Combined neurolytic block of celiac, inferior mesenteric, and superior hypogastric plexuses for incapacitating abdominal and/or pelvic cancer pain

Sympathetic nerve blocks for persistent pain in adults with inoperable abdominopelvic cancer

BACKGROUND

Persistent visceral pain is an unpleasant sensation coming from one or more organs within the body. Visceral pain is a common symptom in those with advanced cancer. Interventional procedures, such as neurolytic sympathetic nerve blocks, have been suggested as additional treatments that may play a part in optimising pain management for individuals with this condition.

OBJECTIVES

To evaluate the benefits and harms of neurolytic sympathetic nerve blocks for persistent visceral pain in adults with inoperable abdominopelvic cancer compared to standard care or placebo and comparing single blocks to combination blocks.

SEARCH METHODS

We searched the following databases without language restrictions on 19 October 2022 and ran a top-up search on 31 October 2023: CENTRAL; MEDLINE via Ovid; Embase via Ovid; LILACS. We searched trial registers without language restrictions on 2 November 2022: ClinicalTrials.gov; WHO International Clinical Trials Registry Platform (ICTRP). We searched grey literature, checked reference lists of reviews and retrieved articles for additional studies, and performed citation searches on key articles. We also contacted experts in the field for unpublished and ongoing trials. Our trial protocol was preregistered in the Cochrane Database of Systematic Reviews on 21 October 2022.

SELECTION CRITERIA

We searched for randomised controlled trials (RCTs) comparing any sympathetic nerve block targeting sites commonly used to treat abdominal pelvic pain from inoperable malignancies in adults to standard care or placebo.

DATA COLLECTION AND ANALYSIS

We independently selected trials based on predefined inclusion criteria, resolving any differences via adjudication with a third review author. We used a random-effects model as some heterogeneity was expected between the studies due to differences in the interventions being assessed and malignancy types included in the study population. We chose three primary outcomes and four secondary outcomes of interest. We sought consumer input to refine our review outcomes and assessed extracted data using Cochrane's risk of bias 2 tool (RoB 2). We assessed the certainty of evidence using the GRADE system.

MAIN RESULTS

We included 17 studies with 1025 participants in this review. Fifteen studies with a total of 951 participants contributed to the quantitative analysis. Single block versus standard care Primary outcomes No included studies reported our primary outcome, 'Proportion of participants reporting no worse than mild pain after treatment at 14 days'. The evidence is very uncertain about the effect of sympathetic nerve blocks on reducing pain to no worse than mild pain at 14 days when compared to standard care due to insufficient data (very low-certainty evidence). Sympathetic nerve blocks may provide small to 'little to no' improvement in quality of life (QOL) scores at 14 days after treatment when compared to standard care, but the evidence is very uncertain (standardised mean difference (SMD) -0.73, 95% confidence interval (CI) -1.70 to 0.25; I² = 87%; 4 studies, 150 participants; very low-certainty evidence). The evidence is very uncertain about the risk of serious adverse events as defined in our review as only one study contributed data to this outcome. Sympathetic nerve blocks may have an 'increased risk' to 'no additional risk' of harm compared with standard care (very low-certainty evidence). Secondary outcomes Sympathetic nerve blocks showed a small to 'little to no' effect on participant-reported pain scores at 14 days using a 0 to 10 visual analogue scale (VAS) for pain compared with standard care, but the evidence is very uncertain (mean difference (MD) -0.44, 95% CI -0.98 to 0.11; I² = 56%; 5 studies, 214 participants; very low-certainty evidence). There may be a 'moderate to large' to 'little to no' reduction in daily consumption of opioids postprocedure at 14 days with sympathetic nerve blocks compared with standard care, but the evidence is very uncertain (change in daily consumption of opioids at 14 days as oral milligrams morphine equivalent (MME): MD -41.63 mg, 95% CI -78.54 mg to -4.72 mg; I² = 90%; 4 studies, 130 participants; very low-certainty evidence). The evidence is very uncertain about the effect of sympathetic nerve blocks on participant satisfaction with procedure at 0 to 7 days and time to need for retreatment or treatment effect failure (or both) due to insufficient data. Combination block versus single block Primary outcomes There is no evidence about the effect of combination sympathetic nerve blocks compared with single sympathetic nerve blocks on the proportion of participants reporting no worse than mild pain after treatment at 14 days because no studies reported this outcome. There may be a small to 'little to no' effect on QOL score at 14 days after treatment, but the evidence is very uncertain (very low-certainty evidence). The evidence is very uncertain about the risk of serious adverse events with combination sympathetic nerve blocks compared with single sympathetic nerve blocks due to limited reporting in the included studies (very low-certainty evidence). Secondary outcomes The evidence is very uncertain about the effect of combination sympathetic nerve blocks compared with single sympathetic nerve blocks on participant-reported pain score and change in daily consumption of opioids postprocedure, at 14 days. There may be a small to 'little to no' effect, but the evidence is very uncertain (very low-certainty evidence). There is no evidence about the effect on participant satisfaction with procedure at 0 to 7 days and time to need for retreatment or treatment effect failure (or both) due to these outcomes not being measured by the studies. Risk of bias The risk of bias was predominately high for most outcomes in most studies due to significant concerns regarding adequate blinding. Very few studies were deemed as low risk across all domains for any outcome.

