Towards precision pain medicine for pain after cancer: the Cancer Pain Phenotyping Network multidisciplinary international guidelines for pain phenotyping using nociplastic pain criteria

"How Do You Live the Best Life You Can With This Pain?" A Qualitative Study of Adults Living With CF and Pain in the Modulator ERA

BACKGROUND

Despite pain's high prevalence and impact on quality of life and health outcomes, no studies have examined psychosocial approaches for treating pain in CF. We interviewed adults with CF and pain about their experiences to inform development of a CF-specific psychosocial pain management intervention.

METHODS

We partnered with CF Community Voice to recruit 14 adults with CF and pain for 1.5 h individual qualitative interviews and conducted a hybrid inductive-deductive thematic analysis (NVivo 14).

RESULTS

Participants' age ranged from 23 to 64 years; Seven were taking a modulator, 4 eligible/not taking, 3 ineligible. Pain sources included lung/chest, head/sinus, joint, bone, back, neuropathic, GI; 100% reported multiple sources. Pain experience: A major theme was the close interrelationship of pain and CF. Subthemes included pain being part of life with CF, having CF leads to high pain tolerance and effects of aging with CF. Participants described CFTR modulators effect pain experiences with 3 noting improvement and 4 worsening pain. Pain centralization was common: fatigue, difficulties with cognition/sleep, increased sensitivity to nonpainful stimuli. Pain impact: Pain has a widespread negative impact on quality of life and especially mental health. Resiliency was a theme: the need for coping strategies, support and strong self-advocacy. Advice for CF Care Teams: Participants endorsed a need for increased acknowledgment of pain experiences and co-development of a treatment plan.

CONCLUSIONS

Pain remains a prominent, burdensome symptom in the modulator era, necessitating a multi-component management approach. Results informed the development and pilot of a mind-body pain intervention for adults with CF.

Pain Self-Management Behaviors in Breast Cancer Survivors Six Months Post-Primary Treatment: A Mixed-Methods, Descriptive Study

Background/Objectives: One-third of breast cancer (BC) survivors experience chronic treatment-related pain (CTP) that requires multimodal management strategies, which may include pain self-management behaviors (PSMBs). Most studies exploring PSMBs focus on patients with advanced cancer, who may differ from survivors in their pain management needs and access to resources. This mixed-methods study explored PSMBs of survivors of BC, referral sources, and goals for pain relief, and examined the relationship between PSMB engagement and pain intensity/interference. Methods: Survivors of BC who were six months post-treatment completed measures assessing their pain intensity/interference and PSMB engagement. Purposive sampling identified a subset of participants who completed interviews, which were analyzed using thematic analysis. Results: Participants (n = 60) were 60 ± 10 years old. Worst Pain Intensity and Pain Interference were 3.93 ± 2.36 and 2.09 ± 2.11, respectively. Participants engaged in 7 ± 3.5 PSMBs. The most common were walking (76%) and distraction (76%). PSMBs described in the interviews (n = 10) were arm stretching and strengthening exercises, seeking specialized pain management services, and avoidance. Most PSMBs were self-directed or suggested by friends. All pain relief goals were to minimize pain interference. PSMB engagement was not associated with Worst, Least, or Average Pain Intensity (all rs ≤ -0.2, p ≥ 0.05) but was associated with Pain Interference (rs = 0.3, p ≤ 0.01). Conclusions: The survivors of BC engaged in many PSMBs, with varying levels of effectiveness and a varying quality of supporting evidence. Most PSMBs were self-directed and some required intervention from healthcare providers or other people, while others required access to limited specialized pain management services.

