The incidence of neuropathic pain in bone metastases patients referred for palliative radiotherapy

Epigenetic mechanisms of bone cancer pain

The management and treatment of bone cancer pain (BCP) remain significant clinical challenges, imposing substantial economic burdens on patients and society. Extensive research has demonstrated that BCP induces changes in the gene expression of peripheral sensory nerves and neurons, which play crucial roles in the onset and maintenance of BCP. However, our understanding of the epigenetic mechanisms of BCP underlying the transcriptional regulation of pro-nociceptive (such as inflammatory factors and the transient receptor potential family) and anti-nociceptive (such as potassium channels and opioid receptors) genes remains limited. This article reviews the epigenetic regulatory mechanisms in BCP, analyzing the roles of histone modifications, DNA methylation, and noncoding RNAs (ncRNAs) in the expression of pro-nociceptive and anti-nociceptive genes. Finally, we provide a comprehensive view of the functional mechanisms of epigenetic regulation in BCP and explore the potential of these epigenetic molecules as therapeutic targets for BCP.

Understanding the initiation, delivery and processing of bone cancer pain from the peripheral to the central nervous system

Bone cancer pain is a complex condition characterized by persistent, sudden, spontaneous pain accompanied by hyperalgesia that typically arises from bone metastases or primary bone tumors, causing severe discomfort and significantly diminishing cancer patients' quality of life and confidence in their ability to overcome the disease. It is widely known that peripheral nerves are responsible for detecting harmful stimuli, which are then transmitted to the brain via the spinal cord, resulting in the perception of pain. In the case of bone cancer, tumors and stromal cells within the bone marrow release various chemical signals, including inflammatory factors, colony-stimulating factors, chemokines, and hydrogen ions. Consequently, the nociceptors located at the nerve endings within the bone marrow sense these chemical signals, generating electrical signals that are then transmitted to the brain through the spinal cord. Subsequently, the brain processes these electrical signals in a complex manner to create the sensation of bone cancer pain. Numerous studies have investigated the transmission of bone cancer pain from the periphery to the spinal cord. However, the processing of pain information induced by bone cancer within the brain remains unclear. With the continuous advancements in brain science and technology, the brain mechanism of bone cancer pain would become more clearly understood. Herein, we focus on summarizing the peripheral nerve perception of the spinal cord transmission of bone cancer pain and provide a brief overview of the ongoing research regarding the brain mechanisms involved in bone cancer pain.

Update on Prevalence of Pain in Patients with Cancer 2022: A Systematic Literature Review and Meta-Analysis

Experiencing pain and insufficient relief can be devastating and negatively affect a patient's quality of life. Developments in oncology such as new treatments and adjusted pain management guidelines may have influenced the prevalence of cancer pain and severity in patients. This review aims to provide an overview of the prevalence and severity of pain in cancer patients in the 2014-2021 literature period. A systematic literature search was performed using the databases PubMed, Embase, CINAHL, and Cochrane. Titles and abstracts were screened, and full texts were evaluated and assessed on methodological quality. A meta-analysis was performed on the pooled prevalence and severity rates. A meta-regression analysis was used to explore differences between treatment groups. We identified 10,637 studies, of which 444 studies were included. The overall prevalence of pain was 44.5%. Moderate to severe pain was experienced by 30.6% of the patients, a lower proportion compared to previous research. Pain experienced by cancer survivors was significantly lower compared to most treatment groups. Our results imply that both the prevalence of pain and pain severity declined in the past decade. Increased attention to the assessment and management of pain might have fostered the decline in the prevalence and severity of pain.

Neurophysiological mechanisms of cancer-induced bone pain

Background

Cancer-induced Bone Pain (CIBP) is an important factor affecting their quality of life of cancer survivors. In addition, current clinical practice and scientific research suggest that neuropathic pain is a representative component of CIBP. However, given the variability of cancer conditions and the complexity of neuropathic pain, related mechanisms have been continuously supplemented but have not been perfected.

Aim of Review

Therefore, the current review highlights the latest progress in basic research on the field and proposes potential therapeutic targets, representative drugs and upcoming therapies.

