Difficult Pain Syndromes

Efficacy of Multidisciplinary Pain Management for Advanced Cancer Patients

OBJECTIVES

The objective of this study is to assess the efficacy and affecting factors of a multidisciplinary team (MDT) on cancer-related pain in patients with advanced cancer.

METHODS

A retrospective analysis was performed on patients receiving pain management from November 2018 to December 2023 by the MDT. Pain intensity, pain management index (PMI), pain response, and Barthel index of activities of daily living (BADL) were assessed at baseline and/or after 2 weeks of MDT interventions. Univariate and multiple logistic analyses were conducted to identify risk indicators for pain response.

RESULTS

After interventions, pain intensity, numerical rating scale (NRS) scores, and PMI significantly improved in all patients (p < .001). Subgroup analyses revealed that pain intensity and NRS scores were notably reduced, while PMI increased after the interventions in the responders (p < .001). Conversely, no significant changes were observed in pain intensity, NRS scores, or PMI for the nonresponders following MDT intervention. MDT interventions did not lead to improvements in BADL for either group. Patients who underwent radiotherapy exhibited a significantly higher overall response rate (ORR) compared to those without radiotherapy (100% vs 60.8%, p = .033). In univariate analysis, lower KPS scores and visceral pain showed negative associations with pain response. However, in multivariate analysis, neither maintained significance.

CONCLUSIONS

The pain MDT demonstrated remarkable improvements in clinical management and pain control. Further prospective studies are warranted to investigate predictive factors associated with pain treatment.

Low-dose add-on methadone for cancer pain management: a retrospective analysis of 102 Japanese patients

BACKGROUND

Methadone was introduced in 2013 for the treatment of intractable cancer pain in Japan and is indicated for patients receiving opioid doses ≧60 mg/day as an oral morphine equivalent. Low-dose (≦10 mg/day) add-on methadone to prior opioids has been reported from European countries to successfully relieve various types of intractable cancer pain; however, there are few reports of such use in Japan. The aim of this study was to analyze more than a hundred cases with low-dose add-on methadone to treat intractable pain in Japanese cancer patients.

METHODS

All cases in which 5 or 10 mg/day of methadone was added to prior opioids by the Palliative Care Team or Division of Palliative Medicine in our hospital during the period between April 2016 and September 2023 were extracted and analyzed retrospectively on electrical medical charts.

RESULTS AND CONCLUSIONS

A total of 102 cases were extracted with a male-to-female ratio of 60:42, and the age (mean ± SD) was 62.8 ± 14.7 years old. Methadone was introduced in an inpatient setting to 86 patients. The major pathologies that caused intractable pain were spinal metastases in 48, pelvis or pelvic floor lesions in 29 and pleural and/or chest wall lesions in 16. The most common mechanism of pain was the mixture of somatic and neuropathic components. The major opioids administered prior to methadone included tapentadol in 46 patients, hydromorphone in 36 and oxycodone in 19. The dose of the prior opioids [median, (interquartile range: IQR)] was 97, (62.8-167.3) (range: 15-1313) mg/day of oral morphine equivalent. Radiotherapy, chemotherapy and nerve blocks were performed as concomitant therapies in 48, 22 and 11 patients, respectively (with some overlap). The number of rescue doses [median (IQR)] was significantly decreased from three (two to five) on the day before methadone to one (zero to four) after seven days from methadone initiation. The side effects leading to discontinuation of methadone were drowsiness in three cases, nausea in three cases and dizziness in one case (with some overlap). Compared with complete switching from other opioids, low-dose add-on methadone can reduce the possibility of major dose discrepancies and can be quickly adjusted by combined opioid reduction/increase. Low-dose add-on methadone can be an effective and safe method for intractable cancer pain.

Defining Spine Cancer Pain Syndromes: A Systematic Review and Proposed Terminology

STUDY DESIGN

Systematic Review.

OBJECTIVES

Formalized terminology for pain experienced by spine cancer patients is lacking. The common descriptors of spine cancer pain as mechanical or non-mechanical is not exhaustive. Misdiagnosed spinal pain may lead to ineffective treatment recommendations for cancer patients.

METHODS

We conducted a systematic review of pain terminology that may be relevant to spinal oncology patients. We provide a comprehensive and unbiased summary of the existing evidence, not limited to the spine surgery literature, and subsequently consolidate these data into a practical, clinically relevant nomenclature for spine oncologists.

RESULTS

Our literature search identified 3515 unique citations. Through title and abstract screening, 3407 citations were excluded, resulting in 54 full-text citations for review. Pain in cancer patients is typically described as nociceptive pain (somatic vs visceral), neurologic pain and treatment related pain.

