Intrathecal Drug Delivery Systems for Refractory Pancreatic Cancer Pain: Observational Follow-up Study Over an 11-Year Period in a Comprehensive Cancer Center

Intrathecal drug delivery systems for cancer pain: A retrospective analysis at a single tertiary medical center in China

Objective

Intrathecal drug delivery systems (IDDS) have been clinically applied to treat refractory cancer-related pain for years. In this study, we demonstrate the current clinical practice and outcomes of IDDS for cancer pain management over a 3-year period at a single tertiary medical center in China.

Methods

Patients who received IDDS implantation for cancer-related pain from 2021 to 2023 were identified. The electronic medical records of all eligible patients were retrospectively reviewed for study data including baseline characteristics, IDDS variables and postoperative clinical outcomes.

Results

A total of 96 consecutive individuals were identified for analysis and complete follow-up information was available in 72 patients with a follow-up rate of 75 %. Patients were 49.0 % female with a mean age of 62 ± 10 years. The top five cancer types in IDDS population were lung (34.4 %), colorectal (17.7 %), pancreatic (11.5 %), breast (5.2 %) and liver (4.2 %) cancer. The median duration from cancer diagnosis to IDDS implantation was 24 months (interquartile range [IQR] 12-48 months) and from pain onset to IDDS implantation was 6 months (IQR 2-12 months). In addition, the median oral morphine equivalents (OME) daily dose was 290 mg (IQR 100-632 mg). Mean NRS was 7.5 ± 0.8 before implantation and decreased to an average of 3.0 ± 1.1 after IDDS (p < 0.001). Median overall survival after IDDS implantation was 3 months (IQR 2-6 months). Overall, 75 % family members of cancer patients were satisfied with IDDS in relieving cancer pain.

Conclusion

IDDS therapy is a valuable option for patients suffering from cancer pain. More and more cancer pain patients receive IDDS to treat pain during the 3-year study period.

Safety and Efficacy of Surgical Implantation of Intrathecal Drug Delivery Pumps in Patients With Cancer With Refractory Pain

BACKGROUND AND OBJECTIVES

Pain management in patients with cancer is a critical issue in oncology palliative care as clinicians aim to enhance quality of life and mitigate suffering. Most patients with cancer experience cancer-related pain, and 30%-40% of patients experience intractable pain despite maximal medical therapy. Intrathecal pain pumps (ITPs) have emerged as an option for achieving pain control in patients with cancer. Owing to the potential benefits of ITPs, we sought to study the long-term outcomes of this form of pain management at a cancer center.

METHODS

We retrospectively reviewed medical records of all adult patients with cancer who underwent ITP placement at a tertiary comprehensive cancer center between 2013 and 2021. Baseline characteristics, preoperative and postoperative pain control, and postoperative complication rate data were collected.

RESULTS

A total of 193 patients were included. We found that the average Numerical Rating Scale (NRS) score decreased significantly by 4.08 points (SD = 2.13, P < .01), from an average NRS of 7.38 (SD = 1.64) to an average NRS of 3.27 (SD = 1.66). Of 185 patients with preoperative and follow-up NRS pain scores, all but 9 experienced a decrease in NRS (95.1%). The median overall survival from time of pump placement was 3.62 months (95% CI: 2.73-4.54). A total of 42 adverse events in 33 patients were reported during the study period. The 1-year cumulative incidence of any complication was 15.6% (95% CI: 10.9%-21.1%) and for severe complication was 5.7% (95% CI: 3.0%-9.7%). Eleven patients required reoperation during the study period, with a 1-year cumulative incidence of 4.2% (95% CI: 2.0%-7.7%).

CONCLUSION

Our study demonstrates that ITP implantation for the treatment of cancer-related pain is a safe and effective method of pain palliation with a low complication rate. Future prospective studies are required to determine the optimal timing of ITP implantation.

Intrathecal cervical analgesia for cancer pain: a 12-year follow-up study in a comprehensive cancer center

BACKGROUND

Intrathecal analgesia plays a key role for patients suffering refractory cancer pain. Nevertheless, intrathecal drug delivery systems (IDDS), requiring a cervical catheter tip implantation, have been poorly described in medical literature.

AIMS

A monocentric retrospective follow-up study was designed to evaluate results of cervical IDDS for cancer pain.

PATIENTS AND METHODS

From January 2010 to December 2022, all intrathecal-treated patients were prescribed a combined intrathecal analgesics regimen through a catheter placed in the cervical vertebral canal. Post-implant assessment of pain was determined using a numeric rating scale (NRS). Patients were followed via day-hospital visits and telephone calls at least monthly. Pain scores were compared using the Wilcoxon's signed rank test.

RESULTS

Ninety-eight patients were included in this study; all received intrathecal treatments. Implanted patients suffered from severe pain (mean presurgical maximum numerical rating score 8.02±0.24 despite a mean 562.56±127.72 mg of oral morphine equivalent daily dose). Mean survival time after intrathecal treatment start was 208.48±67 days. Intrathecal drug delivery systems provided pain relief compared with initial pain score with a significant statistical difference after 1 week, 1 month, 2 and 3 months (p<0.01). A 50% reduction in initial pain level was achieved in 93% of cases during the first week of intrathecal implant.