Key Scientific Concepts of Review

Notably, factors such as central sensitization, neuroinflammation, glial cell activation and an acidic environment are considered to be related to neuropathic pain in CIBP. Nonetheless, further research is needed to ascertain the mechanism of CIBP in order to develop highly effective drugs. Moreover, more attention needs to be paid to the care of patients with advanced cancer.

Glycosides for Peripheral Neuropathic Pain: A Potential Medicinal Components

Neuropathic pain is a refractory disease that occurs across the world and pharmacotherapy has limited efficacy and/or safety. This disease imposes a significant burden on both the somatic and mental health of patients; indeed, some patients have referred to neuropathic pain as being 'worse than death'. The pharmacological agents that are used to treat neuropathic pain at present can produce mild effects in certain patients, and induce many adverse reactions, such as sedation, dizziness, vomiting, and peripheral oedema. Therefore, there is an urgent need to discover novel drugs that are safer and more effective. Natural compounds from medical plants have become potential sources of analgesics, and evidence has shown that glycosides alleviated neuropathic pain via regulating oxidative stress, transcriptional regulation, ion channels, membrane receptors and so on. In this review, we summarize the epidemiology of neuropathic pain and the existing therapeutic drugs used for disease prevention and treatment. We also demonstrate how glycosides exhibit an antinociceptive effect on neuropathic pain in laboratory research and describe the antinociceptive mechanisms involved to facilitate the discovery of new drugs to improve the quality of life of patients experiencing neuropathic pain.

The role of the Consultant Radiographer in facilitating rapid access to palliative radiotherapy

INTRODUCTION

The fast track pathway for palliative radiotherapy was created to facilitate rapid access to radiotherapy for symptom relief and improved quality of life. The fast track pathway has a target of 5 days from the decision to treat to starting treatment.

METHODS

This study is a quantitative analysis of all patients referred and treated with palliative radiotherapy between the 1st September 2018 and 30th September 2019. The number of working days overall from referral to treatment and at each stage of the radiotherapy pathway was recorded and evaluated. The electronic referral system was amended to include the treatment priority option of 'fast track' for all patients with the selected treatment intent of 'palliative'. The data was acquired using the electronic referral system reporting tool.

RESULTS

Results demonstrate a reduction in average pathway timing from 14 days to 3 days for volume planned patients, and 13 days to 2 days for virtual simulation patients referred into the fast track pathway. The routine priority palliative pathway also demonstrated a decrease in time from decision to treat to treatment, despite this not being an initial objective.

CONCLUSION

Reducing pathway time from referral to treatment is achievable through the introduction of a fast track treatment priority pathway. Rapid access to treatment was facilitated through the electronic referral system fast track option, the creation of a separate fast track care path in Aria, the use of fast track alerts in Aria, and reserved planning scan and treatment appointments.

IMPLICATIONS FOR PRACTICE

Rapid access to palliative radiotherapy facilitates alleviation of symptoms and improved quality of life. To improve the efficiency of the palliative radiotherapy service, a streamlined pathway and the commitment of the radiotherapy team is required.

Pain response and quality of life assessment in patients with moderate/severe neuropathic pain due to bone metastasis undergoing treatment with palliative radiotherapy and tapentadol: A prospective multicentre pilot study

INTRODUCTION

To assess pain response rate (RR) and quality of life (QoL), in patients with moderate/severe neuropathic pain (NP) due to bone metastasis (BM) undergoing palliative 3D radiotherapy plus tapentadol.

METHODS

We conducted a prospective multicentre pilot study. Patients were assessed before radiotherapy using the validated questionnaire (Douleur Neuropathique en 4 questions). Response to radiotherapy (8 Gy-30 Gy/1-10fr) at one and two months was assessed according the International Bone Metastases Consensus criteria.

INCLUSION CRITERIA

radiological evidence of BM, NP according to DN4 (cut-off score ≥ 4), no spinal cord compression, worst pain score ≥ 5/10. Nonparametric Mann-Whitney U test compared changes in QoL among response groups.

