Retrospective Analysis of Intrathecal Drug Delivery: Outcomes, Efficacy, and Risk for Cancer-Related Pain at a High Volume Academic Medical Center

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 morphine delivery at prepontine cistern to control refractory cancer-related pain: a case report of extensive metastatic and refractory cancer pain

BACKGROUND

Extensive metastatic and refractory cancer pain is common, and exhibits a dissatisfactory response to the conventional intrathecal infusion of opioid analgesics.

CASE PRESENTATION

The present study reports a case of an extensive metastatic esophageal cancer patient with severe intractable pain, who underwent translumbar subarachnoid puncture with intrathecal catheterization to the prepontine cistern. After continuous infusion of low-dose morphine, the pain was well-controlled with a decrease in the numeric rating scale (NRS) of pain score from 9 to 0, and the few adverse reactions to the treatment disappeared at a low dose of morphine.

CONCLUSIONS

The patient achieved a good quality of life during the one-month follow-up period.

Minimally Invasive Bleb Surgery for Glaucoma: A Health Technology Assessment

Background

Glaucoma is the term for a group of eye disorders that causes progressive damage to the optic nerve, which can lead to visual impairment and, potentially, irreversible blindness. Minimally invasive bleb surgery (MIBS) reduces eye pressure through the implantation of a device that creates a new subconjunctival outflow pathway for eye fluid drainage. MIBS is a less invasive alternative to conventional/incisional glaucoma surgery (e.g., trabeculectomy). We conducted a health technology assessment of MIBS for people with glaucoma, which included an evaluation of effectiveness, safety, the budget impact of publicly funding MIBS, and patient preferences and values.

Methods

We performed a systematic literature search of the clinical evidence. We assessed the risk of bias of each included study using the Cochrane Risk of Bias 1.0 tool for randomized controlled trials (RCTs) and the Risk of Bias Assessment tool for Nonrandomized Studies (RoBANS) for comparative observational studies, and the quality of the body of evidence according to the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) Working Group criteria. We conducted an economic literature search and we estimated the budget impact of publicly funding MIBS in Ontario. We did not conduct a primary economic evaluation due to the limited long-term effectiveness data. We summarized the preferences and values evidence from previous health technology assessments to understand the perspectives and experiences of patients with glaucoma.

Results

We included 41 studies (2 RCTs and 39 comparative observational studies) in the clinical evidence review. MIBS may reduce intraocular pressure and the number of medications used, but we are uncertain if MIBS results in outcomes similar to trabeculectomy (GRADE: Moderate to Very low). Compared with trabeculectomy, MIBS may result in fewer follow-up visits and interventions, and adverse events (GRADE: Moderate to Very Low). MIBS may also reduce intraocular pressure and the number of antiglaucoma medications used, compared with other glaucoma treatments, but the evidence is uncertain (GRADE: Very low). Our economic evidence review identified two directly applicable studies. The results of these studies indicate that the cost-effectiveness of MIBS is highly uncertain, and the cost of glaucoma interventions are likely to vary across provinces. The annual budget impact of publicly funding MIBS in Ontario ranged from $0.11 million in year 1 to $0.67 million in year 5, for a total 5-year budget impact estimate of $1.93 million. Preferences and values evidence suggests that fear of ultimate blindness and difficulty managing medication for glaucoma led patients to explore other treatment options such as MIBS. Glaucoma patients found minimally invasive glaucoma surgery (MIGS) procedure beneficial, with minimal side effects and recovery time.

Conclusions

Minimally invasive bleb surgery reduces intraocular eye pressure and the number of antiglaucoma medications needed, but we are uncertain if the outcomes are similar to trabeculectomy (GRADE: Moderate to Very low). However, MIBS may be safer than trabeculectomy (GRADE: Moderate to Very low) and result in fewer follow-ups (GRADE: Moderate to Very low). MIBS may also improve glaucoma symptoms compared with other glaucoma treatments, but the evidence is very uncertain (GRADE: Very low).We estimate that publicly funding MIBS would result in an additional cost of $1.93 million over 5 years. Patients who underwent MIGS procedures found them to be generally successful and beneficial, with minimal side effects and recovery time. We could not draw conclusions about specific MIBS procedures or long-term outcomes.