CONCLUSIONS

Results suggest that long-term intrathecal treatment using a multidrug regimen for cancer-related pain through cervical intrathecal catheters was suitable and safe in our study population. We demonstrated a clinically and statistically significant pain reduction in patients using mainly a percutaneous lumbar approach.

The PATIENT Approach: A New Bundle for the Management of Chronic Pain

BACKGROUND

Chronic pain is one of the most challenging diseases for physicians as its etiology and manifestations can be extremely varied. Many guidelines have been published and many therapeutic options are nowadays available for the different types of pain. Given the enormous amount of information that healthcare providers must handle, it is not always simple to keep in mind all the phases and strategies to manage pain. We here present the acronym PATIENT (P: patient's perception; A: assessment; T: tailored approach; I: iterative evaluation; E: education; N: non-pharmacological approach; T: team), a bundle which can help to summarize all the steps to follow in the management of chronic pain.

METHODS

We performed a PubMed search with a list of terms specific for every issue of the bundle; only English articles were considered.

RESULTS

We analyzed the literature investigating these topics to provide an overview of the available data on each bundle's issue; their synthesis lead to an algorithm which may allow healthcare providers to undertake every step of a patient's evaluation and management.

DISCUSSION

Pain management is very complex; our PATIENT bundle could be a guide to clinicians to optimize a patient's evaluation and treatment.

Dorsal Versus Ventral Intrathecal Catheter Tip Location and Effect on Dose Escalation and Opioid Use in Patients With Cancer Pain

OBJECTIVES

In the practice of intrathecal drug delivery, consensus exists regarding the cephalad to caudad location of the catheter tip relative to dermatomal distribution of pain. However, data are lacking on the importance of dorsal vs ventral tip location relative to the spinal cord. We hypothesize that a dorsally placed catheter tip improves efficacy because of closer proximity to nociceptive pathways.

MATERIALS AND METHODS

A retrospective review of 298 patients with cancer with intrathecal drug delivery systems implanted at the Huntsman Cancer Institute from May 2014 to June 2020 was performed. Patients were stratified by catheter tip location zones based on available radiographic studies. Patient-controlled intrathecal medication dose requirements and rate of change were compared with catheter zone and other variables, including the presence of adjuncts such as bupivacaine and ziconotide.

RESULTS

A total of 158 patients were suitable for analysis demonstrating a dorsal tip in 63.9% (n = 101) and ventral tip in 36.1% (n = 57), with a median follow-up of 17 days (interquartile range [IQR], 10-24). There was no difference in daily dose change from implant to discharge between the dorsal group 8.2% (IQR, 0.0-41.5) and ventral group 20.8% (IQR, 0.0-66.7; p = 0.12). Daily dose change from discharge to follow-up was 2.6% (IQR, 0.0-7.1) in the dorsal group and 1.8% (IQR, 0.0-5.7) in the ventral group (p = 0.92). Catheter tip location had no impact on systemic opioid use.

CONCLUSIONS

We did not find significant associations between dorsal vs ventral catheter tip location and measures of pain relief, including change in intrathecal dose or systemic opioid use.

Refractory Cancer Pain and Intrathecal Therapy: Critical Review of a Systematic Review

This critical review assessed the advantages of invasive procedures that were recently included in systematic reviews, to evaluate whether the definition of refractory pain condition was correctly followed to select patients for invasive interventions and to analyze how data were positively interpreted. A total of 21 studies were selected for the purpose of this review. Three were randomized controlled studies, ten were prospective studies, and eight were retrospective studies. Analysis of these studies showed evident lack of proper assessment before implantation for different reasons. These included an optimistic interpretation regarding the outcomes, poor consideration of complications, and inclusion of patients with short survival. Moreover, the indication of intrathecal therapy as a condition in which a patient has failed to respond to multiple therapies provided by a pain or palliative care physician or at sufficient doses for adequate durations, as suggested by a recent research group, has been disregarded. Regretfully, this can discourage the use of intrathecal therapy in patients who are unresponsive to multiple opioid strategies subtrahend a potent means to be used in a very selective population.

Ziconotide for the Management of Cancer Pain: A Budget Impact Analysis

OBJECTIVES

Recent recommendations on starting dose, smaller dose increments, and longer intervals between dose increase have the potential to increase the safety of ziconotide administration in addition to improving its value for money. Ziconotide is not routinely commissioned in England, with one of the concerns being whether it represents the best use of resources. The aim of this project is to conduct a budget impact analysis to estimate the costs or savings associated with the changes in ziconotide dosage in addition to its use in combination with morphine for the management of cancer pain.

