Cancer recurrence after surgery: Direct and indirect effects of anesthetic agents*

Anesthesia for the child with cancer

Children with cancer undergo a host of surgeries and procedures that require anesthesia during the various phases of the disease. A safe anesthetic plan includes consideration of the direct effects of tumor, toxic effects of chemotherapy and radiation therapy, the specifics of the surgical procedure, drug-drug interactions with chemotherapy agents, pain syndromes, and psychological status of the child. This article provides a comprehensive overview of the anesthetic management of the child with cancer, focuses on a systems-based approach to the impact from both tumor and its treatment in children, and presents a discussion of the relevant anesthetic considerations.

Ultrasound-guided Multilevel Paravertebral Blocks and Total Intravenous Anesthesia Improve the Quality of Recovery after Ambulatory Breast Tumor Resection

Background:

Regional anesthesia improves postoperative analgesia and enhances quality of recovery (QoR) after ambulatory surgery. This randomized, double-blinded, parallel-group, placebo-controlled trial examines the effects of multilevel ultrasound-guided paravertebral blocks (PVBs) and total intravenous anesthesia on QoR after ambulatory breast tumor resection.

Methods:

Sixty-six women were randomized to standardized general anesthesia (control group) or PVBs and propofol-based total intravenous anesthesia (PVB group). The PVB group received T1–T5 PVBs with 5 ml of 0.5% ropivacaine per level, whereas the control group received sham subcutaneous injections. Postoperative QoR was designated as the primary outcome. The 29-item ambulatory QoR tool was administered in the preadmission clinic, before discharge, and on postoperative days 2, 4, and 7. Secondary outcomes included block success, pain scores, intra- and postoperative morphine consumption, time to rescue analgesia, incidence of nausea and vomiting, and hospital discharge time.

Results:

Data from sixty-four patients were analyzed. The PVB group had higher QoR scores than control group upon discharge (146 vs. 131; P < 0.0001) and on postoperative day 2 (145 vs. 135; P = 0.013); improvements beyond postoperative day 2 lacked statistical significance. None of the PVB group patients required conversion to inhalation gas–based general anesthesia or experienced block-related complications. PVB group patients had improved pain scores on postanesthesia care unit admission and discharge, hospital discharge, and postoperative day 2; their intraoperative morphine consumption, incidence of nausea and vomiting, and discharge time were also reduced.

Conclusion:

Combining multilevel PVBs with total intravenous anesthesia provides reliable anesthesia, improves postoperative analgesia, enhances QoR, and expedites discharge compared with inhalational gas- and opioid-based general anesthesia for ambulatory breast tumor resection.

Anesthetic techniques and cancer recurrence after surgery

Many of the most common anesthetics are used in surgical oncology, yet effects on cancer cells are still not known. Anesthesia technique could differentially affect cancer recurrence in oncologic patients undergoing surgery, due to immunosuppression, stimulation of angiogenesis, and dissemination of residual cancer cells. Data support the use of intravenous anesthetics, such as propofol anesthesia, thanks to antitumoral protective effects inhibiting cyclooxygenase 2 and prostaglandins E2 in cancer cells, and stimulation of immunity response; a restriction in the use of volatile anesthetics; restriction in the use of opioids as they suppress humoral and cellular immunity, and their chronic use favors angiogenesis and development of metastases; use of locoregional anesthesia compared with general anesthesia, as locoregional appears to reduce cancer recurrence after surgery. However, these findings must be interpreted cautiously as there is no evidence that simple changes in the practice of anesthesia can have a positive impact on postsurgical survival of cancer patients.

Isoflurane, a commonly used volatile anesthetic, enhances renal cancer growth and malignant potential via the hypoxia-inducible factor cellular signaling pathway in vitro

BACKGROUND

Growing evidence indicates that perioperative factors, including choice of anesthetic, affect cancer recurrence after surgery although little is known about the effect of anesthetics on cancer cells themselves. Certain anesthetics are known to affect hypoxia cell signaling mechanisms in healthy cells by up-regulating hypoxia-inducible factors (HIFs). HIFs are also heavily implicated in tumorigenesis and high levels correlate with poor prognosis.

METHODS

Renal cell carcinoma (RCC4) cells were exposed to isoflurane for 2 h at various concentrations (0.5-2%). HIF-1α, HIF-2α, phospho-Akt, and vascular endothelial growth factor A levels were measured by immunoblotting at various time points (0-24 h). Cell migration was measured across various components of extracellular matrix, and immunocytochemistry was used to analyze proliferation rate and cytoskeletal changes.