AUTHORS' CONCLUSIONS

There is limited evidence to support or refute the use of sympathetic nerve blocks for persistent abdominopelvic pain due to inoperable malignancy. We are very uncertain about the effect of combination sympathetic nerve blocks compared with single sympathetic nerve blocks. The certainty of the evidence is very low and these findings should be interpreted with caution.

Inferior mesenteric plexus block under computed tomography guidance: A case report

RATIONALE

Inferior mesenteric plexus block is indicated for left-sided lower abdominal pain. However, in patients with terminal cancer, severe abdominal pain can prevent the patient from maintaining the necessary posture during the procedure, and considerable anatomic deformation owing to extensive growth, invasion, and metastasis of the tumor in the abdominal cavity can make the procedure difficult. In these cases, performing the procedures under computed tomography (CT) guidance can ensure greater safety and accuracy.

PATIENT CONCERNS

A 63-year-old man was referred for severe left-sided lower abdominal pain. He was unable to lie prone owing to severe lower abdominal pain and right hip surgery performed 15 years ago. His visual analog scale score was 9 out of 10.

DIAGNOSES

The patient had terminal pancreatic tail cancer. Compared with abdominal CT findings obtained 50 days ago, hepatic metastasis and peritoneal seeding were still present, infiltration to the tissues around the pancreas and retrogastric area was increased, and most of the abdominal aorta was encased. In addition, metastatic lymph nodes were identified in several areas on the left including the left para-aortic area. However, the lesion causing the pain could not be identified. Therefore, an inferior mesenteric plexus block was performed according to the patient's complaint.

INTERVENTIONS

Epidural patient-controlled analgesia was performed first. The patient's pain consequently reduced to a certain level, and the prone position became possible to some extent, so a CT-guided inferior mesenteric plexus block was performed 2 days later.

OUTCOMES

After the CT-guided inferior mesenteric plexus block, it became possible to control the patient's pain with a fentanyl patch 75 mcg/hour only, and his visual analog scale score was reduced to 4. After 4 weeks, the patient died without complaints of severe pain as before.

LESSONS

CT-guided inferior mesenteric plexus block can be performed in patients with left-sided lower abdominal pain, enabling a safer and more accurate procedure especially in patients with terminal cancer who are unable to lie prone owing to severe lower abdominal pain or with considerable anatomic deformation due to extensive growth, invasion, and metastasis of the tumor in the abdominal cavity.

Impact of Early Intervention in Pain Management in Cancer Patients: A Randomized Controlled Study in a Tertiary Care Cancer Hospital

OBJECTIVES

The present study aimed to assess the role of early intervention of nerve blocks in the management of cancer pain. We also aimed to study its effect on the quality of life and the opioid requirement.