MATERIALS AND METHODS

An open, Markov-like cohort decision analytic model was developed to estimate the budget impact of ziconotide in combination with morphine (ziconotide combination therapy) vs morphine monotherapy through intrathecal drug delivery (ITDD) for the management of cancer pain. The perspective adopted was that of the UK National Health Service, with a five-year time horizon. Sensitivity analyses were conducted to evaluate different scenarios.

RESULTS

Ziconotide combination therapy was more expensive than treatment with morphine monotherapy. The total costs of ziconotide combination therapy and morphine monotherapy for the first year were £395,748 and £136,628 respectively. The estimated five-year cumulative budget impact of treatment with ziconotide combination therapy for the five-year time horizon was £2,487,539, whereas that of morphine monotherapy was £913,804. The additional costs in any of the first five years are below the resource impact significance level of £1 million for medical technologies in England.

CONCLUSIONS

The results of this budget impact analysis suggest that although a combination of intrathecal ziconotide in combination with morphine is associated with higher costs to the health care system in England, the incremental costs are not significant. Routine commissioning of ziconotide alone or in combination with morphine would provide an alternative for a population with limited ITDD treatment options.

Controversies in intrathecal drug delivery for cancer pain

Pain and suffering related to cancer are challenging issues that continue to deserve consideration for treatment optimization. Advances in analgesic management and control of the underlying cancer have improved symptom management, yet many patients still suffer from uncontrolled pain. Intrathecal drug delivery has an established role in the management of refractory cancer pain, but there are significant knowledge gaps in our understanding and application of this therapy. This review addresses several areas of controversy, including the importance of intrathecal catheter tip location, the necessity of an intrathecal trial and the role of intrathecal ziconotide and local anesthetics. In each area, the evidence is discussed, with an emphasis on presenting practical clinical guidance and highlighting deficiencies in our knowledge that are worthy of future investigation.

Effectiveness and Safety of Intrathecal Drug Delivery Systems for the Management of Cancer Pain: A Systematic Review and Meta-Analysis

OBJECTIVES

Intrathecal drug delivery systems (IDDS) and spinal cord stimulation (SCS) have been proposed and assessed for the management of cancer pain; however, such treatments remain underused. We conducted a systematic review to evaluate the effectiveness and safety of IDDS and SCS for cancer pain.

MATERIALS AND METHODS

Electronic databases MEDLINE, CENTRAL, EMBASE, and WikiStim were searched from 1988 to March 2021. Randomized controlled trials and observational studies of adults with pain related to cancer or its treatment who received an implantable IDDS or SCS were eligible for inclusion. The primary outcome of the review was change in pain intensity from baseline to the last available follow-up, measured using a visual analog scale or numerical rating scale. The protocol for this review is registered on PROSPERO (CRD42021240717).

RESULTS

A total of 22 studies (24 reports) included a total of 3043 participants who received either IDDS or SCS for cancer pain. Eight studies reporting data for 405 participants with an IDDS could be included in the meta-analysis of pain intensity that showed a statistically significant reduction at the latest posttreatment follow-up time compared with baseline (mean difference [MD], -3.31; 95% CI, -4.18 to -2.45; p < 0.001). Six studies reporting data for 325 participants with an IDDS could be included in the meta-analysis of pain intensity that showed a statistically significant reduction up to one month after treatment compared with baseline (MD, -3.53; 95% CI, -4.06 to -3.00; p < 0.001). A meta-analysis including studies of participants with either an IDDS or an SCS device showed similar results. Improvements in other outcomes following implantation of IDDS also were observed. Postdural puncture headache was the most reported complication, whereas urinary retention, nausea, and vomiting were commonly reported side effects.

CONCLUSION

Our findings suggest that IDDS is effective in reducing pain intensity for patients with cancer pain when compared with pretreatment.

Management of Cancer-Related Pain With Intrathecal Drug Delivery: A Systematic Review and Meta-Analysis of Clinical Studies

BACKGROUND

Despite increased attention paid to assessment and management, pain continues to be a prevalent and undertreated symptom in patients with cancer. Intrathecal drug delivery (IDD) is a therapeutic option that allows targeted delivery of analgesics to the intrathecal space.

OBJECTIVE

The aim of this review was to examine the efficacy of managing cancer-related pain with IDD. Secondary objectives included the effects of IDD on systemic opioid use and infection rates.

EVIDENCE REVIEW

A systematic search of the literature published between 1990 and 2019 was performed to identify studies evaluating the efficacy and/or safety of IDD with external or implanted pumps in patients with cancer-related pain. Data were extracted and meta-analyses performed to determine the mean changes in pain levels at short-, mid-, and long-term intervals; changes in opioid (oral morphine equivalent [OME]) daily dose; and infection rates. Changes were assessed compared with baseline.

FINDINGS

Pain levels were decreased from baseline: On a 0 to 10 scale, mean differences were -4.34 (95% CI [-4.93 to -3.75], p < 0.001) at 4 to 5 weeks; -4.34 (95% CI [-5.07 to -3.62], p < 0.001) at 6 to 12 weeks; and -3.32 (95% CI [-4.60 to -2.04], p < 0.001) at >6 months. Weighted mean OME consumption was reduced by 308.24 (SE = 22.72) mg/d. Weighted mean infection rates were ∼3% for external and implanted pumps.