RESULTS

Seventeen patients (13 men, 4 woman), median age 67 years (42-81), were included. Pre-treatment median pain severity was 7.5 (5-10). Median dose of tapentadol administered before radiotherapy was 100 mg/24 h (100-300 mg). Overall RR 1 month after radiotherapy was 10/16 = 62.5%: 3/16 (18.8%) achieving a complete response (CR) and 7/16 (43.8%) a partial response (PR). Overall RR 2 months after RT was 5/10 (50%): 10% a CR and 40% a PR. ITT RR for this study at 1 and 2 months was 10/17 = 59% and 5/17 = 29%, respectively. Patients responding to radiotherapy had significant improvement in EORTC QLQ-C30 emotional functioning (EF) (p = 0.025) and fatigue symptom scale scores (p = 0.035) one month after radiotherapy. Painful site symptom QLQ-BM22 scores improved 2 months after radiotherapy (p = 0.024).

CONCLUSIONS

Palliative radiotherapy plus tapentadol shows an acceptable pain response and QoL improvement especially regarding EF, fatigue and painful site symptom scales in patients with moderate/severe NP due to BM. Therefore, it could be an alternative to manage NP in daily practice.

Which factors can aid clinicians to identify a risk of pain during the following month in patients with bone metastases? A longitudinal analyses

PURPOSE

Explore clinical factors associated with higher pain intensity and future pain in patients with bone metastases to identify patients who can benefit from closer follow-up or pain-modifying interventions.

METHODS

This is a secondary analysis of 606 patients with bone metastases included in a multicenter longitudinal study. The dependent variables were "average pain" and "worst pain" in the last 24 h (0-10 NRS). Twenty independent variables with potential association to pain intensity were selected based on previous literature. Cross-sectional analyses were performed with multiple linear regression to explore factors associated with pain intensity at baseline. Longitudinal data were analyzed with a generalized equation models to explore current factors associated with pain intensity at the next visit in 1 month.

RESULTS

Current pain intensity (p < 0.001), sleep disturbances (p 0.01 and 0.006), drowsiness (p 0.003 and 0.033) and male gender (p 0.045 and 0.001) were associated with higher average and worst pain intensity in 1 month. In addition, breakthrough pain was related to higher worst pain intensity (p 0.003) in 1 month. The same variables were also associated with higher average pain intensity at baseline.

CONCLUSION

Higher current pain intensity, sleep disturbances, drowsiness, male gender, and breakthrough pain are factors associated with higher pain intensity in patients with bone metastases at the next follow-up in 1 month. These factors should be assessed in clinical practice and may aid clinicians in identifying patients that can benefit from closer follow-up or interventions to prevent lack of future pain control. TRIAL REGISTRATION IN CLINICALTRIALS.GOV : NCT01362816.

Patient-reported neuropathic pain in adolescent and young adult cancer patients

BACKGROUND

Neuropathic pain, a known complication of cancer and its treatments, negatively impacts quality of life. There are limited data using screening tools to aid in the diagnosis of neuropathic pain in cancer patients. Our primary objective was to determine the proportion of adolescent and young adult cancer patients reporting neuropathic pain on a patient-completed, neuropathic pain screening tool.

PROCEDURES

This prospective, cohort study enrolled patients 14-39 years of age who were receiving therapy for primary cancer diagnosis, cancer relapse, or had recently completed treatment. The painDETECT, a patient-completed, neuropathic pain screening tool used down to age 14, was administered a maximum of three times in on-therapy patients and once in off-therapy patients. Provider documentation of neuropathic pain at the corresponding visit was abstracted from the medical record.

RESULTS

Seventy-eight patients participated. Median (interquartile range) age at study enrollment was 18.1 (16-19.4) years and 47% were female. Cancer diagnoses included 41% leukemia, 26% solid tumor, 23% lymphoma, and 10% central nervous system tumor. The proportion of patients reporting neuropathic pain was 26% (95% confidence interval [CI] 16-40%) in on-therapy patients and 11% (95% CI 3-27%) in off-therapy patients. In patients reporting neuropathic pain, only 26% had a clinical diagnosis of neuropathic pain documented in the medical record at the corresponding visit.

CONCLUSIONS

Neuropathic pain occurs in one in four adolescents and young adults receiving cancer therapy. Use of screening tools may increase the detection of neuropathic pain in adolescents and young adults receiving cancer therapy and could ultimately improve pain treatment.