Intrathecal Analgesia Via a Percutaneous Port For the Management of Movement-Evoked Breakthrough Cancer Pain of Refractory Lower Extremity Cancer Pain: A Retrospective Review and Commentary

Background and Objectives: Intrathecal analgesia (ITA) is a trusty treatment option for refractory and intractable cancer pain. However, there is still no general consensus on the analgesic effect of movement-evoked breakthrough pain (MEBTP) in the ITA setting. This study examined the effect of patient-controlled intrathecal analgesia (PCIA) on analgesic efficacy, emphasizing movement evoked breakthrough pain (MEBTP) in patients with refractory lower extremity cancer pain. Methods: A retrospective chart review included all patients with refractory lower extremity cancer pain who received Intrathecal morphine infusion therapy via percutaneous port (IMITPP) at our hospital between January 2017 and December 2020. Data on the numerical pain rating scales (NRS) scores, opioid doses, and complications were collected from medical records prior to IMITPP and at a one-month postimplant visit.Results: A total of 16 patients were included in the study group. Mean SRPI (spontaneous resting pain intensity) decreased from 8.75 pre- IMITPP to 3.75 post- IMITPP, (P < 0.001); mean MEPI (movement-evoked breakthrough pain intensity) fell from 8.83 pre- IMITPP to 4.25 post- IMITPP (P < 0.001); mean daily morphine equivalent dosing decreased from 360 mg/d to 48mg/d (P< 0.001); mean daily morphine equivalent dosing for MEBTP decreased from 87 mg/d to 6 mg/d (P< 0.001). Both total and breakthrough dosing of conventional opioid medications significantly decreased following the initiation of ITT with PCIA. The mean perceived time to onset with conventional movement evoked breakthrough medications was 38 minutes, and the mean perceived time to onset with PCIA was 8 minutes (P < 0.001). Conclusions: IMITPP was associated with improved pain control in patients with refractory lower extremity cancer pain. Compared with conventional MEBTP medication, appropriate PCIA provided superior analgesia and a much faster onset of action.

Congress of Neurological Surgeons Systematic Review and Evidence-Based Guideline on Neuroablative Procedures for Patients With Cancer Pain

BACKGROUND Managing cancer pain once it is refractory to conventional treatment continues to challenge caregivers committed to serving those who are suffering from a malignancy. Although neuromodulation has a role in the treatment of cancer pain for some patients, these therapies may not be suitable for all patients. Therefore, neuroablative procedures, which were once a mainstay in treating intractable cancer pain, are again on the rise. This guideline serves as a systematic review of the literature of the outcomes following neuroablative procedures. OBJECTIVE To establish clinical practice guidelines for the use of neuroablative procedures to treat patients with cancer pain. METHODS A systematic review of neuroablative procedures used to treat patients with cancer pain from 1980 to April 2019 was performed using the United States National Library of Medicine PubMed database, EMBASE, and Cochrane CENTRAL. After inclusion criteria were established, full text articles that met the inclusion criteria were reviewed by 2 members of the task force and the quality of the evidence was graded. RESULTS In total, 14 646 relevant abstracts were identified by the literature search, from which 189 met initial screening criteria. After full text review, 58 of the 189 articles were included and subdivided into 4 different clinical scenarios. These include unilateral somatic nociceptive/neuropathic body cancer pain, craniofacial cancer pain, midline subdiaphragmatic visceral cancer pain, and disseminated cancer pain. Class II and III evidence was available for these 4 clinical scenarios. Level III recommendations were developed for the use of neuroablative procedures to treat patients with cancer pain. CONCLUSION Neuroablative procedures may be an option for treating patients with refractory cancer pain. Serious adverse events were reported in some studies, but were relatively uncommon. Improved imaging, refinements in technique and the availability of new lesioning modalities may minimize the risks of neuroablation even further. The full guidelines can be accessed at https://www.cns.org/guidelines/browse-guidelines-detail/guidelines-on-neuroablative-procedures-patients-wi.

Intraoperative Neurophysiology for Optimization of Percutaneous Spinothalamic Cordotomy for Intractable Cancer Pain

BACKGROUND Percutaneous ablation of the cervical spinothalamic tract (STT) remains a therapeutic remedy for intractable cancer pain. However, it is accompanied by the risk of collateral damage to essential spinal cord circuitry, including the corticospinal tract (CST). Recent studies describe threshold-based mapping of the CST with the objective of motor bundle preservation during intramedullary spinal cord and supratentorial surgery. OBJECTIVE To assess the possibility that application of spinal cord mapping using intraoperative neuromonitoring in percutaneous cordotomy procedures may aid in minimizing iatrogenic motor tract injury. METHODS We retrospectively reviewed the files of 11 patients who underwent percutaneous cervical cordotomy for intractable oncological pain. We performed quantitative electromyogram (EMG) recordings to stimulation of the ablation needle prior to the STT-ablative stage. We compared evoked motor and sensory electrical thresholds, and the electrical span between them as a reliable method to confirm safe electrode location inside the STT. RESULTS Quantified EMG data were collected in 11 patients suffering from intractable cancer pain. The threshold range for evoking motor activity was 0.3 to 1.2 V. Stimulation artifacts were detected from trapezius muscles even at the lowest stimulation intensity, while thenar muscles were found to be maximally sensitive and specific. The minimal stimulation intensity difference between the motor and the sensory threshold, set as “Δ-threshold,” was 0.26 V, with no new motor deficit at 3 days or 1 month postoperatively. CONCLUSION Selective STT ablation is an effective procedure for treating intractable pain. It can be aided by quantitative evoked EMG recordings, with tailored parameters and thresholds.

