression and Src activity, which are clearly implicated in the process of inflammation and cancer metastases. This review emphasizes the potential of amide-type local anesthetics in this context.

Lidocaine Suppresses Gastric Cancer Development Through Circ_ANO5/miR-21-5p/LIFR Axis

BACKGROUND

Lidocaine has been manifested to exert anti-tumor role in gastric cancer (GC) progression. However, the action mechanism by which Lidocaine functions in GC has not been fully elucidated.

AIM

The study aimed to reveal the molecular mechanism of Lidocaine in GC progression.

METHODS

Cell clonogenicity and viability were assessed by colony formation and methyl thiazolyl tetrazolium assays, respectively. Transwell assay was employed to detect cell migration and invasion. Flow cytometry was implemented to monitor cell apoptosis. Relative expression of circular RNA ANO5 (circ_ANO5), microRNA (miR)-21-5p and Leukemia inhibitory factor receptor (LIFR) was examined by quantitative reverse transcription-polymerase chain reaction. Western blot assay was performed to analyze the levels of LIFR and cell metastasis-related proteins. The target relationship between miR-21-5p and circ_ANO5 or LIFR was confirmed by dual-luciferase reporter assay. In addition, xenograft model was established to explore the role of Lidocaine in vivo.

RESULTS

Lidocaine inhibited cell proliferation, migration and invasion, while promoted apoptosis of GC cells. Lidocaine upregulated circ_ANO5 and LIFR expression, but downregulated miR-21-5p expression in GC cells. Additionally, expression of circ_ANO5 and LIFR was decreased, while miR-21-5p expression was increased in GC cells. Circ_ANO5 depletion or miR-21-5p overexpression attenuated Lidocaine-induced anti-proliferative and anti-metastatic effects on GC cells. Circ_ANO5 could sponge miR-21-5p, and miR-21-5p targeted LIFR. Moreover, Lidocaine suppressed the tumor growth in vivo.

CONCLUSION

Lidocaine might GC cell malignancy by modulating circ_ANO5/miR-21-5p/LIFR axis, highlighting a novel insight for GC treatment.

Local anesthetics elicit immune-dependent anticancer effects

BACKGROUND

Retrospective clinical trials reported a reduced local relapse rate, as well as improved overall survival after injection of local anesthetics during cancer surgery. Here, we investigated the anticancer effects of six local anesthetics used in clinical practice.

RESULTS

In vitro, local anesthetics induced signs of cancer cell stress including inhibition of oxidative phosphorylation, and induction of autophagy as well as endoplasmic reticulum (ER) stress characterized by the splicing of X-box binding protein 1 (XBP1s) mRNA, cleavage of activating transcription factor 6 (ATF6), phosphorylation of eIF2α and subsequent upregulation of activating transcription factor 4 (ATF4). Both eIF2α phosphorylation and autophagy required the ER stress-relevant eukaryotic translation initiation factor 2 alpha kinase 3 (EIF2AK3, best known as PERK). Local anesthetics also activated two hallmarks of immunogenic cell death, namely, the release of ATP and high-mobility group box 1 protein (HMGB1), yet failed to cause the translocation of calreticulin (CALR) from the ER to the plasma membrane. In vivo, locally injected anesthetics decreased tumor growth and improved survival in several models of tumors established in immunocompetent mice. Systemic immunotherapy with PD-1 blockade or intratumoral injection of recombinant CALR protein, increased the antitumor effects of local anesthetics. Local anesthetics failed to induce antitumor effects in immunodeficient mice or against cancers unable to activate ER stress or autophagy due to the knockout of EIF2AK3/PERK or ATG5, respectively. Uncoupling agents that inhibit oxidative phosphorylation and induce autophagy and ER stress mimicked the immune-dependent antitumor effects of local anesthetics.

CONCLUSION

Altogether, these results indicate that local anesthetics induce a therapeutically relevant pattern of immunogenic stress responses in cancer cells.

Less Well-Known Consequences of the Long-Term Use of Opioid Analgesics: A Comprehensive Literature Review

BACKGROUND

The adverse effects of short-term opioid analgesics are well known and acknowledged; however, the spectrum of the sequelae of long-term use seems less clear. Some effects may remain undetected but still have the potential to cause harm and reduce patients' quality of life.

OBJECTIVE

To review the literature on the adverse effects of long-term opioid therapy.

METHODS

We performed a quasi-systematic search, analyzing articles published in the MEDLINE database between January 2000 and March 2021 that identified adverse effects of opioids used for chronic pain treatment.

RESULTS

Growing evidence indicates that there are multiple serious adverse effects of opioid treatment. Long-term opioid use may have significant effects on the endocrine, immune, cardiovascular, respiratory, gastrointestinal, and neural systems. Studies show that long-term opioid treatment increases the risk of fractures, infections, cardiovascular complications, sleep-disordered breathing, bowel dysfunction, overdose, and mortality. Opioids may potentially affect cancer development. Most consequences of the long-term use of opioids have been identified in studies of patients with non-malignant pain.

CONCLUSION

Studies indicate that long-term use of opioids increases the risk of drug-related events in a significant number of patients. Clinicians should be aware of these complications associated with prescribing opioids, discuss them with patients, prevent complications, if possible, and diagnose them early and manage adequately. More human studies are needed to assess the risk, including trials with individual opioids, because they have different adverse effect profiles.

Anesthesia With Propofol Sedation Reduces Locoregional Recurrence in Patients With Breast Cancer Receiving Total Mastectomy Compared With Non-Propofol Anesthesia

Purpose

We examined locoregional recurrence (LRR) in patients with breast invasive ductal carcinoma (IDC) receiving total mastectomy (TM) under propofol-based paravertebral block-regional anesthesia (PB-RA) versus sevoflurane-based inhalational general anesthesia (INHA-GA) without propofol. All-cause death and distant metastasis were secondary endpoints.

Patients and Methods

Patients with breast IDC receiving TM were recruited through propensity score matching and categorized into INHA-GA with sevoflurane and PB-RA with propofol groups. Cox regression analysis was performed to calculate hazard ratios (HRs) and 95% confidence intervals (CIs).

Results

In the multivariate Cox regression analysis, the adjusted HR (aHR; 95% CI) of LRR for the PB-RA with propofol group was 0.52 (0.28–0.96) compared with the INHA-GA with sevoflurane group. The aHRs of LRR for differentiation grade II, grade III, the American Joint Committee on Cancer clinical stage II, stage III, pathological tumor (pT) stage 2, pT stage 3–4, pathological nodal (pN) stage 1, and pN stage 2–3 were 1.16 (1.04–2.08), 1.28 (1.07–2.12), 3.71 (1.82–7.59), 4.67 (1.65–13.18), 1.09 (1.02–1.21), 1.17 (1.03–2.16), 1.10 (1.03–1.33), and 1.22 (1.06–2.41), respectively, compared with differentiation grade I, clinical stage I, pT1, and pN0. The aHR of LRR for adjuvant RT was 0.88 (0.64–0.94) compared with that for no adjuvant RT.