RESULTS

Isoflurane up-regulated levels of HIF-1α and HIF-2α and intensified expression of vascular endothelial growth factor A. Exposed cultures contained significantly more cells (1.81 ± 0.25 vs. 1.00 of control; P = 0.03) and actively proliferating cells (89.4 ± 2.80 vs. 64.74 ± 7.09% of control; P = 0.016) than controls. These effects were abrogated when cells were pretreated with the Akt inhibitor, LY294002. Exposed cells also exhibited greater migration on tissue culture-coated (F = 16.89; P = 0.0008), collagen-coated (F = 20.99; P = 0.0003), and fibronectin-coated wells (F = 8.21; P = 0.011) as along with dramatic cytoskeletal rearrangement, with changes to both filamentous actin and α-tubulin.

CONCLUSIONS

These results provide evidence that a frequently used anesthetic can exert a protumorigenic effect on a human cancer cell line. This may represent an important contributory factor to high recurrence rates observed after surgery.

Regional anaesthesia and cancer metastases: the implication of local anaesthetics

Clinical and basic science studies have demonstrated the anti-inflammatory properties of local anaesthetics. Recent studies have begun to unravel molecular pathways linking inflammation and cancer. Regional anaesthesia is associated in some retrospective clinical studies with reduced risk of metastasis and increased long-term survival. The potential beneficial effects of regional anaesthesia have been attributed mainly to the inhibition of the neuroendocrine stress response to surgery and to the reduction in the requirements of volatile anaesthetics and opioids. Because cancer is linked to inflammation and local anaesthetics have anti-inflammatory effects, these agents may participate in reducing the risk of metastasis, but their mechanism of action is unknown. We demonstrated in vitro that amide local anaesthetics attenuate tumour cell migration as well as signalling pathways enhancing tumour growth and metastasis. This has provided the first evidence of a molecular mechanism by which regional anaesthesia might inhibit or reduce cancer metastases.

Does regional anaesthesia and analgesia or opioid analgesia influence recurrence after primary cancer surgery? An update of available evidence

Cancer continues to be a key cause of morbidity and mortality worldwide and its overall incidence continues to increase. Anaesthetists are increasingly faced with the challenge of managing cancer patients, for surgical resection to debulk or excise the primary tumour, or for surgical emergencies in patients on chemotherapy or for the analgesic management of disease- or treatment-related chronic pain. Metastatic recurrence is a concern. Surgery and a number of perioperative factors are suspected to accelerate tumour growth and potentially increase the risk of metastatic recurrence. Retrospective analyses have suggested an association between anaesthetic technique and cancer outcomes, and anaesthetists have sought to ameliorate the consequences of surgical trauma and minimise the impact of anaesthetic interventions. Just how anaesthesia and analgesia impact cancer recurrence and consequent survival is very topical, as understanding the potential mechanisms and interactions has an impact on the anaesthetist's ability to contribute to the successful outcome of oncological interventions. The outcome of ongoing, prospective, randomized trials are awaited with interest.

Anaesthetic agents for thoracic surgery: what's best?

PURPOSE OF REVIEW

Pneumonectomy is still associated with a 5% 30-day mortality in a large series involving a variety of anaesthetic agents and techniques.

RECENT FINDINGS

As well as the immediate 'anaesthetic' complications of pain, nausea and vomiting and respiratory dysfunction, differences between anaesthetic agents have emerged in systemic inflammation, postoperative cognitive dysfunction, immune suppression and cell signalling after surgery.

SUMMARY

No one anaesthetic agent has emerged as best. There is a trade-off between initial success and long-term problems or vice versa.

Can anaesthetic and analgesic techniques affect cancer recurrence or metastasis?

Cancer is a leading cause of morbidity and mortality worldwide and the ratio of incidence is increasing. Mortality usually results from recurrence or metastases. Surgical removal of the primary tumour is the mainstay of treatment, but this is associated with inadvertent dispersal of neoplastic cells into the blood and lymphatic systems. The fate of the dispersed cells depends on the balance of perioperative factors promoting tumour survival and growth (including surgery per se, many anaesthetics per se, acute postoperative pain, and opioid analgesics) together with the perioperative immune status of the patient. Available evidence from experimental cell culture and live animal data on these factors are summarized, together with clinical evidence from retrospective studies. Taken together, current data are sufficient only to generate a hypothesis that an anaesthetic technique during primary cancer surgery could affect recurrence or metastases, but a causal link can only be proved by prospective, randomized, clinical trials. Many are ongoing, but definitive results might not emerge for a further 5 yr or longer. Meanwhile, there is no hard evidence to support altering anaesthetic technique in cancer patients, pending the outcome of the ongoing clinical trials.