CONCLUSIONS

Meta-analyses show a statistically significant and sustained decrease in cancer pain with IDD, compared with baseline. Systemic opioid consumption was reduced on average by >50% after IDD. Infection rates were comparable with other indications.

Intrathecal Analgesia in Cancer Pain

The number of new cancer cases has been increasing globally over the last several decades.

Initial Intrathecal Dose Titration and Predictors of Early Dose Escalation in Patients With Cancer Using a 100:1 Oral to Intrathecal Morphine Conversion Ratio

OBJECTIVE

Pain is common in patients with advanced cancer, and intrathecal drug delivery (IDD) has been successfully used for recalcitrant pain. We report on our experience using a 100:1 oral-to-intrathecal morphine conversion ratio for initial dosing and factors predictive of early dose escalation.

MATERIALS AND METHODS

Retrospective review of an intrathecal drug delivery system (IDDS) data base at the Huntsman Cancer Institute-University of Utah in cancer patients initiated on IDD with morphine or hydromorphone. Demographic characteristics, preoperative opioid use, and initial and hospital discharge IDD settings were collected.

RESULTS

A total of 275 patients were identified between June 2014 and May 2020. The median oral-to-intrathecal morphine conversion ratio for initial IDD dosing was 105.5:1 (interquartile range [IQR] 90-120, range 75-150). No serious adverse effects including respiratory depression or sedation were noted and the median length of stay was one night (IQR 1-2, range 1-22). Ninety-six percent of patients discontinued opioids immediately following IDDS implant. Initial IDD dosing was adequate in 42% of patients. Dose reduction was required in 4% prior to discharge due to nausea, patient request, weakness, pruritus, or urinary retention. Dose escalation was required in 54%, with a median dose increase of 66.7% (IQR 33-150%, range 5-1150%). Patients in the highest quartile of dose escalation, ≥70% between IDD initiation and discharge, had associations with younger age, higher preoperative opioid use, and inpatient status. No significant associations were found in patients who required dose reduction as compared to other patients.

CONCLUSIONS

An oral-to-intrathecal morphine conversion ratio of approximately 100:1 for initiation of IDD in patients with cancer pain was safe and well tolerated and may facilitate rapid elimination of systemic opioids. Dose reduction was rare, while a majority of patients required further dose escalation prior to discharge.

The American Society of Pain and Neuroscience (ASPN) Best Practices and Guidelines for the Interventional Management of Cancer-Associated Pain

Moderate to severe pain occurs in many cancer patients during their clinical course and may stem from the primary pathology, metastasis, or as treatment side effects. Uncontrolled pain using conservative medical therapy can often lead to patient distress, loss of productivity, shorter life expectancy, longer hospital stays, and increase in healthcare utilization. Various publications shed light on strategies for conservative medical management for cancer pain and a few international publications have reviewed limited interventional data. Our multi-institutional working group was assembled to review and highlight the body of evidence that exists for opioid utilization for cancer pain, adjunct medication such as ketamine and methadone and interventional therapies. We discuss neurolysis via injections, neuromodulation including targeted drug delivery and spinal cord stimulation, vertebral tumor ablation and augmentation, radiotherapy and surgical techniques. In the United States, there is a significant variance in the interventional treatment of cancer pain based on fellowship training. As a first of its kind, this best practices and interventional guideline will offer evidenced-based recommendations for reducing pain and suffering associated with malignancy.

Gabapentin enhances the antinociceptive effect of intrathecal morphine in refractory cancer pain patients

PURPOSE

Morphine infusion through Intrathecal Drug Delivery System (IDDS) is widely used to relieve refractory cancer pain. However, continuous escalation of morphine dose caused by opioid tolerance and/or progress of cancer was commonly observed. Combining morphine with medications of different analgesic mechanisms is applied to blunt the rate of morphine increase. The purpose of this study was to determine the analgesic efficacy and safety of combining gabapentin with morphine after IDDS implantation.

METHODS

This study compared patients that received IDDS implantation from January 1, 2017 to November 10, 2018 in our institute. Key outcomes included change in mean pain score, dose of morphine used in patients, percentage of patients with 30% and 50% reduction in mean pain score, Patient Global Impression of Change scores, breakthrough pain characters and side effects.

RESULTS

34 patients in the combination group (morphine + gabapentin) and 40 patients in the monotherapy group(morphine)were analyzed. The results showed that both therapy groups achieved similar analgesic efficacy, demonstrated by Numerical rating scale (2.42 ± 0.88 vs 2.57 ± 0.85; Combination vs Monotherapy), PGIC and responder status. Mean daily dose of morphine was significantly lower in combination group compared to monotherapy group (3.54 ± 1.29 mg vs 4.64 ± 1.28 mg, P = 0.007). More patients experienced dizziness and somnolence after receiving combination therapy compared to morphine-alone treatment although no statistical significance was found (P = 0.49).