MATERIALS AND METHODS

Sixty patients with cancer having pain, 18 to 75 years were randomised and divided into an intervention group and analgesic titration with opioids group. Patients in the intervention group received nerve block and residual pain managed with opioids. Control group patients were managed with opioids alone.

RESULTS

The mean visual analog scale score showed statistically significant improvement in both the groups (8.56±1.07 to 2.5±0.63 in the intervention group, 9.3±0.74 to 3.3±0.75 in the control group at 1 month (P=0.000). This was associated with a decrease in the opioid requirement in the intervention group at 1 week (P=0.014) with only 4 patients receiving morphine at the end of 1 month.The change in the Karnofsky scale was statistically significant from baseline to 1 month in both groups.

DISCUSSION

Interventional pain management has a definitive role in palliative setup for pain management. Pain relief was obtained in both groups, but the quality of pain relief was better in the intervention group with an associated reduction in the opioid requirement.

Dorsal Root Ganglion Stimulation for Chronic Pelvic Pain: A Case Series and Technical Report on a Novel Lead Configuration

INTRODUCTION

Chronic pelvic pain (CPP) is an elusive and complex neuropathic condition that is notoriously recalcitrant to treatment. The term "CPP" encompasses a number of treatment-resistant conditions like pudendal neuralgia, interstitial cystitis, coccygodynia, vulvodynia. CPP has been presented neuromodulators attempting to utilize conventional spinal cord stimulation (SCS), with constant frustration and high explant rates. Contrary to SCS, dorsal root ganglion stimulation (DRGS) delivers targeted target to focal areas, does not rely on paresthesias, and is able to reliably capture body parts like the pelvis making it an ideal modality for the treatment of CPP. We present seven patients with intractable CPP, resistant to conventional treatment methods, all successfully treated with DRGS.

METHODS

The case series includes seven patients with severe, CPP who failed to respond to a variety interventional treatments, and in some cases SCS. All seven patients were successfully trialed with DRGS utilizing leads placed over the bilateral L1 and S2 DRG's-to our knowledge, no publications describing either this particular lead configuration, or utilizing DRG stimulation on CPP, exist.

RESULTS

Following treatment, all seven patients experienced significant pain relief as well as reduction in opioid consumption and some cases improvement with sexual function and urination. Four of these patients have been implanted and continue to self-report sustained pain relief with high-satisfaction and functional improvement. To date no explants or instances of loss of efficacy have occurred (>1 year since implant).

CONCLUSION

Like most neuropathic pain states, CPP is resilient, difficult to manage, and typically unresponsive to the traditional therapeutics and SCS. Our case series demonstrates no only that DRGS is potentially effective, long-term treatment modality for CPP, but that the L1/S2 lead placement is the configuration of choice despite distinct differences in etiologies of pain and location.

Alleviating Pancreatic Cancer-Associated Pain Using Endoscopic Ultrasound-Guided Neurolysis

The most common symptom in patients with advanced pancreatic cancer is abdominal pain. This has traditionally been treated with nonsteroidal anti-inflammatory drugs and opioid analgesics. However, these treatments result in inadequate pain control or drug-related adverse effects in some patients. An alternative pain-relief modality is celiac plexus neurolysis, in which the celiac plexus is chemically ablated. This procedure was performed percutaneously or intraoperatively until 1996, when endoscopic ultrasound (EUS)-guided celiac plexus neurolysis was first described. In this transgastric anterior approach, a neurolytic agent is injected around the celiac trunk under EUS guidance. The procedure gained popularity as a minimally invasive approach and is currently widely used to treat pancreatic cancer-associated pain. We focus on two relatively new techniques of EUS-guided neurolysis: EUS-guided celiac ganglia neurolysis and EUS-guided broad plexus neurolysis, which have been developed to improve efficacy. Although the techniques are safe and effective in general, some serious adverse events including ischemic and infectious complications have been reported as the procedure has gained widespread popularity. We summarize reported clinical outcomes of EUS-guided neurolysis in pancreatic cancer (from the PubMed and Embase databases) with a goal of providing information useful in developing strategies for pancreatic cancer-associated pain alleviation.