Conclusion

PB-RA with propofol might be beneficial for reducing LRR in women with breast IDC receiving TM compared with INHA-GA without propofol.

Anesthesia and Oncology: Friend or Foe?

Cancer is a leading cause of death, and surgery is an important treatment modality. Laboratory research and retrospective studies have raised the suspicion that the choice of anesthetics for cancer surgery might affect the course of cancerous disease. The aim of this review is to provide a critical overview of the current state of knowledge. Inhalational anesthesia with volatiles or total intravenous anesthesia (TIVA) with propofol are the two most commonly used anesthetic techniques. Most data comparing volatile anesthetics with TIVA is from either in vitro or retrospective studies. Although conflicting, data shows a trend towards favoring propofol. Opioids are commonly used in anesthesia. Data on potential effects of opioids on growth and recurrence of cancer are scarce and conflicting. Preclinical studies have shown that opioids stimulate cancer growth through the µ-opioid receptor. Opioids also act as immunosuppressants and, therefore, have the potential to facilitate metastatic spread. However, the finding of an adverse effect of opioids on tumor growth and cancer recurrence by some retrospective studies has not been confirmed by prospective studies. Regional anesthesia has not been found to have a beneficial effect on the outcome of surgically treated cancer patients, but prospective studies are scarce. Local anesthetics might have a beneficial effect, as observed in animal and in vitro studies. However, prospective clinical studies strongly question such an effect. Blood products, which may be needed during extensive cancer surgery suppress the immune system, and data strongly suggest a negative impact on cancer recurrence. The potential effects of other commonly used anesthetic agents on the outcome of cancer patients have not been sufficiently studied for drawing valid conclusions. In conclusion, laboratory data and most retrospective studies suggest a potential advantage of TIVA over inhalational anesthesia on the outcome of surgical cancer patients, but prospective, randomized studies are missing. Given the state of weak scientific evidence, TIVA may be used as the preferred type of anesthesia unless there is an individual contraindication against it. Studies on the effects of other drugs frequently used in anesthesia are limited in number and quality, and have found conflicting results.

Direct Cytotoxic and Indirect, Immune-Mediated Effects of Local Anesthetics Against Cancer

Local anesthetics are frequently employed during surgery in order to control peri- and postoperative pain. Retrospective studies have revealed an unexpected correlation between increased long-term survival and the use of local anesthetics during oncological surgery. This effect of local anesthetics might rely on direct cytotoxic effects on malignant cells or on indirect, immune-mediated effects. It is tempting to speculate, yet needs to be formally proven, that the combination of local anesthetics with oncological surgery and conventional anticancer therapy would offer an opportunity to control residual cancer cells. This review summarizes findings from fundamental research together with clinical data on the use of local anesthetics as anticancer standalone drugs or their combination with conventional treatments. We suggest that a better comprehension of the anticancer effects of local anesthetics at the preclinical and clinical levels may broadly improve the surgical treatment of cancer.

Epidural Analgesia and Recurrence after Colorectal Cancer Surgery: A Danish Retrospective Registry-based Cohort Study

BACKGROUND

Surgery is the main curative treatment for colorectal cancer. Yet the immunologic and humoral response to surgery may facilitate progression of micro-metastases. It has been suggested that epidural analgesia preserves immune competency and prevents metastasis formation. Hence, the authors tested the hypothesis that epidural analgesia would result in less cancer recurrence after colorectal cancer surgery.

METHODS

The Danish Colorectal Cancer Group Database and the Danish Anesthesia Database were used to identify patients operated for colorectal cancer between 2004 and 2018 with no residual tumor tissue left after surgery. The exposure group was defined by preoperative insertion of an epidural catheter for analgesia. The primary outcome was colorectal cancer recurrence, and the secondary outcome was mortality. Recurrences were identified using a validated algorithm based on data from Danish health registries. Follow-up was until death or September 7, 2018. The authors used propensity score matching to adjust for potential preoperative confounders.

RESULTS

In the study population of 11,618 individuals, 3,496 (30.1%) had an epidural catheter inserted before surgery. The epidural analgesia group had higher proportions of total IV anesthesia, laparotomies, and rectal tumors, and epidural analgesia was most frequently used between 2009 and 2012. The propensity score-matched study cohort consisted of 2,980 individuals in each group with balanced baseline covariates. Median follow-up was 58 months (interquartile range, 29 to 86). Recurrence occurred in 567 (19.0%) individuals in the epidural analgesia group and 610 (20.5%) in the group without epidural analgesia. The authors found no association between epidural analgesia and recurrence (hazard ratio, 0.91; 95% CI, 0.82 to 1.02) or mortality (hazard ratio, 1.01; 95% CI, 0.92 to 1.10).

CONCLUSIONS

In colorectal cancer surgery, epidural analgesia was not statistically significantly associated with less cancer recurrence.

EDITOR’S PERSPECTIVE

Can Acute Postoperative Pain Management After Tumour Resection Surgery Modulate Risk of Later Recurrence or Metastasis?

Background

Cancer is a leading cause of mortality worldwide, but death is rarely from the primary tumour: Rather it is multi-organ dysfunction from metastatic disease that is responsible for up to 90% of cancer-related deaths. Surgical resection of the primary tumour is indicated in 70% of cases. The perioperative stress response, tissue hypoxia at the site of surgery, and acute pain contribute to immunosuppression and neo-angiogenesis, potentially promoting tumour survival, proliferation, and metastasis. Poorly controlled acute postoperative pain decreases Natural Killer (NK) immune cell activity, which could potentially facilitate circulating tumour cells from evading immune detection. This consequently promotes tumour growth and distal metastasis.

Methods

We conducted a comprehensive literature search for links between acute pain and cancer outcomes using multiple online databases. Relevant articles from January 1st, 2010 to September 1st, 2021 were analysed and appraised on whether postoperative pain control can modulate the risk of recurrence, metastasis, and overall cancer survival.

Results

Although experimental and retrospective clinical data suggest a plausible role for regional anaesthesia in cancer outcome modulation, this has not been supported by the single, largest prospective trial to date concerning breast cancer. While there are mixed results on anaesthesiology drug-related interventions, the most plausible data relates to total intravenous anaesthesia with propofol, and to systemic administration of lidocaine.