CONCLUSION

Addition of gabapentin achieved similar analgesic efficacy with lower dose of morphine compared to morphine alone accompanying with higher incidence of dizziness and somnolence.

Pancreas Cancer-Associated Pain Management

Pain is highly prevalent in patients with pancreas cancer and contributes to the morbidity of the disease. Pain may be due to pancreatic enzyme insufficiency, obstruction, and/or a direct mass effect on nerves in the celiac plexus. Proper supportive care to decrease pain is an important aspect of the overall management of these patients. There are limited data specific to the management of pain caused by pancreatic cancer. Here we review the literature and offer recommendations regarding multiple modalities available to treat pain in these patients. The dissemination and adoption of these best supportive care practices can improve quantity and quality of life for patients with pancreatic cancer. IMPLICATIONS FOR PRACTICE: Pain management is important to improve the quality of life and survival of a patient with cancer. The pathophysiology of pain in pancreas cancer is complex and multifactorial. Despite tumor response to chemotherapy, a sizeable percentage of patients are at risk for ongoing cancer-related pain and its comorbid consequences. Accordingly, the management of pain in patients with pancreas cancer can be challenging and often requires a multifaceted approach.

Intrathecal pain management with ziconotide: Time for consensus?

This article summarizes recommendations made by six pain specialists who discussed the rationale for ziconotide intrathecal analgesia (ITA) and the requirement for evidence-based guidance on its use, from a European perspective. Riemser Pharma GmbH (Greifswald, Germany), which holds the European marketing authorization for ziconotide, hosted the meeting. The group agreed that ITA is under-used in Europe, adding that ziconotide ITA has potential to be a first-line alternative to morphine; both are already first-line options in the USA. Ziconotide ITA (initiated using a low-dose, slow-titration approach) is suitable for many patients with noncancer- or cancer-related chronic refractory pain and no history of psychosis. Adopting ziconotide as first-line ITA could reduce opioid usage in these patient populations. The group advocated a risk-reduction strategy for all candidate patients, including compulsory prescreening for neuropsychosis, and requested US-European alignment of the licensed starting dose for ziconotide: the low-and-slow approach practiced in the USA has a better tolerability profile than the fixed high starting dose licensed in Europe. Of note, an update to the European Summary of Product Characteristics is anticipated in early 2021. The group acknowledged that the Polyanalgesic Consensus Conference (PACC) treatment algorithms for ziconotide ITA provide useful guidance, but recommendations tailored specifically for European settings are required. Before a consensus process can formally begin, the group called for additional European prospective studies to investigate ziconotide in low-and-slow dosing strategies, in different patient settings. Such data would enable European guidance to have the most appropriate evidence at its core.

Narrative review of intrathecal drug delivery (IDD): indications, devices and potential complications

The management of chronic refractory pain (non-neoplastic and cancer-related pain) remains a therapeutic challenge. The continuous intrathecal (IT) administration of drugs may play an important role in the possible management options. Intrathecal drug delivery devices (IDDDs) may be effective for patients with refractory chronic pain. Therefore, they may be adopted for non-oncologic pain in patients with compression fractures, spondylolisthesis, spondylosis, back surgery failure syndrome and spinal stenosis. Oncologic patients can benefit from these treatments in a variable way according to tumor characteristics, prognosis, periprocedural imaging and risk of disease progression. In this review, we describe the most commonly used drugs (opioids and non-opioids), their pharmacokinetic and pharmacodynamic features and indications of use. The most used drugs are morphine, hydromorphone, fentanyl, methadone, bupivacaine, clonidine, and ketamine. Patient evaluation before the device implantation should be based on clinical examination, medical records assessment and psychometric evaluation. The infusion pumps available on the market are both non-programmable (with continuous IT deliver of drugs) and programmable (with variable deliver of drugs according to their flow rate). Moreover, we describe the procedure of implantation and the potential complications of IT drug delivery (such as bleeding, infection, loss of cerebrospinal fluid, wound seroma, loss of catheter pump propellant).

A Rare Complication of Ileus Following Endoscopic Ultrasound-Guided Celiac Plexus Neurolysis: A Case Report

Pancreatic cancer patients experience debilitating pain, which makes pain management an integral part of the treatment plan. Endoscopic ultrasound-guided celiac plexus neurolysis (EUS-guided CPN) is an alternative palliative therapy for patients with pain due to pancreatic cancer. We report a patient who developed paralytic ileus after undergoing EUS-guided CPN. 