Celiac Plexus Block and Neurolysis in the Management of Chronic Upper Abdominal Pain

Chronic upper abdominal pain occurs as a complication of various malignant and benign diseases including pancreatic cancer and chronic pancreatitis, and when present may contribute to lower quality of life and higher mortality. Though various pain management strategies are available as part of a multimodal approach, they are often incompletely effective and accompanied by side effects. Pain originating in upper abdominal viscera is transmitted through the celiac plexus, which is an autonomic plexus located in the retroperitoneum at the root of the celiac trunk. Direct intervention at the level of the plexus, referred to as celiac plexus block or neurolysis depending on the injectate, is a minimally invasive therapeutic strategy which has been demonstrated to decrease pain, improve function, and reduce opiate dependence. Various percutaneous techniques have been reported, but, with appropriate preprocedural planning, use of image guidance (usually computed tomography), and postprocedural care, the frequency and severity of complications is low and the success rate high regardless of approach. The main benefit of the intervention may be in reduced opiate dependence and opiate-associated side effects, which in turn improves quality of life. Celiac plexus block and neurolysis are safe and effective treatments for chronic upper abdominal pain and should be considered early in patients experiencing such symptoms.

The Optimal Approach for a Superior Hypogastric Plexus Block

INTRODUCTION

Superior hypogastric plexus block (SHGPB) is technically difficult, and an accurate procedure is required to avoid potential complications. We attempted to determine the reference angles for fluoroscopy-assisted SHGPB and to establish a predictor as a guide to select the optimal approach between the classic posterior approach and transdiscal approach.

METHODS

Abdominopelvic computed tomography (CT) scans from 268 patients diagnosed with pelvic malignancies were examined. The oblique and axial angles needed for the fluoroscope were measured both for posterior and transdiscal approaches by simulating the needle trajectory on CT imaging. We developed an SHGPB index defined by the ratio (%) of the interposterior iliac border distance to the L5 body transverse diameter, which represents the relative transverse diameter of the bony pelvis. We evaluated whether it can help select the optimal approach for the SHGPB between the posterior and transdiscal approaches.

RESULTS

Males had a significantly smaller angle than females (right oblique angle for posterior approach, males 14 [range 12 to 17] degrees vs. females 19 [range 16 to 23] degrees; P < 0.001). An SHGPB index of < 150 was an independent predictor for failure of the classic posterior approach (odds ratio 31.3, 95% confidence interval 5.1 to 104.7).

CONCLUSIONS

The optimal right oblique angle of fluoroscopy for the posterior approach is 13° to 15° in males and 19° to 20° in females. The transdiscal approach may be favored over the posterior approach when the bony pelvis is narrow relative to the target vertebral body, which can be measured by the SHGPB index being < 150.

Predictors of pain response in patients undergoing endoscopic ultrasound-guided neurolysis for abdominal pain caused by pancreatic cancer

BACKGROUND

Interventional endoscopic ultrasound (EUS)-guided procedures such as EUS-guided celiac ganglia neurolysis (EUS-CGN) and EUS-guided broad plexus neurolysis (EUS-BPN) were developed to treat abdominal cancer-associated pain; however, these procedures are not always effective. The aim of this study was to explore predictors of pain response in EUS-guided neurolysis for pancreatic cancer-associated pain.

METHODS

This was a retrospective analysis of prospectively collected data of 112 consecutive patients who underwent EUS-BPN in our institution. EUS-CGN was added in cases of visible celiac ganglia. The neurolytic-spread area was divided into six sections and evaluated by post-procedural computed tomography scanning. Pain intensity was assessed using a visual analog scale (VAS), and a decrease in VAS scores by ⩾3 points after neurolysis was considered a good pain response. Univariable and multivariable logistic regression analyses were performed to explore predictors of pain response at 1 and 4 weeks, and complications.