Conclusion

The hypothesis that anaesthetic and analgesic technique during cancer surgery could influence risk of subsequent recurrence or metastasis has been prevalent for >15 years. The first, large-scale definitive trial among women with breast cancer found robust equivalent findings between volatile anaesthesia with opioid analgesia and regional anaesthesia. Therefore, while regional anaesthesia during tumour resection does not seem to have any effect on cancer outcomes, it remains plausible that other anaesthetic techniques (e.g. total intravenous anaesthesia and systemic lidocaine infusion) might influence oncologic outcome in other major tumour resection surgery (e.g. colorectal and lung). Therefore, another large trial is needed to definitively answer these specific research questions. Until such evidence is available, perioperative analgesia for cancer surgery of curative intent should be based on patient co-morbidity and non-cancer endpoints, such as optimising analgesia and minimising postoperative complications.

Ambulatory surgery for cancer patients: current controversies and concerns

PURPOSE OF REVIEW

This review aims to describe the main concerns and controversies of ambulatory surgery in cancer patients while providing an overview of ambulatory cancer anaesthesia.

RECENT FINDINGS

Cancer patients can undergo a variety of ambulatory surgeries. The introduction of robotic approach and the implementation of enhanced recovery programmes have allowed patients to avoid hospital admissions after more complex or invasive surgeries. In this context, the anaesthesiologist plays a key role in ensuring that the ambulatory surgical centre or the hospital-based ambulatory department is equipped for the perioperative challenges of the cancer population. Cancer patients tend to be older and with more comorbidities than the general population. In addition, these individuals may suffer from chronic conditions solely because of the cancer itself, or the treatment. Consequently, frailty is not uncommon and should be screened on a routine basis. Regional analgesia plays a key role in the provision of opioid-sparing multimodal analgesia.

SUMMARY

Neither regional anaesthesia or general anaesthesia have proven to affect the long-term oncological outcomes of cancer patients undergoing ambulatory surgery. In addition, there is insufficient evidence to suggest the use of total intravenous anaesthesia or inhalational anaesthesia over the other to decrease cancer recurrence.

Advances in Oncoanaesthesia and Cancer Pain

INTRODUCTION

The growing interest on how peri-‑operative interventions, especially regional anesthesia, during cancer surgery can alter oncological outcome increasing disease free survival is probably responsible for the birth of the new subspecialty called onco-anesthesia. A paradigm shift in the concept of anesthetic management has occurred recently owing to the innumerable diverse revelations from the ongoing research in this field.

DISCUSSION

Long lasting but reversible epigenetic changes can occur due to surgical stress and perioperative anesthetic medications. The exact relationship between these factors and tumor biology is being studied further. A popular topic under research now is the influence of regional anesthesia on cancer recurrence. Combining nerve blocks with total intravenous anesthesia (TIVA) brings down the requirement of opioids and volatile anesthetic agents implicated in cancer recurrence. The study of mechanism of pain at the molecular level has led to the discovery of novel modes of prevention of chronic post-surgical pain. Newer combination aggressive treatment therapies -intraoperative chemotherapy and radiotherapy, isolated limb perfusion, photodynamic therapy and robotic surgery require specialized anesthetic management. The COVID pandemic introduced new guidelines for safe management of oncosurgical patients .Use of genomic mapping to personalize pain management will be the breakthrough of the decade.

CONCLUSION

The discovery that anesthetic strategy could have significant oncological sequel is a quantum leap forward. Avoiding some anesthetic medications may decrease cancer recurrence. Comprehensive cancer care and translational research will pave the way to uncover safe anesthetic practices.

Anesthetic care influences long-term outcomes: What is the evidence?

Despite advances in cancer therapy surgery remains one of the most important treatments for solid tumors; however, even with the development of better and less invasive surgical techniques, surgery is characterized by the increased risk of tumor metastasis, accelerated growth of pre-existing micrometastasis and cancer recurrence. Total intravenous anesthesia (TIVA) and regional anesthesia have been proposed to improve long-term outcomes after cancer surgery by different mechanisms, including attenuation of the neuroendocrine response, immunosuppression, decreased opioid requirements (opioids promote angiogenesis and tumor growth) and avoidance of volatile inhalational agents. Much of the data that support these ideas originate from laboratory studies, while there is no clear consensus from the retrospective cohort studies to date. Several randomized controlled trials (RCTs) are in progress and may provide a better understanding regarding the role of the anesthesiologist in cancer surgery. The purpose of this review is to summarize the experimental and human data regarding the effect of anesthesia agents and anesthesia techniques on cancer outcomes.

Paravertebral block in regional anesthesia with propofol sedation reduces locoregional recurrence in patients with breast cancer receiving breast conservative surgery compared with volatile inhalational without propofol in general anesthesia

PURPOSE

We examined locoregional recurrence (LRR) in patients with breast invasive ductal carcinoma (IDC) receiving breast conservative surgery (BCS) under propofol-based paravertebral block-regional anesthesia (PB-RA) versus sevoflurane-based inhalational general anesthesia (INHA-GA) without propofol. All-cause death and distant metastasis were secondary endpoints.

PATIENTS AND METHODS

Patients with breast IDC receiving BCS were recruited through propensity score matching and categorized into INHA-GA with sevoflurane and PB-RA with propofol groups. Cox regression analysis was performed to calculate hazard ratios (HRs) and 95% confidence intervals (CIs).

RESULTS

In the multivariate Cox regression analysis, the adjusted HR (aHR; 95% CI) of LRR for the PB-RA with propofol group was 0.67 (0.46-0.99) compared with the INHA-GA with sevoflurane group. The aHRs of LRR for differentiation grade II, grade III, the American Joint Committee on Cancer clinical stage II, stage III, pathological tumor (pT) stage 2, pT stage 3-4, pathological nodal (pN) stage 2-3, and Her-2 positivity were 1.87 (1.03-3.42), 2.31 (1.20-4.44), 1.67 (1.09-2.56), 2.43 (1.18-4.97), 1.17 (1.03-1.19), 1.28 (1.13-2.24), 1.20 (1.05-2.22), and 1.59 (1.01-2.51), respectively, compared with those for differentiation grade I, clinical stage I, pT1, pN0, and HER-2 negativity. The aHR of LRR for adjuvant radiotherapy was 0.60 (0.38-0.97) compared with that for no adjuvant radiotherapy.

CONCLUSION

PB-RA with propofol might be beneficial for reducing LRR in women with breast IDC receiving BCS compared with INHA-GA without propofol.