Surgery and stress promote cancer metastasis: new outlooks on perioperative mediating mechanisms and immune involvement

Surgery for the removal of a primary tumor presents an opportunity to eradicate cancer or arrest its progression, but is also believed to promote the outbreak of pre-existing micrometastases and the initiation of new metastases. These deleterious effects of surgery are mediated through various mechanisms, including psychological and physiological neuroendocrine and paracrine stress responses elicited by surgery. In this review we (i) describe the many risk factors that arise during the perioperative period, acting synergistically to make this short timeframe critical for determining long-term cancer recurrence, (ii) present newly identified potent immunocyte populations that can destroy autologous tumor cells that were traditionally considered immune-resistant, thus invigorating the notion of immune-surveillance against cancer metastasis, (iii) describe in vivo evidence in cancer patients that support a role for anti-cancer immunity, (iv) indicate neuroendocrine and paracrine mediating mechanisms of stress- and surgery-induced promotion of cancer progression, focusing on the prominent role of catecholamines and prostaglandins through their impact on anti-cancer immunity, and through direct effects on the malignant tissue and its surrounding, (v) discuss the impact of different anesthetic approaches and other intra-operative procedures on immunity and cancer progression, and (vi) suggest prophylactic measures against the immunosuppressive and cancer promoting effects of surgery.

The Effects of Epidural Anaesthesia and Analgesia on Natural Killer Cell Cytotoxicity and Cytokine Response in Patients with Epithelial Ovarian Cancer Undergoing Radical Resection

Objective:

Epidural anaesthesia appears to promote antitumourigenic activity in patients with malignant disease who are undergoing surgery. This study investigated immune function in women with epithelial ovarian cancer undergoing radical resection with either general anaesthesia alone or in combination with epidural anaesthesia.

Methods:

Patients ( n = 61) were randomized to receive either combined general/epidural anaesthesia (study group) or general anaesthesia alone (control group). Natural killer cell cytotoxicity (NKCC) and serum concentrations of four cytokines (interleukin [IL]-1β, -8 and -10 and interferon [IFN]-γ) were measured before anaesthesia ( Tpre) and 4h after skinincision ( T4 h) in both groups.

Results:

In both groups, concentrations of protumourigenic cytokines (IL-1β and IL-8) were significantly higher at T4 h than at Tpre, while concentrations of antitumourigenic cytokines (IL-10 and IFN-γ) and NKCC were significantly lower at T4 h. The study group had significantly higher NKCC, IL-10 and IFN-γ levels and lower IL-1β and IL-8 levels at TT h compared with the control group.

Conclusion:

Combined general/epidural anaesthesia appeared to promote antitumourigenic NKCC and cytokine responses.

Polymorphism of A118G in μ-opioid receptor gene is associated with risk of esophageal squamous cell carcinoma in a Chinese population

BACKGROUND

Previous studies have indicated a direct effect of μ-opioid receptors on tumor progression or recurrence. An A118G polymorphism in the μ-opioid receptor gene was believed to play an important role in this carcinogenic process. The aim of the present study was to investigate the association between the A118G polymorphism and the risk of esophageal squamous cell carcinoma (ESCC) in a Chinese population.

METHOD

The case-control study included 260 cancer patients and 291 controls from a Chinese Han and Chinese TuJia population in Enshi region, China. Genotypes were determined by TaqMan platform. Odds ratios (ORs) and 95 % confidence intervals (CIs) were calculated using multivariate unconditional logistic regression.

RESULTS

Compared with the G/G genotype, the A/A genotype exhibited a significantly elevated risk for ESCC (OR = 3.12, 95 % CI [1], 1.11-6.01). A significant interaction between the A118G polymorphism and age, smoking status, and family history of cancer was also found (OR = 2.25, 95 % CI 1.36-4.12; OR = 1.75, 95 % CI 1.23-2.32; OR = 3.14, 95 % CI 1.31-7.28, respectively).

CONCLUSION

The A118G polymorphism in the μ-opioid receptor gene might be associated with the risk of ESCC in Chinese population.