Tailoring of neurosurgical ablative procedures in the management of refractory cancer pain

IntroductionNeurosurgical ablative procedures can offer immediate and effective pain relief for patients suffering from refractory cancer pain. However, choosing the appropriate procedure for each patient may not be straightforward and warrants an interdisciplinary approach. The purpose of the current study was to evaluate the outcome of patients with cancer who were carefully selected for neurosurgical intervention by a dedicated interdisciplinary team composed of a palliative physician and nurse practitioner, a pain specialist and a neurosurgeon.MethodsA retrospective review was carried out on all patients who underwent neurosurgical ablative procedures in our institute between March 2015 and September 2019. All patients had advanced metastatic cancer with unfavorable prognosis and suffered from intractable oncological pain. Each treatment plan was devised to address the patients’ specific pain syndromes.ResultsA total of 204 patients were examined by our service during the study period. Sixty-four patients with localized pain and nineteen patients with diffuse pain syndromes were selected for neurosurgical interventions, either targeted disconnection of the spinothalamic tract or stereotactic cingulotomy. Substantial pain relief was reported by both groups immediately (cordotomy: Numerical Rating Scale (NRS) 9 ≥1, p=0.001, cingulotomy: NRS 9 ≥2, p=0.001) and maintained along the next 3-month follow-up visits.ConclusionsAn interdisciplinary collaboration designated to provide neurosurgical ablative procedures among carefully selected patients could culminate in substantial relief of intractable cancer pain.Trial registration numberIR0354-17.

Epidural analgesia for intractable cancer pain - An old story used until now

Intractable cancer pain is a chronic severe pain, affecting patient’s quality of life and presents aheavy health, social and family problem in many countries. Different methods for pain relief are proposed by the WHO. Epidural analgesia with opioids is one of the proposed methods. Aim of the study was to determine the effects of morphine, fentanyl and butorphanol used for epidural analgesia in intractable pain and to comment our experiences over a five-year-period, with regard to its actuality nowadays. Material and methods: Retrospective longitudinal observational study was carried at the University Clinic for Anesthesiology, Reanimation and Intensive Care in Skopje, Macedonia, between 2005-2010 and evaluated in 2017-2018. A total of 116 patients suffering from intractable pain were enrolled in the study. Exclusion criteria were: infective and metastatic processes in the spine, allergy to opioids, psychological problems and language barrier. After the pretreatment evaluation of the pain, patients were randomly assigned to receive three different opioids through epidural catheter placed from Th8-10 or L2-3. Results: There were no differences in pretreatment pain scores between the three groups (p>0.05). A significant onset of analgesia after 15 minutes was found for butorphanol, 20 minutes for fentanyl and 30 minutes for morphine group (p<0.05). The duration of the pain relief of butorphanol vs. fentanyl vs. morphine was 6h vs. 8h vs. 24 hours respectively. Morphine had the longest duration of pain relief (p<0.05). Because of an increase in the pain threshold, the need of an increase of opioid doses was necessary. The most often patient’s reports of side effects were: itching, constipation, urine retention and bradypnea and there were no reports of nausea and vomiting. Conclusions: It was concluded that epidural analgesia with opioids is an effective and safe method for suppression of intractable pain. In spite of the other alternatives in treatment of cancer pain, epidural analgesia with opioids still has an eminent place and its use is a challenge for professionals

Neurosurgical ablative procedures for intractable cancer pain

OBJECTIVECancer patients suffering from severe refractory pain may benefit from targeted ablative neurosurgical procedures aimed to disconnect pain pathways in the spinal cord or the brain. These patients often present with a plethora of medical problems requiring careful consideration before surgical interventions. The authors present their experience at an interdisciplinary clinic aimed to facilitate appropriate patient selection for neurosurgical procedures, and the outcome of these interventions.METHODSThis study was a retrospective review of all patients who underwent neurosurgical interventions for cancer pain in the authors’ hospital between March 2015 and April 2018. All patients had advanced metastatic cancer with limited life expectancy and suffered from intractable oncological pain.RESULTSSixty patients underwent surgery during the study period. Forty-three patients with localized pain underwent disconnection of the spinal pain pathways: 34 percutaneous-cervical and 5 open-thoracic cordotomies, 2 stereotactic mesencephalotomies, and 2 midline myelotomies. Thirty-nine of 42 patients (93%) who completed these procedures had excellent immediate postoperative pain relief. At 1 month the improvement was maintained in 30/36 patients (83%) available for follow-up. There was 1 case of hemiparesis.Twenty patients with diffuse pain underwent stereotactic cingulotomy. Nineteen of these patients reported substantial pain relief immediately after the operation. At 1 month good pain relief was maintained in 13/17 patients (76%) available for follow-up, and good pain relief was also found at 3 months in 7/11 patients (64%). There was no major morbidity or mortality.CONCLUSIONSWith careful patient selection and tailoring of the appropriate procedure to the patient’s pain syndrome, the authors’ experience indicates that neurosurgical procedures are safe and effective in alleviating suffering in patients with intractable cancer pain.