Effects of 2-Hydroxypropil-Β-Cyclodextrin-Lidocaine on Tumor Growth and Inflammatory Response

BACKGROUND

Antiproliferative and cytotoxic effects of lidocaine have been reported in tumor cells. However, the use of these drugs is restricted due to their short action with rapid dispersion from the injected site. The complexation of local anesthetics in 2-hydroxypropyl-β-cyclodextrin (HP-β-CD) is able to improve pharmacological features.

OBJECTIVE

This study evaluated the antitumor effects of lidocaine and the complex HP-β-CD-lidocaine (HP-β-CD-lido).

METHODS

In vitro;, human adenocarcinoma (HeLa) and keratinocytes (HaCaT) were exposed to lidocaine formulations and cell viability, proliferation and apoptosis induction were measured. In vivo;, Walker 256 carcinoma cells were subcutaneously injected into the plantar region of the rat right hind paw. The animals were treated with a local application of 5% lidocaine or 5% HP-β-CD-lido. Doxorubicin (3 mg/Kg/day, intraperitoneal) was used as a positive control. Edema sizes were measured daily and the release of cytokines (TNF-α, IL-1α and CXCL-1) and prostaglandin E2 was evaluated. Histological analysis was also performed.

RESULTS

HaCaT IG50 values were 846 μM and 2253 μM for lido and HP-β-CD-lido, respectively. In HeLa cells, the IG50 was 1765 μM for lido and 2044 μM for HP-β-CD-lido. Lidocaine formulations significantly reduced the paw edema on day 6 after Walker 256 cells inoculation. However, there were no differences in the release of inflammatory mediators in comparison to the control group.

CONCLUSION

Lidocaine formulations were able to reduce the edema in vivo;, without affecting the tumor- induced inflammatory response. The antiproliferative effects of lidocaine formulations may have contributed to tumor reduction.

The Intersection of Regional Anesthesia and Cancer Progression: A Theoretical Framework

The surgical stress and inflammatory response and volatile anesthetic agents have been shown to promote tumor metastasis in animal and in-vitro studies. Regional neuraxial anesthesia protects against these effects by decreasing the surgical stress and inflammatory response and associated changes in immune function in animals. However, evidence of a similar effect in humans remains equivocal due to the high variability and retrospective nature of clinical studies and difficulty in directly comparing regional versus general anesthesia in humans. We propose a theoretical framework to address the question of regional anesthesia as protective against metastasis.

This theoretical construct views the immune system, circulating tumor cells, micrometastases, and inflammatory mediators as distinct populations in a highly connected system. In ecological theory, highly connected populations demonstrate more resilience to local perturbations but are prone to system-wide shifts compared with their poorly connected counterparts. Neuraxial anesthesia transforms the otherwise system-wide perturbations of the surgical stress and inflammatory response and volatile anesthesia into a comparatively local perturbation to which the system is more resilient. We propose this framework for experimental and mathematical models to help determine the impact of anesthetic choice on recurrence and metastasis and create therapeutic strategies to improve cancer outcomes after surgery.

Anesthetic Management for Squamous Cell Carcinoma of the Esophagus

While surgery plays a major role in the treatment and potential cure of esophageal cancers, esophagectomy remains a high-risk operation with significant perioperative morbidity and mortality compared to other oncosurgical procedures. Perioperative management for esophagectomy is complex, and close attention to detail in various areas of anesthetic and perioperative management is crucial to improve postoperative outcomes. Patients undergoing esophagectomy should be offered an evidence-based risk assessment for their postoperative outcomes to allow active participation and informed, shared-decision making. Novel perioperative risk scores have been developed to predict both short-term and long-term outcomes in patients with esophageal cancer, although independent validation of such scoring systems is still required. Apart from accurate preoperative risk assessment, further efforts to improve morbidity and mortality from esophagectomy is achieved through comprehensive Enhanced Recovery after Surgery (ERAS) protocols, which comprise an individualized bundle of care throughout the perioperative journey for each patient and should be implemented as a standard practice. Furthermore, anesthetic practice and perioperative anesthetic drug usage can potentially affect cancer progression and recurrence. This chapter reviews current evidence for various factors that contribute to the improvement of perioperative outcomes, including prehabilitation, preoperative optimization of anemia, thoracic epidural analgesia, intraoperative protective ventilatory strategies, goal-directed fluid therapy, as well as special attention to other perioperative issues that potentially reduce anastomotic and cardiopulmonary complications. In summary, it is difficult to show a measurable benefit from any one single intervention, and a multidisciplinary approach that encompasses multiple aspects of perioperative care is necessary to improve outcomes after esophagectomy.

Local Anesthetics and Recurrence after Cancer Surgery-What's New? A Narrative Review

The perioperative use of regional anesthesia and local anesthetics is part of almost every anesthesiologist’s daily clinical practice. Retrospective analyses and results from experimental studies pointed towards a potential beneficial effect of the local anesthetics regarding outcome—i.e., overall and/or recurrence-free survival—in patients undergoing cancer surgery. The perioperative period, where the anesthesiologist is responsible for the patients, might be crucial for the further course of the disease, as circulating tumor cells (shed from the primary tumor into the patient’s bloodstream) might form new micro-metastases independent of complete tumor removal. Due to their strong anti-inflammatory properties, local anesthetics might have a certain impact on these circulating tumor cells, either via direct or indirect measures, for example via blunting the inflammatory stress response as induced by the surgical stimulus. This narrative review highlights the foundation of these principles, features recent experimental and clinical data and provides an outlook regarding current and potential future research activities.

Anaesthetic modality and post-surgical oncological outcomes for paediatric tumours: is there a link?

INTRODUCTION

Children with solid organ tumours often present for curative surgery. Even with the best surgical technique, micrometastases can occur. Preclinical studies support the postulation that neuraxial anaesthesia maintains the body's immune and inflammatory milieu against metastasis. However, human retrospective adult studies showed varying results, and no study has been done in children. We aimed to find out if intraoperative epidural, perioperative opioid and volatile dose are associated with relapse-free survival (RFS) in children with solid organ tumours.

METHODS

This is a retrospective cohort study of 126 children from a tertiary paediatric unit who were diagnosed with solid organ tumours (neuroblastoma, hepatoblastoma or sarcoma) over a 16-year period. RFS, stratified by tumour subtypes, was estimated using the Kaplan-Meier method. Adjusted hazard ratios (aHRs) were obtained from multivariable Cox regression models after taking potential covariates into account.

RESULTS

Of 126 children with solid organ tumours (51.6% neuroblastoma, 34.9% sarcoma and 13.5% hepatoblastoma), 53.2% received combined general anaesthesia (GA)/epidural. A total of 21 (31.3%) and 20 (33.9%) patients relapsed during the study period in the combined GA/epidural group and the GA alone group, respectively. Patients with sarcoma receiving combined GA/epidural had a clinically meaningful lower risk of relapse compared to patients receiving GA alone (aHR 0.51, 95% confidence interval 0.14-1.79), although this was not statistically significant.