CONCLUSIONS

We consolidate the terminology used in the literature and consolidated into clinically relevant nomenclature of biologic tumor pain, mechanical pain, radicular pain, neuropathic pain, and treatment related pain. This review helps standardize terminology for cancer-related pain which may help clinicians identify pain generators.

High mobility group box-1: A therapeutic target for analgesia and associated symptoms in chronic pain

The number of patients with chronic pain continues to increase against the background of an ageing society and a high incidence of various epidemics and disasters. One factor contributing to this situation is the absence of truly effective analgesics. Chronic pain is a persistent stress for the organism and can trigger a variety of neuropsychiatric symptoms. Hence, the search for useful analgesic targets is currently being intensified worldwide, and it is anticipated that the key to success may be molecules involved in emotional as well as sensory systems. High mobility group box-1 (HMGB1) has attracted attention as a therapeutic target for a variety of diseases. It is a very unique molecule having a dual role as a nuclear protein while also functioning as an inflammatory agent outside the cell. In recent years, numerous studies have shown that HMGB1 acts as a pain inducer in primary sensory nerves and the spinal dorsal horn. In addition, HMGB1 can function in the brain, and is involved in the symptoms of depression, anxiety and cognitive dysfunction that accompany chronic pain. In this review, we will summarize recent research and discuss the potential of HMGB1 as a useful drug target for chronic pain.

Myofascial component of cancer pain review

BACKGROUND

Pain is a common complaint of cancer patients, experienced by 38%-85% of patients. Some studies have shown a high incidence of myofascial pain syndrome (MPS) in cancer patients.

AIMS

1) To estimate the prevalence of MPS in cancer patients; 2) to examine the efficacy of current treatment options for MPS in cancer patients.

METHODS

Narrative review. PubMed, CINAHL, PEDro, and Google Scholar databases were searched from inception until November 2017, for the keywords: cancer; cancer pain; breast cancer; mastectomy; lumpectomy; myofascial pain; trigger points. Trials of any methodological quality were included. All published material with an emphasis on randomized control trials was analyzed.

RESULTS

MPS is prevalent in cancer patients who suffer from pain, with a prevalence of between 11.9% and 44.8% in those diagnosed either with neck or head or breast cancer. Clinical studies showed conflicting results. Four interventional studies found that specific treatment for MPS may reduce the prevalence of active myofascial trigger points and therefore decrease pain level, sensitivity, and improve range of motion (in shoulder) in cancer patients. Two recent randomized control trials showed that pressure release of trigger points provides no additional beneficial effects to a standard physical therapy program for upper limb pain and function after breast cancer surgery.

CONCLUSIONS

We recommend including the evaluation of myofascial pain in routine clinical examination of cancer patients suffering from pain. Future studies are needed to investigate the long- and short-term effect of MPS treatments in cancer patients.

Underlying Adenocarcinoma of the Lung Metastasizing to the Proximal Phalanx of the Foot Causing Complex Regional Pain SyndromeA Case Report

We report an unusual case of adenocarcinoma of the lung metastasizing to the proximal phalanx of the third digit in a 56-year-old woman with overlying complex regional pain syndrome. The patient was initially treated for neuroma, fracture, and neuropathic pain with no improvement over a 4-month period before presenting to the emergency department for left third digit pain. Radiographic imaging showed substantial osteopenia and mottling; magnetic resonance imaging demonstrated an aggressive lesion to the proximal phalanx. The patient underwent excision of the lesion, revealing metastatic moderately differentiated adenocarcinoma.

Characteristics and prognostic factors for pain management in 152 patients with lung cancer

OBJECTIVE

The objective of this study was to analyze the pain characteristics and factors influencing the outcome of pain control in patients with lung cancer having pain.

METHODS

Pain characteristics, the effectiveness, and prognostic factors for pain control were analyzed in 152 patients with lung cancer having moderate or severe chronic pain admitted to Cancer Center of The First Hospital of Jilin University, People's Republic of China, between January 2012 and May 2013. Information about sex, age, pathological type, TNM stage, presence/absence of bone metastases, characteristics of pain, methods, and effectiveness of pain management was recorded.