Cordotomy for Intractable Cancer Pain: A Narrative Review

Background: Cordotomy is an invasive procedure for the management of intractable pain not controlled by conventional therapies, such as analgesics or nerve block. This procedure involves mechanical disruption of nociceptive pathways in the anterolateral column, specifically the spinothalamic and spinoreticular pathways to relieve pain while preserving fine touch and proprioceptive tracts. Objectives: The purpose of this review article is to refresh our knowledge of cordotomy and support its continued use in managing intractable pain due to malignant disease. Study Design: This is a review article with the goal of reviewing and summarizing the pertinent case reports, case series, retrospective studies, prospective studies, and review articles published from 2010 onward on spinal cordotomy. Setting: The University of Texas, MD Anderson Cancer Center. Methods: PubMed search of keywords “spinal cordotomy,” “percutaneous cordotomy,” or “open cordotomy” was undertaken. Search results were organized by year of publication. Results: Cordotomy can be performed via percutaneous, open, endoscopic, or transdiscal approach. Percutaneous image-guided approach is the most well-studied and reported technique compared with others, with relatively good pain improvement both in the postoperative and shortterm period. The use of open cordotomy has diminished significantly in recent years because of the advent of other less invasive approaches. Cordotomy in children, although rare, has been described in some case reports and case series with reported pain improvement postprocedure. Although complications can vary broadly, some reported side effects include ataxia and paresis due to lesion in the spinocerebellar/corticospinal tract; respiratory failure due to lesion in the reticulospinal tract; or sympathetic dysfunction, bladder dysfunctions, or Horner syndrome due to unintentional lesions in the spinothalamic tract. Limitations: Review article included literature published only in English. For the studies reviewed, the sample size was relatively small and the patient population was heterogeneous (in terms of underlying disease process, duration of symptoms, previous treatment attempted and length of follow-up). Conclusions: Cordotomy results in selective loss of pain and temperature perception on the contralateral side, up to several segments below the level of the disruption. The plethora of analgesics available and advanced technologies have reduced the demand for cordotomy in the management of intractable pain. However, some patients with pain unresponsive to medical and procedural management, particularly malignant pain, may benefit from this procedure, and it is a viable treatment option especially for patients with a limited life expectancy whose severe, unilateral pain is unresponsive to analgesic medications. Key words: Cancer pain, cordotomy complications, cordotomy indications, intractable pain, open cordotomy, percutaneous cordotomy

Magnetic Resonance-Based Radiomic Analysis of Radiofrequency Lesion Predicts Outcomes After Percutaneous Cordotomy: A Feasibility Study

BACKGROUND To date, there is limited data on evaluation of the cordotomy lesion and predicting clinical outcome. OBJECTIVE To evaluate the utility of magnetic resonance (MR)-based radiomic analysis to quantify microstructural changes created by the cordotomy lesion and predict outcome in patients undergoing percutaneous cordotomy for medically refractory cancer pain. METHODS This is a retrospective interpretation of prospectively acquired data in 10 patients (5 males, age range 43-76 yr) who underwent percutaneous computed tomography-guided high cervical cordotomy for medically refractory cancer pain between 2015 and 2016. All patients underwent magnetic resonance imaging (MRI) of the cordotomy lesion on postoperative day 1. After segmentation of T2-weighted images, 310 radiomic features were extracted. Pain outcomes were recorded on postoperative day 1 and day 7 using the visual analog scale. R software was used to build statistical models based on MRI radiomic features for prediction of pain outcomes. RESULTS A total of 20 relevant radiomic features were identified using the maximum relevance minimum redundanc method. Radiomics predicted postoperative day 1 pain scores with an accuracy of 90% (P = .046), 100% sensitivity, 75% specificity, 85.7% positive predictive value, and 100% negative predictive value. The radiomics model also predicted if the postoperative day 1 pain score was sustained on postoperative day 7 with an accuracy of 100% (P = .028), 100% sensitivity, 100% specificity, and 100% positive and negative predictive value. CONCLUSION MR-based radiomic analysis of the cordotomy lesion was predictive of pain outcomes at 1 wk after percutaneous cordotomy for intractable cancer pain.