CONCLUSION

Our study demonstrated some clinically meaningful associations, especially in paediatric sarcoma patients. Overall, however, there was no statistically significant association between epidural use and an improved RFS.

Impact of anesthesia methods on perioperative systemic inflammation and long-term outcomes in patients undergoing surgery for hepatocellular carcinoma: a propensity score-matched analysis

Background

Recent studies have shown regional anesthesia might improve the survival of cancer patients. We hypothesized that general-epidural anesthesia (GEA) was associated with longer survival than general anesthesia (GA) in patients undergoing hepatocellular carcinoma (HCC) resections.

Methods

A retrospective study included patients who received curative resection for HCC between January 2014 to December 2017. Patients were grouped in GEA vs. GA. After propensity score matching, perioperative inflammatory scores were calculated. Grade of postoperative complications, length of stay (LOS), dosage of sufentanil used and times of patients requiring rescue analgesia in both groups were compared for intraoperative and postoperative parameter. Survival curves were constructed from the date of surgery to death, univariable and multivariable Cox regression models were used to compare hazard ratios for death.

Results

A total of 772 patients were included in the study. With 386 patients in GA group and 386 patients in GEA group. After propensity score matching, the demographic and baseline biomarkers in the two groups were similar. Patients in GEA group showed significantly lower inflammatory scores. Grade of postoperative complications, LOS, opioid use, and times of patients requiring rescue analgesia was significantly lower in the GEA group. The overall survival (OS) and disease-free survival (DFS) rate was significantly lower in the GA group (54.2% vs. 62.3%, 41.2% vs. 52.5%, P<0.001). The multivariate analysis indicated the GA was associated with shorter OS (HR: 1.28, 95% CI: 1.07–2.02, P<0.001) and DFS (HR: 1.06, 95% CI: 1.03–1.71, P<0.001).

Conclusions

GA combined with epidural anesthesia is associated with lower levels of inflammation, and longer survival in patients undergoing hepatectomy.

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

Background

The aim of this study was to test the hypothesis that the use of inhalational anesthesia leads to higher suppression of the cell-mediated immunity compared to total intravenous anesthesia in patients undergoing kidney cancer surgery under combined low thoracic epidural analgesia and general anesthesia.

Methods

Patients were randomly allocated to either propofol-based (intravenous anesthetic) or sevoflurane-based (volatile anesthetic) anesthesia group with 10 patients in each group, along with epidural analgesia in both groups. Amounts of natural killer (NK) cells, total T lymphocytes, and T lymphocyte subpopulations in the blood samples collected from the patients before surgery, at the end of the surgery and postoperative days 1, 3 and 7 were determined by flow cytometric analysis. The NK cell count served as the primary endpoint of the study, whereas the total T lymphocyte count and cell counts for T lymphocyte subpopulations were used as the secondary endpoint.

Results

Our study showed that there were no significant differences in the amount of NK cells, total T lymphocytes, regulatory T cells, and T-helper cells, cytotoxic T lymphocytes, and their subpopulations between the propofol- and sevoflurane-based anesthesia groups when the anesthesia was administered in combination with epidural analgesia.

Conclusions

The results of this pilot study did not support the hypothesis that the use of inhalational anesthesia leads to higher suppression of the cell-mediated immunity than that of total intravenous anesthesia in patients undergoing kidney cancer surgery under combined low thoracic epidural analgesia and general anesthesia.

Impact of Anesthetics, Analgesics, and Perioperative Blood Transfusion in Pediatric Cancer Patients: A Comprehensive Review of the Literature

Cancer is the leading cause of death by disease in developed countries. Children and adolescents with cancer need surgical interventions (ie, biopsy or major surgery) to diagnose, treat, or palliate their malignancies. Surgery is a period of high vulnerability because it stimulates the release of inflammatory mediators, catecholamines, and angiogenesis activators, which coincides with a period of immunosuppression. Thus, during and after surgery, dormant tumors or micrometastasis (ie, minimal residual disease) can grow and become clinically relevant metastasis. Anesthetics (ie, volatile agents, dexmedetomidine, and ketamine) and analgesics (ie, opioids) may also contribute to the growth of minimal residual disease or disease progression. For instance, volatile anesthetics have been implicated in immunosuppression and direct stimulation of cancer cell survival and proliferation. Contrarily, propofol has shown in vitro anticancer effects. In addition, perioperative blood transfusions are not uncommon in children undergoing cancer surgery. In adults, an association between perioperative blood transfusions and cancer progression has been described for some malignancies. Transfusion-related immunomodulation is one of the mechanisms by which blood transfusions can promote cancer progression. Other mechanisms include inflammation and the infusion of growth factors. In the present review, we discuss different aspects of tumorigenesis, metastasis, angiogenesis, the immune system, and the current studies about the impact of anesthetics, analgesics, and perioperative blood transfusions on pediatric cancer progression.

Recurrence of breast cancer after regional or general anaesthesia: a randomised controlled trial

BACKGROUND

Three perioperative factors impair host defence against recurrence during cancer surgery: the surgical stress response, use of volatile anaesthetic, and opioids for analgesia. All factors are ameliorated by regional anaesthesia-analgesia. We tested the primary hypothesis that breast cancer recurrence after potentially curative surgery is lower with regional anaesthesia-analgesia using paravertebral blocks and the anaesthetic propofol than with general anaesthesia with the volatile anaesthetic sevoflurane and opioid analgesia. A second hypothesis was that regional anaesthesia-analgesia reduces persistent incisional pain.

METHODS

We did a randomised controlled trial at 13 hospitals in Argentina, Austria, China, Germany, Ireland, New Zealand, Singapore, and the USA. Women (age <85 years) having potentially curative primary breast cancer resections were randomised by computer to either regional anaesthesia-analgesia (paravertebral blocks and propofol) or general anaesthesia (sevoflurane) and opioid analgesia. The primary outcome was local or metastatic breast cancer recurrence. The secondary outcome was incisional pain at 6 months and 12 months. Primary analyses were done under intention-to-treat principles. This trial is registered with ClinicalTrials.gov, NCT00418457. The study was stopped after a preplanned futility boundary was crossed.