A 77-year-old male patient presented with nausea, vomiting, and abdominal pain of one-day duration. He was diagnosed with stage IV pancreatic adenocarcinoma three weeks prior to presentation for which he underwent EUS-guided CPN. He had a 30-pack-year smoking history and quit 31 years ago. He reported moderate alcohol use and denied illicit drug use. In the emergency department, vital signs demonstrated normal blood pressure, heart rate, respiratory rate, and temperature. Abdominal exam was significant for minimal epigastric tenderness without guarding or rebound. Complete blood count (CBC), basic metabolic panel (BMP), and liver function tests were unremarkable. Computed tomography (CT) scan of the abdomen showed significant gastric distension. Esophagogastroduodenoscopy (EGD) showed large amounts of fluids within the gastric fundus and body. Upper gastrointestinal series showed delayed gastric emptying of the contrast, but contrast was seen in the third part of the duodenum and jejunum. Push enteroscopy showed no obstruction or mucosal abnormalities in the third or fourth parts of the duodenum. Small bowel obstruction was ruled out, and the diagnosis of ileus was made. The patient received ondansetron and polyethylene glycol as needed, and his diet was advanced slowly. His symptoms improved over the course of a few days, and he experienced a return of normal bowel activity. He eventually tolerated a regular diet and was discharged home in a stable condition.

Although EUS-guided CPN is a safe procedure, the procedure resulted in an unexpected ileus that has rarely been reported in the literature. Future studies with large sample sizes are recommended to capture the occurrence of the rare side effects of EUS-guided CPN.

Endogenous Opiates and Behavior: 2018

This paper is the forty-first consecutive installment of the annual anthological review of research concerning the endogenous opioid system, summarizing articles published during 2018 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides and receptors as well as effects of opioid/opiate agonists and antagonists. The review is subdivided into the following specific topics: molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors (2), the roles of these opioid peptides and receptors in pain and analgesia in animals (3) and humans (4), opioid-sensitive and opioid-insensitive effects of nonopioid analgesics (5), opioid peptide and receptor involvement in tolerance and dependence (6), stress and social status (7), learning and memory (8), eating and drinking (9), drug abuse and alcohol (10), sexual activity and hormones, pregnancy, development and endocrinology (11), mental illness and mood (12), seizures and neurologic disorders (13), electrical-related activity and neurophysiology (14), general activity and locomotion (15), gastrointestinal, renal and hepatic functions (16), cardiovascular responses (17), respiration and thermoregulation (18), and immunological responses (19).

The Rate of Infectious Complications After Intrathecal Drug Delivery System Implant for Cancer-Related Pain Is Low Despite Frequent Concurrent Anticancer Treatment or Leukopenia

BACKGROUND

The efficacy of intrathecal drug delivery (IDD) for cancer-related pain is well established. Cancer therapies are often associated with immunosuppression and increased risk of infection, and the rate of infection after intrathecal drug delivery system (IDDS) implant in cancer patients has been reported as 2.4%-6.3%. Our objective is to report on the rate of surgical site infections (SSI) in patients implanted with IDDS for cancer-related pain and to provide a data-driven discussion on the relationship between antineoplastic treatment, leukopenia, and other clinical or demographic characteristics and SSI.

METHODS

Following local institutional review board approval, we conducted a retrospective chart review of IDDS implants from May 2014 through December 2018. Data collected included demographic data, health status, prophylactic antibiotic administration, surgery duration, presence of leukopenia (white blood cell [WBC] count of <4.0 K/µL) or moderate neutropenia (absolute neutrophil count [ANC] of <1000/μL) within the 30 days before IDDS implant, and details of antineoplastic treatment or systemic corticosteroid use in the perioperative period. This information was assessed in relation to SSI incidence up to 6 months following implant.

RESULTS

Two hundred seventeen IDDS implants were identified. A majority of patients (79.3%) received ≥1 form of antineoplastic therapy within 30 days before or after implant, and 42.4% received multiple forms of antineoplastic therapy. Therapies included chemotherapy in 46.5%, immunotherapy in 28.6%, systemic steroids in 32.3%, and radiation therapy in 28.1%. One-quarter of patients (25.8%) were leukopenic within 30 days before implant, with 3.2% having moderate neutropenia. There were 2 infectious complications representing an infection rate of 0.9% (95% CI, 0.1%-3.3%), with limited shared characteristics between those experiencing SSI.

CONCLUSIONS

SSI risk after IDDS placement for cancer pain is low, despite frequent concurrent antineoplastic therapy and leukopenia in the perioperative period. Concomitant cancer therapies should not be a barrier to the implementation of IDD for cancer pain.

Initiation of Intrathecal Drug Delivery Dramatically Reduces Systemic Opioid Use in Patients With Advanced Cancer

OBJECTIVES

Pain is common in cancer, affecting more than 70% of patients with advanced disease. Intrathecal drug delivery systems (IDDS) are a well-established treatment for patients with refractory cancer pain, improving pain control and reducing associated side effects. To date, details of systemic opioid use before and after IDDS implant have not been reported.

MATERIALS AND METHODS

We conducted a retrospective review of patients at Huntsman Cancer Institute-University of Utah treated with IDDS for cancer pain from May 2014 to May 2018. Oral, transdermal, and parenteral opioid use before IDDS implant was compared to use 30 days postoperatively.