RESULTS

A good pain response was obtained in 77.7% and 67.9% of patients at 1 and 4 weeks, respectively. In the multivariable analysis of these patients, the combination method (EUS-BPN plus CGN) was a significant positive predictive factor at 1 week (odds ratio = 3.69, p = 0.017) and 4 weeks (odds ratio = 6.37, p = 0.043). The numbers of neurolytic/contrast spread areas (mean ± SD) were 4.98 ± 1.08 and 4.15 ± 1.12 in patients treated with the combination method and single method, respectively (p < 0.001). There was no significant predictor of complications.

CONCLUSIONS

EUS-BPN in combination with EUS-CGN was a predictor of a good pain response in EUS-guided neurolysis for pancreatic cancer-related pain. The larger number of neurolytic/contrast spread areas may lead to better outcomes in patients receiving combination treatment.

Presentation of Neurolytic Effect of 10% Lidocaine after Perineural Ultrasound Guided Injection of a Canine Sciatic Nerve: A Pilot Study

BACKGROUND

Phenol and alcohol have been used to ablate nerves to treat pain but are not specific for nerves and can damage surrounding soft tissue. Lidocaine at concentrations > 8% injected intrathecal in the animal model has been shown to be neurotoxic. Tests the hypothesis that 10% lidocaine is neurolytic after a peri-neural blockade in an ex vivo experiment on the canine sciatic nerve.

METHODS

Under ultrasound, one canine sciatic nerve was injected peri-neurally with 10 cc saline and another with 10 cc of 10% lidocaine. After 20 minutes, the sciatic nerve was dissected with gross inspection. A 3 cm segment was excised and preserved in 10% buffered formalin fixative solution. Both samples underwent progressive dehydration and infusion of paraffin after which they were placed on paraffin blocks. The sections were cut at 4 µm and stained with hemoxylin and eosin. Microscopic review was performed by a pathologist from Henry Ford Hospital who was blinded to which experimental group each sample was in.

RESULTS

The lidocaine injected nerve demonstrated loss of gross architecture on visual inspection while the saline injected nerve did not. No gross changes were seen in the surrounding soft tissue seen in either group. The lidocaine injected sample showed basophilic degeneration with marked cytoplasmic vacuolation in the nerve fibers with separation of individual fibers and endoneurial edema. The saline injected sample showed normal neural tissue.

CONCLUSIONS

Ten percent lidocaine causes rapid neurolytic changes with ultrasound guided peri-neural injection. The study was limited by only a single nerve being tested with acute exposure.

Alleviating visceral cancer pain in patients with pancreatic cancer using cryoablation and celiac plexus block

Little is known about the effects of pancreas cryoablation (PCA) on abdominalgia in pancreatic cancer patients or its synergism with celiac plexus block (CPB). In patients without abdominalgia, to investigate the effects of PCA; in patients with abdominalgia, to investigate the pain-alleviating effects of PCA+CPB. Sixty-two patients were enrolled in this retrospective review; 12 without abdominalgia refused PCA, 15 without abdominalgia received PCA to reduce their tumor load and 35 with abdominalgia received PCA+CPB to reduce tumor load and alleviate pain. All PCA and PCA+CPB procedures were performed successfully. Some slight adverse effects (e.g. increased serum amylase, abdominal distension and nausea, abdominal bleeding) had disappeared by 3weeks, spontaneously or after symptomatic treatment. In patients without abdominalgia, pain occurred in one-third of cases (all with pancreatic head cancer) after PCA but had stopped 1-12days after treatment; in patients with abdominalgia before treatment, pain stopped immediately after PCA+CPB in 18 cases and 2-24days after treatment in 17 (all with pancreatic head cancer); a significant difference was found between pretreatment and post-treatment pain frequency (P=0.0019), regardless of the presence of advanced (P=0.0096) or metastatic (P=0.0072) cancer. The average time to pain relief was approximately 7days after both PCA and PCA+CPB, and abdominalgia did not recur for more than 8weeks. PCA may cause short-term pain in some pancreatic cancer patients. Combined PCA+CPB can alleviate cancer pain for more than 8weeks, without severe side effects.