FINDINGS

Between Jan 30, 2007, and Jan 18, 2018, 2132 women were enrolled to the study, of whom 24 were excluded before surgery. 1043 were assigned to regional anaesthesia-analgesia and 1065 were allocated to general anaesthesia. Baseline characteristics were well balanced between study groups. Median follow-up was 36 (IQR 24-49) months. Among women assigned regional anaesthesia-analgesia, 102 (10%) recurrences were reported, compared with 111 (10%) recurrences among those allocated general anaesthesia (hazard ratio 0·97, 95% CI 0·74-1·28; p=0·84). Incisional pain was reported by 442 (52%) of 856 patients assigned to regional anaesthesia-analgesia and 456 (52%) of 872 patients allocated to general anaesthesia at 6 months, and by 239 (28%) of 854 patients and 232 (27%) of 852 patients, respectively, at 12 months (overall interim-adjusted odds ratio 1·00, 95% CI 0·85-1·17; p=0·99). Neuropathic breast pain did not differ by anaesthetic technique and was reported by 87 (10%) of 859 patients assigned to regional anaesthesia-analgesia and 89 (10%) of 870 patients allocated to general anaesthesia at 6 months, and by 57 (7%) of 857 patients and 57 (7%) of 854 patients, respectively, at 12 months.

INTERPRETATION

In our study population, regional anaesthesia-analgesia (paravertebral block and propofol) did not reduce breast cancer recurrence after potentially curative surgery compared with volatile anaesthesia (sevoflurane) and opioids. The frequency and severity of persistent incisional breast pain was unaffected by anaesthetic technique. Clinicians can use regional or general anaesthesia with respect to breast cancer recurrence and persistent incisional pain.

FUNDING

Sisk Healthcare Foundation (Ireland), Eccles Breast Cancer Research Fund, British Journal of Anaesthesia International, College of Anaesthetists of Ireland, Peking Union Medical College Hospital, Science Fund for Junior Faculty 2016, Central Bank of Austria, and National Healthcare Group.

Biomarkers for Evaluating the Inflammation Status in Patients with Cancer

Inflammation can be a causative factor for carcinogenesis or can result from a consequence of cancer progression. Moreover, cancer therapeutic interventions can also induce an inflammatory response. Various inflammatory parameters are used to assess the inflammatory status during cancer treatment. It is important to select the most optimal biomarker among these parameters. Additionally, suitable biomarkers must be examined if there are no known parameters. We briefly reviewed the published literature for the use of inflammatory parameters in the treatment of patients with cancer. Most studies on inflammation evaluated the correlation between host characteristics, effect of interventions, and clinical outcomes. Additionally, the levels of C-reactive protein, albumin, lymphocytes, and platelets were the most commonly used laboratory parameters, either independently or in combination with other laboratory parameters and clinical characteristics. Furthermore, the immune parameters are classically examined using flow cytometry, immunohistochemical staining, and enzyme-linked immunosorbent assay techniques. However, gene expression profiling can aid in assessing the overall peri-interventional immune status. The checklists of guidelines, such as STAndards for Reporting of Diagnostic accuracy and REporting recommendations for tumor MARKer prognostic studies should be considered when designing studies to investigate the inflammatory parameters. Finally, the data should be interpreted after adjusting for clinically important variables, such as age and cancer stage.

Influence of perioperative anaesthetic and analgesic interventions on oncological outcomes: a narrative review

Surgery is an important treatment modality for the majority of solid organ cancers. Unfortunately, cancer recurrence following surgery of curative intent is common, and typically results in refractory disease and patient death. Surgery and other perioperative interventions induce a biological state conducive to the survival and growth of residual cancer cells released from the primary tumour intraoperatively, which may influence the risk of a subsequent metastatic disease. Evidence is accumulating that anaesthetic and analgesic interventions could affect many of these pathophysiological processes, influencing risk of cancer recurrence in either a beneficial or detrimental way. Much of this evidence is from experimental in vitro and in vivo models, with clinical evidence largely limited to retrospective observational studies or post hoc analysis of RCTs originally designed to evaluate non-cancer outcomes. This narrative review summarises the current state of evidence regarding the potential effect of perioperative anaesthetic and analgesic interventions on cancer biology and clinical outcomes. Proving a causal link will require data from prospective RCTs with oncological outcomes as primary endpoints, a number of which will report in the coming years. Until then, there is insufficient evidence to recommend any particular anaesthetic or analgesic technique for patients undergoing tumour resection surgery on the basis that it might alter the risk of recurrence or metastasis.

Comparison between the effect of epidural anesthesia combined with epidural analgesia and general anesthesia combined with intravenous analgesia on prognosis of ovarian cancer patients

Application value of epidural anesthesia combined with epidural analgesia and general anesthesia combined with intravenous analgesia in ovarian cancer surgery was explored. In total 298 ASA I–III grade patients with ovarian cancer, undergoing extensive total hysterectomy and pelvic lymphotomy, were retrospectively analyzed. Patients were divided into two groups: the epidural anesthesia combined with epidural analgesia group (group A, 158 cases), and the general anesthesia combined with intravenous analgesia group (group B, 140 cases). The first exhaust time, incidence of adverse reactions, Aldrete score, and recovery were observed, and the visual analogue scale (VAS) scores during resting, exercise and cough at 24 h after surgery were recorded. Fasting venous blood (2 ml) was drawn at the same time before anesthesia and at 24 h after anesthesia in both groups to determinate cortisol (COR) and C-reactive protein (CRP) levels. The first exhaust time and incidence of adverse reactions in group A were significantly lower than those in group B (P<0.05). The Aldrete score and extubation time (ET) in group A were significantly higher than that in group B. Eye opening time (EOT), recovery orientation time (ROT) and post-anesthesia care unit (PACU) time in group A were significantly lower than those in group B (P<0.05). The VAS scores in group A during resting, exercise and cough were lower than those in group B (P<0.05). Compared with before anesthesia, the levels of COR and CRP increased significantly in both groups at 24 h after anesthesia (P<0.05), while the level of COR and CRP in group A was significantly lower than that in group B, at 24 h after surgery (P<0.05). Epidural anesthesia combined with epidural analgesia has better analgesic effect, higher safety, lower incidence of adverse reactions, and is beneficial to the recovery of patients with ovarian cancer after radical operation when compared with general anesthesia combined with intravenous analgesia.

Surgical approach and the impact of epidural analgesia on survival after esophagectomy for cancer: A population-based retrospective cohort study

BACKGROUND

Esophagectomy for esophageal cancer carries high morbidity and mortality, particularly in older patients. Transthoracic esophagectomy allows formal lymphadenectomy, but leads to greater perioperative morbidity and pain than transhiatal esophagectomy. Epidural analgesia may attenuate the stress response and be less immunosuppressive than opioids, potentially affecting long-term outcomes. These potential benefits may be more pronounced for transthoracic esophagectomy due to its greater physiologic impact. We evaluated the impact of epidural analgesia on survival and recurrence after transthoracic versus transhiatal esophagectomy.