RESULTS

A total of 173 patients were included, 93% with stage IV disease. The pre-implant median daily oral morphine equivalent (OME) was 240 mg (interquartile range 130-390, range 0-2616 mg). OME doses >200 mg/day were required by 57% of patients, and >500 mg OME by 19% of patients. The post-implant median OME was 0 mg (interquartile range 0-0, range 0-480 mg) and 82.6% of patients discontinued systemic opioids completely. 11.0% of patients used <100 mg OME, and only 1.7% of patients used >200 mg OME. Mean OME decreased by 94% following IDDS implant (p < 0.0001) and all patients who continued to use systemic opioids required a lower OME compared to pre-implant.

CONCLUSIONS

In the largest cohort of patients with advanced cancer and refractory pain treated with IDDS, implantation was associated with a dramatic reduction in systemic opioid use 30 days postoperatively, with a large majority of patients discontinuing systemic opioids. Those patients that continued systemic opioids utilized significantly lower doses as compared to their pre-implant dose.

Prospective Association of Serum Opioid Levels and Clinical Outcomes in Patients With Cancer Pain Treated With Intrathecal Opioid Therapy

BACKGROUND

Opioids remain the mainstay of cancer pain management but are associated with systemic toxicity. In refractory cancer pain, intrathecal therapy (ITT) is associated with improved pain control, reduced systemic side effects, and improved survival. It has been assumed that ITT decreases systemic serum opioid levels and their associated toxicity, but there are limited data to support this assumption. This study hypothesizes that serum opioid levels decrease with ITT. Secondary objectives include comparative measures of pain, bowel function, and other cancer-related symptoms.

METHODS

Fifty-one cancer patients undergoing ITT for cancer pain were recruited in a prospective observational study. Daily oral morphine equivalency (OME) dose, serum opioid levels, Brief Pain Inventory (BPI), MD Anderson Symptom Inventory (MDASI), and a constipation questionnaire were obtained at the time of implant, and 4 and 8 weeks postoperatively.

RESULTS

Average baseline daily OME was 375 mg (median, 240; interquartile range, 150-405; range, 0-3160), mean serum morphine concentration was 53.7 ng/mL (n = 17), and mean oxycodone concentration was 73.7 ng/mL (n = 20). At 4 weeks, 87.5% of patients had discontinued non-IT opioids, and 53% had undetectable (<2 ng/mL) serum opioid concentrations. At 8 weeks, 92% remained off all non-IT opioids and 59% had undetectable serum opioid levels. IT morphine doses >4.2 mg/d were invariably associated with detectable serum levels; with doses <4.2 mg, morphine was undetectable in 80% of subjects. IT hydromorphone doses >6.8 mg/d were detectable in the serum. Using linear mixed model analyses, there were statistically significant decreases in the mean "worst pain," "average pain," and MD Anderson symptom severity and interference scores at 4 and 8 weeks. This change was independent of serum opioid levels; when analyzed separately, there was no difference in the pain scores of subjects with detectable serum opioid levels compared to those with undetectable levels at 4 and 8 weeks. Constipation ranked as "quite a bit" or "very much" decreased from 58.7% to 19.2% of subjects at week 4 (P < .001) and to 37.5% at 8 weeks (P = .23). A very low complication rate was observed.

CONCLUSIONS

ITT for cancer pain was associated with a marked reduction in serum opioid concentrations, with the majority of patients having undetectable serum levels. Reducing serum opioid concentrations in cancer patients may have implications with respect to restoring bowel function, improving fatigue, and promoting the integrity of antitumor immune function and warrants further study.

Intrathecal Drug Delivery

Targeted intrathecal (IT) drug delivery systems (IDDS) are well established as an effective treatment of patients with chronic nonmalignant or malignant pain, and as a tool for management of patients with severe spasticity. The risk to benefit ratio of IDD makes it a relatively safe therapy for both cancer- and noncancer-related pain, but it is not free of risks, so it should be managed at specific centers. Recent technological advances, new therapeutic applications, reported complications, and the costs as well as maintenance required for this therapy require the need to stay up to date about new recommendations that may improve outcomes. This chapter reviews all technological issues regarding IDDS implantation with follow-up and pharmacological recommendations published during recent years that provide evidence-based decision-making process in the management of chronic pain and spasticity in patients.

Pancreatic cancer-A disease in need: Optimizing and integrating supportive care

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive malignancy that continues to be challenging to treat. PDAC has the lowest 5-year relative survival rate compared with all other solid tumor malignancies and is expected to become the second-leading cause of cancer-related death in the United States by 2030. Given the high mortality, there is an increasing role for concurrent anticancer and supportive care in the management of patients with PDAC with the aims of maximizing length of life, quality of life, and symptom control. Emerging trends in supportive care that can be integrated into the clinical management of patients with PDAC include standardized supportive care screening, early integration of supportive care into routine cancer care, early implementation of outpatient-based advance care planning, and utilization of electronic patient-reported outcomes for improved symptom management and quality of life. The most common symptoms experienced are nausea, constipation, weight loss, diarrhea, anorexia, and abdominal and back pain. This review article includes current supportive management strategies for these and others. Common disease-related complications include biliary and duodenal obstruction requiring endoscopic procedures and venous thromboembolic events. Patients with PDAC continue to have a poor prognosis. Systemic therapy options are able to palliate the high symptom burden but have a modest impact on overall survival. Early integration of supportive care can lead to improved outcomes.