Intrathecal Drug Delivery Systems for Cancer Pain: A Health Technology Assessment

Background

Pain is a common and very distressing symptom for adults and children with cancer. Compared with other routes of delivery, infusing pain medication directly into the intrathecal space around the spinal cord may reduce the incidence of systemic side effects and allow for more rapid and effective pain relief. We conducted a health technology assessment of intrathecal drug delivery systems (IDDSs) for adults and children with cancer pain, which included an evaluation of effectiveness, safety, cost-effectiveness, the budget impact of publicly funding IDDSs, patient preferences and values, and ethical considerations.

Methods

We performed a systematic literature search of the clinical evidence to retrieve systematic reviews, and we selected and reported results from 2 recent reviews that were relevant to our research questions. We complemented the chosen systematic reviews with a literature search to identify primary studies published after December 2020. We used the Risk of Bias in Systematic Reviews (ROBIS) tool to assess the risk of bias of each included systematic review. We assessed the quality of the body of evidence according to the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) Working Group criteria. We performed a systematic economic literature search and conducted a cost-effectiveness analysis comparing IDDSs with standard care (i.e., non-IDDS methods of pain management) from a public payer perspective. We also analyzed the budget impact of publicly funding IDDSs in Ontario. To contextualize the potential value of IDDSs, we spoke with patients with cancer pain and with caregivers of patients with cancer pain. We explored ethical considerations from a review of published literature on the use of IDDSs for the management of cancer pain in adults and children as well as a review of the other components of this health technology assessment to identify ethical considerations relevant to the Ontario context.

Results

We included 2 systematic reviews (1 on adults and 1 on children) in the clinical evidence review. In adults with cancer pain who have a life expectancy greater than 6 months, intrathecal drug delivery was associated with a significant reduction in pain intensity compared with before implantation up to a 1-year follow-up (GRADE: Moderate to Low). Improved pain management appeared to be maintained beyond a 4-week follow-up. IDDSs likely decrease the use of systemic opioids (GRADE: Moderate to Low). They may also improve health-related quality of life (GRADE: Low), functional outcomes (GRADE: Low), and survival (GRADE: Low to Very low). In children with cancer pain, IDDSs may reduce pain intensity, improve functional outcomes, and improve survival, but the evidence is very uncertain (all GRADEs: Very low). IDDS implantation carries certain rare risks related to mechanical errors, drug-related side effects, and surgical complications. There are inherent limitations in conducting research in patients with refractory cancer pain; therefore, it is unlikely that higher-quality evidence will emerge in the next few years. Our primary economic evaluation found that IDDSs are more effective and more costly than standard care. The incremental cost-effectiveness ratio of IDDSs compared with standard care is $57,314 per quality-adjusted life-year (QALY) gained. The probability of IDDSs being cost-effective versus standard care is 43.46% at a willingness-to-pay of $50,000 per QALY gained and 72.54% at a willingness-to-pay of $100,000 per QALY gained. Publicly funding IDDSs in Ontario would cost an additional $0.27 million per year, for a total of $1.34 million over the next 5 years. The patients with cancer pain and caregivers with whom we spoke described the debilitating nature of cancer pain and the difficulty of finding effective pain management options. Patients with experience of an IDDS spoke of its effectiveness and its positive impact on their quality of life and mental health. Implementing IDDSs for patients with cancer pain raises several ethical and equity considerations related to the experiences and management of cancer pain, how limitations in evidence may entail uncertainties in clinical and health system decision-making, as well as clinical, geographic, and health system access barriers.

Conclusions

Intrathecal drug delivery likely reduces pain intensity and decreases the use of systemic opioids in adults with cancer pain who have a life expectancy greater than 6 months. It may also improve health-related quality of life, functional outcomes, and survival, although the evidence for survival is very uncertain. The clinical evidence in children with cancer pain is very uncertain. IDDS implantation is reasonably safe. Intrathecal drug delivery is more effective and more costly than standard care. We estimate that funding IDDSs in Ontario will result in additional costs of $0.27 million per year, for a total of $1.34 million over the next 5 years. Considerations related to funding and implementing IDDSs for patients with cancer pain in Ontario will require explicit and focused attention to considerations of equity and access in the diagnosis and management of cancer pain and in the use, clinical uptake, and delivery of IDDS pain management.