METHODS

A retrospective cohort study was performed using the linked Surveillance, Epidemiology and End Results (SEER)-Medicare database. Patients aged ≥66 years with locoregional esophageal cancer diagnosed 1994-2009 who underwent esophagectomy were identified, with follow-up through December 31, 2013. Epidural receipt and surgical approach were identified from Medicare claims. Survival analyses adjusting for hospital esophagectomy volume, surgical approach, and epidural use were performed. A subgroup analysis restricted to esophageal adenocarcinoma patients was performed.

RESULTS

Among 1,921 patients, 38% underwent transhiatal esophagectomy (n = 730) and 62% underwent transthoracic esophagectomy (n = 1,191). 61% (n = 1,169) received epidurals and 39% (n = 752) did not. Epidural analgesia was associated with transthoracic approach and higher volume hospitals. Patients with epidural analgesia had better 90-day survival. Five-year survival was higher with transhiatal esophagectomy (37.2%) than transthoracic esophagectomy (31.0%, p = 0.006). Among transthoracic esophagectomy patients, epidural analgesia was associated with improved 5-year survival (33.5% epidural versus 26.5% non-epidural, p = 0.012; hazard ratio 0.81, 95% confidence interval [0.70, 0.93]). Among the subgroup of esophageal adenocarcinoma patients undergoing transthoracic esophagectomy, epidural analgesia remained associated with improved 5-year survival (hazard ratio 0.81, 95% confidence interval [0.67, 0.96]); this survival benefit persisted in sensitivity analyses adjusting for propensity to receive an epidural.

CONCLUSION

Among patients undergoing transthoracic esophagectomy, including a subgroup restricted to esophageal adenocarcinoma, epidural analgesia was associated with improved survival even after adjusting for other factors.

Perioperative epidural use and survival outcomes in patients undergoing primary debulking surgery for advanced ovarian cancer

OBJECTIVE

Epidurals are associated with improved outcomes in some solid tumors, presumably due to their effect on surgical stress response. There are limited data on the prognostic significance of epidural anesthesia in patients undergoing primary debulking surgery (PDS) for advanced ovarian cancer. We sought to assess the impact of epidural anesthesia on the survival outcomes of patients undergoing PDS for advanced ovarian cancer.

METHODS

In this retrospective study, consecutive patients with stage IIIB-IV epithelial ovarian, fallopian tube, or peritoneal carcinoma who underwent PDS at our institution from 01/2005-12/2013 were identified. Progression-free survival (PFS) and overall survival (OS) with regard to epidural use were analyzed.

RESULTS

Of 648 patients, 435 received an epidural and 213 did not. Patients in the former group were more likely to have higher stage disease (stage IV disease, 26% vs. 16%, respectively; P = .005), carcinomatosis (87% vs. 80%, respectively; P = .027), and bulky upper abdominal disease (66% vs. 58%, respectively; P = .046). Complete gross resection was achieved in 48% and 32%, respectively (P < .001). For the epidural vs. non-epidural groups, median PFS was 20.8 months and 13.9 months, respectively (P = .021); median OS was 62.4 months and 41.9 months, respectively (P < .001). After controlling for confounding factors, including residual disease, epidural use was independently associated with a decreased risk of progression (HR = 1.327; 95% CI, 1.066-1.653) and death (HR = 1.588; 95% CI, 1.224-2.06).

CONCLUSIONS

Perioperative epidural use was independently associated with improved PFS and OS in these patients. Epidural anesthesia at the time of PDS may be warranted in this setting.

Regional anesthesia and analgesia in cancer care: is it time to break the bad news?

PURPOSE OF REVIEW

There is ongoing controversy regarding the tumor-protective effects of regional anesthesia in patients undergoing cancer surgery. Evidence of up-to-date systematic reviews will be presented alongside recent updates on the effects of opioids and local anesthetics.

RECENT FINDINGS

In recent years, the literature regarding the effects of regional anesthesia techniques on cancer recurrence has raised many unanswered questions. Ongoing randomized controlled trials may not be able to shed light on the controversial discussion regarding the tumor protective effects of regional anesthesia because the expected effect size and event rate in those studies may be overstated.Recent more refined animal data, provides no evidence to suggest that opioids promote cancer recurrence or facilitate the development of metastatic disease.In addition, local anesthetics have promising preclinical anticarcinogenic effects that extend beyond their voltage-gated sodium channel blocking properties and could be of therapeutic value.

SUMMARY

Cancer recurrence in patients undergoing surgery remains a global burden. Current evidence suggests that regional techniques, opioid analgesia and local anesthetics in onco-anesthesia may require a tailored individual approach due to the phenotypic and genotypic heterogeneity within and between different tumors. The authors surmise that future or ongoing randomized controlled trials regarding regional anesthesia techniques and cancer outcome may not be able to reproduce clear results, as it will be challenging to prove the efficacy of one single intervention (e.g. regional anesthesia) in an otherwise complex multifactorial perioperative oncological setting.

Perioperative events influence cancer recurrence risk after surgery

Surgery is a mainstay treatment for patients with solid tumours. However, despite surgical resection with a curative intent and numerous advances in the effectiveness of (neo)adjuvant therapies, metastatic disease remains common and carries a high risk of mortality. The biological perturbations that accompany the surgical stress response and the pharmacological effects of anaesthetic drugs, paradoxically, might also promote disease recurrence or the progression of metastatic disease. When cancer cells persist after surgery, either locally or at undiagnosed distant sites, neuroendocrine, immune, and metabolic pathways activated in response to surgery and/or anaesthesia might promote their survival and proliferation. A consequence of this effect is that minimal residual disease might then escape equilibrium and progress to metastatic disease. Herein, we discuss the most promising proposals for the refinement of perioperative care that might address these challenges. We outline the rationale and early evidence for the adaptation of anaesthetic techniques and the strategic use of anti-adrenergic, anti-inflammatory, and/or antithrombotic therapies. Many of these strategies are currently under evaluation in large-cohort trials and hold promise as affordable, readily available interventions that will improve the postoperative recurrence-free survival of patients with cancer.