The role of chemical neurolysis in cancer pain

Pain continues to be a significant symptom burden in cancer patients, with prevalence in 53% of patients at all stages of cancer and as high as 58% to 69% in those with advanced cancer. Neurolytic blocks are a mainstay in the armamentarium of cancer pain management, more so in intractable pain from advanced cancer. There is no clear consensus on patient selection, technique, or timing of these blocks. Here we discuss the use of various neurolytic blocks for cancer pain and detail some of the recent literature and our experience.

EUS-guided broad plexus neurolysis over the superior mesenteric artery using a 25-gauge needle

OBJECTIVES

Endoscopic ultrasonography (EUS)-guided celiac plexus neurolysis (EUS-CPN) is safe and effective but not beneficial for some patients with extended abdominal cancer. We compared the effectiveness of standard EUS-CPN and EUS-guided broad plexus neurolysis (EUS-BPN) that extends over the superior mesenteric artery (SMA) using a 25-gauge needle.

METHODS

Consecutive patients referred to our quaternary EUS centers were eligible for inclusion. To evaluate the neurolytic spread, contrast was mixed with the neurolytic agent and post-procedure computed tomography scanning was performed. The regions containing the celiac, superior, and inferior mesenteric arteries were divided on the frontal plane into six areas: upper right and left, middle right and left, and lower right and left. The number of contrast-bearing areas after EUS-CPN and EUS-BPN were related to the degree of pain relief achieved.

RESULTS

A total of 67 patients with advanced abdominal cancer were included (34 EUS-CPN and 33 EUS-BPN). The qualitative variables of the two groups did not differ significantly. The EUS-BPN group had more patients with six contrast-bearing areas (42%) than the EUS-CPN group (0%). These patients had significantly better short-term and long-lasting pain relief than patients with less than five contrast-bearing areas. EUS-BPN patients exhibited significantly greater reductions in days 7 and 30 visual analog pain scale scores than EUS-CPN patients.

CONCLUSIONS

Our preliminary data suggested that EUS-BPN using a 25-gauge needle provides patients with advanced abdominal cancer with better pain relief than standard EUS-CPN, and without incurring serious complications. Moreover, it seems that broad neurolysis over the SMA may provide superior analgesia.

Interventional pain treatments for cancer pain

Cancer pain is prevalent and often multifactorial. For a segment of the cancer pain population, pain control remains inadequate despite full compliance with the WHO analgesic guidelines including use of co-analgesics. The failure to obtain acceptable pain or symptom relief prompted the inclusion of a fourth step to the WHO analgesic ladder, which includes advanced interventional approaches. Interventional pain-relieving therapies can be indispensable allies in the quest for pain reduction among cancer patients suffering from refractory pain. There are a variety of techniques used by interventional pain physicians, which may be grossly divided into modalities affecting the spinal canal (e.g., intrathecal or epidural space), called neuraxial techniques and those that target individual nerves or nerve bundles, termed neurolytic techniques. An array of intrathecal medications are infused into the cerebrospinal fluid in an attempt to relieve refractory cancer pain, reduce disabling adverse effects of systemic analgesics, and promote a higher quality of life. These intrathecal medications include opioids, local anesthetics, clonidine, and ziconotide. Intrathecal and epidural infusions can serve as useful methods of delivering analgesics quickly and safely. Spinal delivery of drugs for the treatment of chronic pain by means of an implantable drug delivery system (IDDS) began in the 1980s. Both intrathecal and epidural neurolysis can be effective in managing intractable cancer-related pain. There are several sites for neurolytic blockade of the sympathetic nervous system for the treatment of cancer pain. The more common sites include the celiac plexus, superior hypogastric plexus, and ganglion impar. Today, interventional pain-relieving approaches should be considered a critical component of a multifaceted therapeutic program of cancer pain relief.