Differences in efficacy and safety between intrathecal infusion devices in cancer pain

BACKGROUND

Intrathecal infusion therapy is widely accepted for cancer pain patients when conventional analgesic treatments are not sufficient. There are different types of devices for carrying out this therapy: partially externalized devices (PED), used when life expectancy is under 3 months, and totally implanted devices (TID), when it is larger. Our objective is to compare the efficacy, functionality, and complication rate in both types.

METHODS

We included 132 patients with mild-severe cancer pain, treated with intrathecal infusion therapy by fixed flow devices, PED, or TID, during the study time. Demographic, physical oncologic, and pain control data of the patients were recorded prior to starting therapy and at months 1, 3, and 6. Functionality status and complications were also collected from the patient's medical records and clinical files.

RESULTS

Pain control improved after starting therapy, with an overall reduction of 4.75 points in VAS score at 1 month in the both groups, without significant differences between them, keeping it at 3 months and 6. 33.3% of the patients developed complications and were more frequent in the PED group, being catheter dislocation the most common. Patients with TID required more often hospital admission to solve the complication.

CONCLUSIONS

Intrathecal infusion therapy has been shown to be a very effective and safe therapy for the treatment of moderate to severe oncologic pain. There are no significant differences between PED and TID in terms of degree of pain control, therapeutic success, efficacy on episodic or nocturnal pain, or the presence of serious complications.

Predictive factors for efficacy and safety of intrathecal infusion devices for oncological pain

Introduction

In an important percentage of intrathecal infusion therapy, the pain after implantation of a spinal device does not improve. Our objective is to identify factors that can predict therapeutic success and complications, developing a predictive model based on univariate and multivariate analyses.

Methods

Retrospective observational study, including 132 patients with oncological pain who were implanted with a fixed-flow device for intrathecal infusion. Four time points were established for data collection and, in addition to demographic and anthropometric data, variables related to oncologic pain pathology, initiation of therapy, pain control and complications were collected. Based on univariate and multivariate analyses, we performed predictive models on efficacy and complications.

Results

The mean baseline pain intensity was VAS 7.78, and when comparing the values before implantation with those at month 1, we observed an overall decrease of 4.75 points, maintained at months 3 and 6. Nocturnal pain progressively decreased in incidence from 50.0% before implantation to 21.8%, 9.1% and 4.3% at 1, 3 and 6 months. Episodic pain was present in 90.1% of the patients before implantation (7.79 episodes/day), and at 6 months the incidence remained at 53.8%. Most of the patients (66.6%) had no complications related to therapy. We constructed a highly significant multivariate model for the efficacy of the therapy with a predictive capacity of 30.2% and composed of factors: absence of nocturnal pain before implantation and clinical improvement on day 2 after implant. Regarding the prediction of complications, it was not possible to achieve a significantly multivariate effective model.

Conclusion

We identify two factors that predict therapeutic success in a multivariate model: the absence of nocturnal pain before implantation and the improvement of pain on the second day after implantation.

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.

Comparison of external system and implanted system in intrathecal therapy for refractory cancer pain in China: A retrospective study

INTRODUCTION

Intrathecal therapy (ITT) via an implanted system was demonstrated for the treatment of refractory cancer pain for decades. Recently, the dissemination of ITT is enhanced in an external system way in Asia for a lower implantation cost. This study compares the efficacy, safety, and cost of the two ITT systems in refractory cancer pain patients in China.

METHODS

One hundred and thirty-nine cancer pain patients who underwent implantation of the ITT system were included. One hundred and three patients received ITT via the external system (external group), while 36 patients received ITT via the implanted system (implanted group). A 1:2 propensity score matching procedure was used to yield a total of 89 patients for the final analysis. Medical records of included patients were retrospectively reviewed and pain scores, incidences of complications, and costs were compared.

RESULTS

ITT via the external system provided pain relief as potent as ITT via the implanted system but was less time-consuming in the implantation phase (13 vs. 19 days, p < .01). Nausea/vomiting and urinary retention were the most frequent adverse events in both external and implanted groups (32.14%, 16.07% vs. 36.36%, 21.21%). No significant difference was found in the incidences of all kinds of complications. Compared to the implanted group, the external group cost less for the initial implantation (7268 vs. 26,275 US dollar [USD], p < .001) but had a significant higher maintenance cost (606.62 vs. 20.23 USD calculated monthly, p < .001).