RESULTS

Patients with non-small-cell lung cancer and small-cell carcinoma accounted for 132/152 (86.8%) and 20/152 (13.2%) cases, respectively. Among them, moderate (72.4%) or severe pain (27.6%) was reported in 73.7% of the cases at stage IV, chest or back pain was reported in 76.3% of the cases, and pain in other locations in the rest of the cases. Bone metastases were apparent in 44.1% of the patients. Neuropathic pain was noted in 46.7% of the patients, and frequent breakthrough pain was noted in 25.7% of the patients. High pain intensity was associated with frequent breakthrough pain. Pain was adequately controlled in 81.6% of the patients prescribed 3 days of analgesics. More patients reported a KPS higher than or equal to 80 after 3 days of analgesic treatment (P<0.001). Severe pain, frequent breakthrough pain, and presence of bone metastases were independent risk factors for poor pain control. Severe pain, frequent breakthrough pain, or neuropathic pain in the patients using opioids required higher doses of analgesic for pain control. Opioids plus nonsteroidal anti-inflammatory drugs offered better pain control than opioids alone.

CONCLUSION

High pain intensity is associated with frequent breakthrough pain in patients with lung cancer, which can be largely controlled with analgesics. Severe pain, frequent breakthrough pain, presence of bone metastases, and neuropathic pain are predictors of refractory pain.

Meta-Analysis of Massage Therapy on Cancer Pain

Cancer pain is the most common complaint among patients with cancer. Conventional treatment does not always relieve cancer pain satisfactorily. Therefore, many patients with cancer have turned to complementary therapies to help them with their physical, emotional, and spiritual well-being. Massage therapy is increasingly used for symptom relief in patients with cancer. The current study aimed to investigate by meta-analysis the effects of massage therapy for cancer patients experiencing pain. Nine electronic databases were systematically searched for studies published through August 2013 in English, Chinese, and Korean. Methodological quality was assessed using the Physiotherapy Evidence Database (PEDro) and Cochrane risk-of-bias scales. Twelve studies, including 559 participants, were used in the meta-analysis. In 9 high-quality studies based on the PEDro scale (standardized mean difference, −1.24; 95% confidence interval, −1.72 to −0.75), we observed reduction in cancer pain after massage. Massage therapy significantly reduced cancer pain compared with no massage treatment or conventional care (standardized mean difference, −1.25; 95% confidence interval, −1.63 to −0.87). Our results indicate that massage is effective for the relief of cancer pain, especially for surgery-related pain. Among the various types of massage, foot reflexology appeared to be more effective than body or aroma massage. Our meta-analysis indicated a beneficial effect of massage for relief of cancer pain. Further well-designed, large studies with longer follow-up periods are needed to be able to draw firmer conclusions regarding the effectiveness.

Chemotherapy-Induced Peripheral Neuropathy in Pediatric Cancer Patients

Chemotherapy-induced peripheral neuropathies (CIPNs) are an increasingly common neuropathic and pain syndrome in adult and pediatric cancer patients and survivors [1-69]. However, symptoms associated with CIPNs are often undiagnosed, under-assessed, and communications problems between clinicians, family members, and patients have been observed [70-73]. Less is known about the prevalence and impact of CIPNs on pediatric cancer populations [70-71]. This article aims to provide a brief understanding of CIPNs in pediatric populations, and to review the evidence for both its prevention and treatment.

Pain, neuropathic symptoms, and physical and mental well-being in persons with cancer

BACKGROUND

Neuropathic pain is present in at least 25-40% of people with cancer pain and is thought to be more difficult to control than other types of cancer related pain.

OBJECTIVE

The purpose of this study was to explore differences in the experience of cancer patients who describe their pain using neuropathic descriptors compared to those who do not.

METHODS

A secondary analysis of data from 234 outpatients from a large NCI designated cancer center in west, central Florida was conducted to identify differences in pain, pain interference, symptoms, health related quality of life, and depression between the two groups.

RESULTS

Patients with numbness, tingling, or electric-like sensations reported higher levels of current pain (p= .001), pain at its worst (p= .001), pain on average (p= .019), pain at its least (p= .008), and pain interference (p< .001). They reported problems with dizziness/lightheadedness significantly more often (p=.004) and also reported more severe problems with concentration (p=.047), poorer physical (p=.019) and mental health (p=.024), although no differences in depressive symptoms were found.

CONCLUSIONS

The results of this study indicate that cancer patients with numbness, tingling, or electric-like sensations have significantly higher levels of pain and pain interference, and lower health related quality of life than do patients without these symptoms.

IMPLICATIONS FOR PRACTICE

These results highlight the ongoing need for research evaluating methods of treating neuropathic pain; education regarding assessment and management of neuropathic pain; and aggressive efforts to relieve neuropathic pain in oncology settings.

Preliminary assessment of a neuropathic pain treatment and referral algorithm for patients with cancer

CONTEXT

The purpose of this case series study was to pilot test an evidence-based neuropathic pain (NP) treatment and referral algorithm for use by oncology nurses when managing cancer-related NP.

OBJECTIVES

The primary study objective was to assess patient-reported outcomes (pain severity, changes in activities of daily living, and satisfaction) resulting from algorithm use.