Strategies for interventional therapies in cancer-related pain-a crossroad in cancer pain management

PURPOSE

Interventional therapies are important to consider when facing cancer pain refractory to conventional therapies. The objective of the current review is to introduce these effective strategies into dynamic interdisciplinary pain management, leading to an exhaustive approach to supportive oncology.

METHODS

Critical reflection based on literature analysis and clinical practice.

RESULTS

Interventional therapies act on the nervous system via neuromodulation or surgical approaches, or on primitive or metastatic lesions via interventional radiotherapy, percutaneous ablation, or surgery. Interventional therapies such as neuromodulations are constantly evolving with new technical works still in development. Nowadays, their usage is better defined, depending on clinical situations, and their impact on quality of life is proven. Nevertheless their availability and acceptability still need to be improved. To start with, a patient's interdisciplinary evaluation should cover a wide range of items such as patient's performance and psychological status, ethical considerations, and physiochemical and pharmacological properties of the cerebrospinal fluid for intrathecal neuromodulation. This will help to define the most appropriate strategy. In addition to determining the pros and cons of highly specialized interventional therapies, their relevance should be debated within interdisciplinary teams in order to select the best strategy for the right patient, at the right time.

CONCLUSIONS

Ultimately, the use of the interventional therapies can be limited by the requirement of specific trained healthcare teams and technical support, or the lack of health policies. However, these interventional strategies need to be proposed as soon as possible to each patient requiring them, as they can greatly improve quality of life.

Opening up disruptive ways of management in cancer pain: the concept of multimorphic pain

PURPOSE

Following a series of articles reviewing the basics of cancer pain management, in this article, we develop the guiding principle of our philosophy: the concept of multimorphic pain and how to integrate it as the innovative cornerstone of supportive care in cancer.

METHOD

Critical reflection based on literature analysis and clinical practice.

RESULTS

This model aims to break with standard approaches, offering a more dynamic and exhaustive vision of cancer pain as a singular clinical entity, taking into account its multimorphic characteristics (cancer pain experience can and will change during cancer: aetiology, physiopathology, clinical presentation and consequences of pain) and the disruptive elements that can occur to influence its evolution (cancer evolution, concomitant treatments, pain from associated diseases, comorbidities and complications, or modifications in the environment). Our model establishes the main key stages for interdisciplinary management of cancer pain: Early, personalised management that is targeted and multimodal; Identification, including in advance, of potential disruptive elements throughout the care pathway, using an exhaustive approach to all the factors influencing pain, leading to patient and caregiver education; Optimal analgesic balance throughout the care pathway; Integration of this concept into a systemic early supportive care model from the cancer diagnosis.

CONCLUSIONS

Given the difficulties still present in the management of pain in cancer, and whilst cancer is often considered as a chronic condition, the concept of multimorphic pain proposes a practical, optimised and innovative approach for clinicians and, ultimately, for patients experiencing pain.

Optimizing Initial Intrathecal Drug Ratio for Refractory Cancer-Related Pain for Early Pain Relief. A Retrospective Monocentric Study

Objective

Intrathecal (IT) drug delivery has shown its efficiency in treating refractory cancer pain, but switching opioids from the systemic to the intrathecal route is a challenging phase. Moreover, associations are widely used and recommended. Few data deal with the initial dosage of each drug. Analyzing conversion factors and initial dosages used in intrathecal therapy seems essential to decreasing the length of titration and to delivering quick pain relief to patients.

Methods

We retrospectively analyzed data from consecutive adult patients implanted with an intrathecal device for cancer pain and treated at the Institut de Cancérologie de l’Ouest, in Angers, France, for four years. The main goal was to identify factors associated with early pain relief after intrathecal drug delivery system (IDDS) implantation.

Results

Of the 220 IDDS-treated patients, 70 (32%) experienced early pain relief (EaPR) and 150 (68%) delayed pain relief (DePR). Performance Status stage and initial IT ropivacaine:IT morphine ratio were the variables independently associated with EaPR. The best IT ropivacaine:IT morphine ratio to predict EaPR was 5:1, with a 73% (95% confidence interval [CI] = 64.8% to 79.6%) sensitivity and a 67.1% (95% CI = 54.9% to 77.9%) specificity. EaPR subjects experienced better pain relief (–84% vs –60% from baseline pain score, P < 0.0001), shorter length of hospitalization (7 vs 10 days, P < 0.0001), and longer survival (155 vs 82 days, P = 0.004).

Conclusions

Local anesthetic:morphine ratio should be considered when starting IDDS treatment. EaPR during the IT analgesia titration phase was associated with better pain relief and outcomes in patients with refractory cancer-related pain.