CONCLUSIONS

ITT via the external system is as effective and safe as that via the implanted system and has the advantage of being cheap in the upfront implantation but costs more during the maintenance process in China.

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.

The Effect of Measured Radiotherapy Dose on Intrathecal Drug Delivery System Function

OBJECTIVES

Radiation therapy (RT) and intrathecal drug delivery systems (IDDS) are often used concurrently to optimize pain management in patients with cancer. Concern remains among clinicians regarding the potential for IDDS malfunction in the setting of RT. Here we assessed the frequency of IDDS malfunction in a large cohort of patients treated with RT.

MATERIALS AND METHODS

Cancer patients with IDDS and subsequent RT at our institution from 2011 to 2019 were eligible for this study. Patients were excluded in the rare event that their IDDS was managed by an outside clinic and follow-up documentation was unavailable. Eighty-eight patients aged 22-88 years old (43% female, 57% male) representing 106 separate courses of RT were retrospectively identified. Patients received varying levels of radiation for treatment of cancer and cumulative dose to the IDDS was calculated. IDDS interrogation was subsequently performed by a pain specialist. Malfunction was recorded as deviation from the expected drug volume and/or device errors reported upon interrogation as defined by the manufacturer.

RESULTS

Total measured RT dose to the IDDS ranged from 0 to 18.0 Gy (median = 0.2 Gy) with median dose of 0.04 Gy/fraction (range, 0-3.2 Gy/fraction). Ten pumps received a total dose >2 Gy and three received ≥5 Gy. Eighty-two percentage of patients had follow-up with a pain specialist for IDDS interrogation and all patients underwent follow-up with a healthcare provider following RT. There were zero incidences of IDDS malfunction related to RT. No patient had clinical evidence of radiation related pump malfunction at subsequent encounters.

CONCLUSIONS

We found no evidence that RT in patients with IDDS led to device failure or dysfunction. While radiation oncologists and pain specialists should coordinate patient care, it does not appear that RT dose impacts the function of the IDDS to warrant significant clinical concern.

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.

Simultaneous explantation and implantation of intrathecal pumps: a case series

OBJECTIVE

Intrathecal drug delivery devices (IDDDs) are a mainstay in the treatment of spasticity and refractory pain. While these devices have been shown to greatly improve the quality of life for patients, they also have a high perioperative complication and failure rate. A major complication of IDDD implantation is infection. The current standard of care in the treatment of IDDD infection necessitates that the pump be explanted and the infection treated prior to implantation of a new IDDD. This process leads to long hospital stays, interruptions in optimal medical management, and a high risk for dangerous drug withdrawals. The authors describe a technique that allows for the explantation of the infected pump and implantation of a new pump concurrently, which they have named the "Turner Switch" technique in honor of its inventor.

METHODS

The authors conducted a retrospective analysis of cases of infected IDDDs in which patients underwent simultaneous explantation of the infected pump and implantation of a new pump. Demographics and clinical data were collected.

RESULTS

Data from a total of 17 patients (11 male, 6 female) who underwent simultaneous IDDD explantation and implantation to treat infections were analyzed from a 3-year period. No patients experienced infection of the newly implanted pump or catheter. Of the 17 patients, 14 (82.4%) had baclofen pumps to treat spasticity and 3 (17.6%) had fentanyl pumps to treat chronic pain. The median hospital stay was 7 days, with 16 of 17 (94.1%) patients able to be discharged home or to a facility with a level of care similar to their preoperative care. All patients ultimately experienced complete resolution of their initial infections. Five patients (29.4%) required a return to the operating room within the next 5 months (for repair of a CSF leak in 2 cases, for treatment of infection at the old pump site in 2 cases, and for treatment of a CSF leak compounded with infection in 1 case). No patient experienced infection of the newly implanted pump or catheter.

CONCLUSIONS

IDDD infections represent a large portion of morbidity associated with these devices. The current standard of care for deep pump infections requires pump explantation and a course of antibiotics prior to reimplantation of the IDDD. The authors demonstrate the effectiveness of a procedure involving simultaneous explantation of an infected pump and implantation of a new pump on the contralateral side in the treatment of IDDD infections.