The Amide Local Anesthetic Lidocaine in Cancer Surgery-Potential Antimetastatic Effects and Preservation of Immune Cell Function? A Narrative Review

Surgical removal of the primary tumor in solid cancer is an essential component of the treatment. However, the perioperative period can paradoxically lead to an increased risk of cancer recurrence. A bimodal dynamics for early-stage breast cancer recurrence suggests a tumor dormancy-based model with a mastectomy-driven acceleration of the metastatic process and a crucial role of the immunosuppressive state during the perioperative period. Recent evidence suggests that anesthesia could also influence the progress of the disease. Local anesthetics (LAs) have long been used for their properties to block nociceptive input. They also exert anti-inflammatory capacities by modulating the liberation or signal propagation of inflammatory mediators. Interestingly, LAs can reduce viability and proliferation of many cancer cells in vitro as well. Additionally, retrospective clinical trials have suggested that regional anesthesia for cancer surgery (either with or without general anesthesia) might reduce the risk of recurrence. Lidocaine, a LA, which can be administered intravenously, is widely used in clinical practice for multimodal analgesia. It is associated with a morphine-sparing effect, reduced pain scores, and in major surgery probably also with a reduced incidence of postoperative ileus and length of hospital stay. Systemic delivery might therefore be efficient to target residual disease or reach cells able to form micrometastasis. Moreover, an in vitro study has shown that lidocaine could enhance the activity of natural killer (NK) cells. Due to their ability to recognize and kill tumor cells without the requirement of prior antigen exposure, NKs are the main actor of the innate immune system. However, several perioperative factors can reduce NK activity, such as stress, pain, opioids, or general anesthetics. Intravenous lidocaine as part of the perioperative anesthesia regimen would be of major interest for clinicians, as it might bear the potential to reduce the risk of cancer recurrence or progression patients undergoing cancer surgery. As a well-known pharmaceutical agent, lidocaine might therefore be a promising candidate for oncological drug repurposing. We urgently need clinical randomized trials assessing the protective effect of lidocaine on NKs function and against recurrence after cancer surgery to achieve a “proof of concept.”

Anesthetic technique and cancer recurrence in oncologic surgery: unraveling the puzzle

Surgery/anesthetic technique-stimulated immunosuppression in the perioperative period might cause an increase in cancer-related mortality. Whether anesthetic technique can affect the outcomes of cancer patients remains inconclusive. This review discusses data from the available literature on anesthetic techniques applied in oncologic surgery, the long-term outcomes of anesthetic technique, and their relation to survival and cancer recurrence. Searches of the PubMed database up to June 30, 2016, were conducted to identify publications with the terms "anesthetic technique and cancer recurrence," "regional anesthesia and cancer recurrence," "local anesthesia and cancer recurrence," "anesthetic technique and immunosuppression," and "anesthetic technique and oncologic surgery." Surgery/anesthesia-stimulated activation of the hypothalamic-pituitary-adrenal (HPA) axis and the sympathetic nervous system (SNS) provides immunosuppression through several soluble factors. Volatile anesthetics and opioids suppress cell-mediated immunity (CMI) and promote the proliferation of cancer cells and angiogenesis, whereas propofol does not suppress CMI and inhibits tumor angiogenesis. Regional anesthesia (RA) protects CMI and diminishes the surgical neuroendocrine stress response by blocking afferent neural transmission that stimulates the HPA axis and SNS, decreasing the requirement for opioids and volatile anesthetics and thereby decreasing cancer recurrence. Preclinical and retrospective studies highlight a potential benefit of anesthetic technique in reducing cancer-related mortality and recurrence by attenuating immunosuppression following surgical treatment in patients with specific types of cancer. Several well-planned, prospective, randomized controlled trials (RCTs) are underway that may provide more conclusive and definitive results regarding the benefits of anesthetic technique on survival in oncologic surgery.

Perioperative Anesthesia Care and Tumor Progression

This narrative review discusses the most recent up-to-date findings focused on the currently available "best clinical practice" regarding perioperative anesthesia care bundle factors and their effect on tumor progression. The main objective is to critically appraise the current literature on local anesthetics, regional outcome studies, opioids, and nonsteroidal anti-inflammatory drugs (NSAIDs) and their ability to decrease recurrence in patients undergoing cancer surgery. A brief discussion of additional topical perioperative factors relevant to the anesthesiologist including volatile and intravenous anesthetics, perioperative stress and anxiety, nutrition, and immune stimulation is included. The results of several recently published systematic reviews looking at the association between cancer recurrences and regional anesthesia have yielded inconclusive data and provide insufficient evidence regarding a definitive benefit of regional anesthesia. Basic science data suggests an anti tumor effect induced by local anesthetics. New refined animal models show that opioids can safely be used for perioperative pain management. Preliminary evidence suggests that NSAIDs should be an essential part of multimodal analgesia. Volatile anesthetics have been shown to increase tumor formation, whereas preclinical and emerging clinical data from propofol indicate tumor protective qualities. The perioperative period in the cancer patient represents a unique environment where surgically mediated stress response leads to immune suppression. Regional anesthesia techniques when indicated in combination with multimodal analgesia that include NSAIDs, opioids, and local anesthetics to prevent the pathophysiologic effects of pain and neuroendocrine stress response should be viewed as an essential part of balanced anesthesia.

Influence of opioids on immune function in patients with cancer pain: from bench to bedside

In patients with cancer, opioids are principally used for the management of acute surgical and chronic cancer-related pain. However, opioids have many non-analgesic effects, including direct and indirect effects on cancer cells and on anti-tumour immunity (NK cells, macrophages and T-cells). Direct effects on immune cells are manifested via opioid and non-opioid toll-like receptors, whereas indirect effects are manifested via the sympathetic nervous system and hypothalamic-pituitary-adrenal axis. Opioids can also decrease/alter immune cell infiltration into the tumour micro-environment. Animal models have shown that this is not a class effect, in that morphine and fentanyl suppress NK cell cytotoxicity; buprenorphine does not affect NK cell cytotoxicity, whereas tramadol increases NK cell cytotoxicity, reducing metastasis. In healthy individuals, morphine suppresses and fentanyl enhances NK cell cytotoxicity. In patients undergoing surgery, fentanyl decreased and tramadol increased NK cell cytotoxicity; clinical outcomes were not determined. Meta-analyses of opioid-sparing surgical studies report an association between improved recurrence-free and/or overall survival with regional/neuraxial anaesthesia compared with systemic opioids. In patients receiving opioids for non-surgical cancer-related pain, morphine has variable effects on immunity; clinical outcomes were not assessed. Although there is a potential association between systemic opioid administration and shorter survival in cancer patients with a prognosis of months to years, studies have not been designed to primarily assess survival, as a consequence of which causality cannot be apportioned. Pain is immunosuppressive, so analgesia is important. Opioids for cancer-related pain will continue to be recommended until definitive data on the effects of opioids on clinical outcomes in specific patient groups becomes available.

LINKED ARTICLES

This article is part of a themed section on Emerging Areas of Opioid Pharmacology. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v175.14/issuetoc.