METHODS

Outpatients (n=20) with cancer-related NP scores ≥4 on a 0-10 numeric rating scale participated in the study. NP assessment, treatment, and referral to ancillary providers were guided by an evidence-based NP algorithm that was implemented by oncology nurse practitioners. Based on efficacy evidenced through randomized clinical trials published at the time of study implementation, the following drugs were included in the algorithm: lidocaine patch, gabapentin, oxycodone, tramadol, morphine, methadone, duloxetine, pregabalin, and nortriptyline. Recommendations for starting dose, dose escalation, drug combinations, treatment duration, and contraindications were included for first-tier drugs. Patient-reported outcomes (pain severity, functional capacity, and satisfaction) were assessed monthly over 12 weeks.

RESULTS

Average NP severity (P=0.001), general activity (P<0.001), mood (P=0.002), walking ability (P=0.01), ability to perform normal work (P=0.002), relationships (P=0.002), sleep (P=0.01), life enjoyment (P<0.001), and patient satisfaction (P=0.003) all improved by 12 weeks.

CONCLUSION

Evidence from this pilot study suggests that NP evidence-based treatment may result in improved symptoms, function, and patient satisfaction. A randomized controlled trial is needed to further assess algorithm efficacy.

Efficacy of oxycodone/paracetamol for patients with bone-cancer pain: a multicenter, randomized, double-blinded, placebo-controlled trial

WHAT IS KNOWN AND OBJECTIVE

Bone-cancer pain is a common and refractory cancer pain. Opioids, on their own, do not control this type of pain well enough, and co-analgesics are necessary.

METHODS

Patients with bone metastasis-related pain at Numeric Rating Scale ≥4 were enrolled to this randomized placebo-controlled trial. They had also received morphine or transdermal fentanyl patches for at least 1 week. During the 3-day efficacy phase, patients received placebo or 1-3 tablets of oxycodone/paracetamol (5/325 mg), four times daily for 3 days. All patients kept a daily pain diary. The primary endpoint was the Pain Intensity Difference (PID). Secondary endpoints were cases of breakthrough pain and rescue morphine consumption. Additional analyses included the Short Form-6 Dimensions (SF-6D) quality-of-life scale and a general impression (GI) of patient satisfaction with treatment at the end of the phase.

RESULTS AND DISCUSSION

Of the 246 patients in the intent-to-treat set, 89·4% completed the 3-day efficacy phase. PIDs were 0·9 and 0·3 in the oxycodone/paracetamol and placebo groups respectively, on day 1 (P < 0·001), and 1·5 and 0·3 respectively on day 3 (P < 0·001). Thirty-eight patients in the treatment group, and 58 in the placebo group, suffered breakthrough pain on day 3 (P < 0·001). The SF-6D score decreased to 21·2 ± 2·5 in the oxycodone/paracetamol group at the end of the phase (P = 0·001). In the oxycodone/paracetamol group, 67% rated GI as good, very good, or excellent.

WHAT IS NEW AND CONCLUSION

Patients with bone-cancer pain, already on opioids, obtain clinically important, additional pain-control, with regular oxycodone/paracetamol dosing.

Comparison of oxaliplatin- and cisplatin-induced painful peripheral neuropathy in the rat

Although platinum-based cancer chemotherapies produce painful peripheral neuropathy as dose-limiting side effects, there are important differences in the pain syndromes produced by members of this class of drugs. In the rat, cisplatin-induced hyperalgesia has latency to onset of 24 to 48 hours, is maximal by 72 to 96 hours, and is attenuated by inhibitors of caspase signaling but not by inhibitors of the mitochondrial electron transport chain (mETC) and antioxidants. In contrast, oxaliplatin-induced mechanical hyperalgesia is already present by 5 minutes and peaks by 20 minutes. Whereas oxaliplatin hyperalgesia persists for weeks, starting around day 10 to 15, its severity decreases to a lower 2nd plateau level. The rapid-onset 1st plateau in oxaliplatin-induced hyperalgesia was characterized by prominent cold allodynia and in contrast to cisplatin was attenuated by inhibitors of the mETC and antioxidants but not inhibitors of caspase signaling. However, tested later during the 2nd plateau, it was characterized by less intense hyperalgesia and no cold allodynia and was attenuated by inhibitors of caspase signaling as well as by inhibitors of the mETC and by antioxidants.

PERSPECTIVE

The findings of this study distinguish between the neuropathic pain syndromes produced by members of a single chemical class of anticancer drugs and suggest that the underlying mechanisms of various forms of peripheral neuropathy may be different. Further, it defines the need for selective therapy for different types of neuropathy.