Intrathecal Drug Delivery Systems for Cancer Pain: An Analysis of a Prospective, Multicenter Product Surveillance Registry

BACKGROUND

The safety and efficacy of intrathecal drug delivery systems (IDDSs) for the treatment of cancer-related pain have been demonstrated in randomized controlled clinical trials (RCTs). Despite positive evidence for this therapy, IDDS remains underutilized to treat cancer pain. Real-world registry data augment existing safety and effectiveness data and are presented here to broaden awareness of this therapeutic option, needed for adequate cancer-related pain treatment, and as a viable tool addressing concerns with systemic opioid use.

METHODS

This prospective, long-term, multicenter (United States, Western Europe, and Latin America) registry started in 2003 to monitor the performance of SynchroMed Infusion Systems. Patient-reported outcomes were added in 2013. Before data acquisition, all sites obtained Ethics Committee/Institutional Review Board approval and written patient consent. The study was registered (NCT01524276 at clinicaltrials.gov) before patients were enrolled. Patients who provided informed consent were enrolled in the registry at initial IDDS implant or replacement.

RESULTS

Through July 2017, 1403 patients with cancer pain were enrolled and implanted. The average (minimum/maximum) age of patients was 59 years (13/93 years), with 56.6% female. The most frequent cancer types were lung, breast, colon/rectal, pancreatic, and prostate. The majority of patients whose registry follow-up ended (87%; 1141/1311) were followed through death, with 4.3% (n = 57) exiting due to device explant or therapy discontinuation; the remaining 113 (8.6%) discontinued for reasons such as transfer of care, lost to follow-up, and site closure. Pain scores within the cohort of patients providing baseline and follow-up data improved significantly at 6 (P = .0007; n = 103) and 12 (P = .0026; n = 55) months compared to baseline, with EuroQol with 5 dimensions (EuroQol-5D) scores showing significant improvement at 6 months (P = .0016; n = 41). Infection requiring surgical intervention (IDDS explant, replacement, pocket revision, irrigation and debridement, etc) was reported in 3.2% of patients.

CONCLUSIONS

Adequate and improved pain control in patients with cancer, even in advanced stages, with concurrent quality of life maintenance is attainable. Results from this large-scale, multicenter, single-group cohort supplement existing RCT data that support IDDS as a safe and effective therapeutic option with a positive benefit-risk ratio in the treatment of cancer pain.

Scope and Applications of Nanomedicines for the Management of Neuropathic Pain

Neuropathic pain, resulting from the dysfunction of the peripheral and central nervous system, occurs in a variety of pathological conditions including trauma, diabetes, cancer, HIV, surgery, multiple sclerosis, ischemic attack, alcoholism, spinal cord damage, and many others. Despite the availability of various treatment strategies, the percentage of patients achieving adequate pain relief remains low. The clinical failure of most effective drugs is often not due to a lack of drug efficacy but due to the dose-limiting central nervous system (CNS) toxicity of the drugs that preclude dose escalation. There is a need for cross-disciplinary collaborations to meet these challenges. In this regard, the integration of nanotechnology with neuroscience is one of the most important fields. In recent years, promising preclinical research has been reported in this field. This review highlights the current challenges associated with conventional neuropathic pain treatments, the scope for nanomaterials in delivering drugs across the blood-brain barrier, and the state and prospects of nanomaterials for the management of neuropathic pain.

Managing Pain in the Older Cancer Patient

PURPOSE OF REVIEW

This paper aims to give the specialist and non-specialist alike an overview of the considerations involved in the management of cancer-related pain in the older population.

RECENT FINDINGS

Comprehensive guidelines on cancer pain management have been published recently by expert bodies. Cancer pain differs in many respects to other pain conditions and we are likely to encounter it more frequently in older patients in the future. The elderly are more sensitive to the effects of many analgesic medications. The elderly patient with cancer pain presents a unique challenge to the treating physician. The biological effects of ageing impact on the efficacy of many pain management strategies as well as its diagnosis and assessment. Treatment options can be broadly divided into pharmacological, non-pharmacological and interventional. A multidisciplinary approach and frequent re-assessment are essential in achieving favourable outcomes in this patient group.