Applying Nociplastic Pain Criteria in Chronic Musculoskeletal Conditions: A Vignette Study

Background/Objectives: The International Association for the Study of Pain (IASP) recently introduced clinical criteria and a grading system to identify nociplastic pain, marking a pivotal step toward improving diagnostic accuracy. This study aimed to evaluate the reliability and validity of the IASP criteria using clinical vignettes, assessing their effectiveness in identifying nociplastic pain in clinical settings. Methods: A reliability and diagnostic accuracy study was conducted using 32 clinical vignettes based on the literature and pre-existing clinical data. The vignettes represented patients with and without the characteristics of nociplastic pain and were reviewed independently by two expert physiotherapists. Inter-rater and intra-rater reliability were evaluated with a 1-month interval between assessments. Criterion validity was analyzed by comparing the IASP criteria against the standardized vignettes as the reference standard. Sensitivity, specificity, and predictive values were calculated to assess diagnostic accuracy. Results: The IASP criteria demonstrated moderate-to-perfect intra-rater agreement (κ = 0.71-1.00, p < 0.05) and weak-to-perfect inter-rater agreement (κ = 0.52-1.00, p < 0.05). Criterion validity was moderate (κ = 0.68), with strong specificity (89.0%) and moderate sensitivity (69.0%). Positive and negative predictive values were high at 81.8% and 81.0%, respectively, supporting the criteria's accuracy in identifying and excluding nociplastic pain. Conclusions: The IASP criteria for nociplastic pain exhibited satisfactory reliability and criterion validity in this preliminary study, particularly after initial rater familiarization. Future research should evaluate their application in real-world clinical settings, explore concurrent and prognostic validity, and involve a broader range of raters to enhance generalizability.

Pain hypersensitivity, sensorimotor impairment, and decreased muscle force in a novel rat model of radiation-induced peripheral neuropathy

INTRODUCTION

Radiation-induced peripheral neuropathy is a rare, but serious complication often resulting in profound morbidity, life-long disability, and chronic debilitating pain. Unfortunately, this type of peripheral neuropathy is usually progressive, and almost always irreversible. To date, a standardized rat model of radiation-induced peripheral neuropathy has not been established. The purpose of the present study was to examine neuropathic pain, sensorimotor impairment, and muscle force parameters following the administration of a clinically relevant radiation dose in a rat model.

METHODS

Ten rats were randomly assigned to one of two experimental groups: (1) radiation and (2) sham-radiated controls. Radiated animals were given a clinically relevant dose of 35 Gray (Gy) divided into five daily doses of 7 Gy/day. This regimen represents a human equivalent dose of 70 Gy, approximating the same dosage utilized for radiotherapy in oncologic patients. Sham-radiated controls were anesthetized and placed in the radiation apparatus but were not given radiation. All animals were tested for baseline values in both sensorimotor and pain behavioral tests. Sensorimotor testing consisted of the evaluation of walking tracks with the calculation of the Sciatic Functional Index (SFI). Pain-related behavioral measures consisted of mechanical allodynia (von Frey test), cold allodynia (Acetone test), and thermal allodynia (Hargreaves test). Animals were tested serially over an 8-week period. At the study endpoint, electrophysiological and muscle force assessments were completed, and histomorphometric analysis was performed on all sciatic nerves.

RESULTS

Animals that underwent radiation treatment displayed significantly greater pain hypersensitivity to mechanical stimulation as compared to sham radiated controls from weeks 4 to 8 of testing. SFI values indicated sensorimotor impairments in the overground gait of radiated animals as compared to non-radiated animals. Furthermore, radiated animals displayed reduced twitch and tetanic muscle force when compared to sham radiated controls.

CONCLUSIONS

A clinically relevant human equivalent dose of fractionated 35 Gy in rats established significant pain hypersensitivity, impairments in sensorimotor locomotion, and decreased muscle force capacity. This novel rodent model of radiation-induced peripheral neuropathy can be utilized to assess the potential efficacy of therapeutic treatments to either prevent or remediate this clinically debilitating condition.

Evaluating pain management practices for cancer patients among health professionals in cancer and supportive/palliative care units: a Belgian survey

BACKGROUND

Pain is reported in 66% of cancer patients with advanced disease. Adequate pain management is a cornerstone of comprehensive supportive cancer care.

PURPOSE

The purpose of this study was to assess pain management in Oncology Units in Belgium.

METHODS

A descriptive research design was applied. A structured questionnaire developed by a writing committee was sent to 37 healthcare professionals in 2021. Twenty-four replied.

RESULTS

In most centers, pain management is organized through the pain clinic (91.7%), followed by a multidisciplinary team (83.3%) and the palliative care unit (75%). Eighty-seven percent use tools to assess the pain, mostly for in-patients. Pain guidelines are applied in 17 centers with the ESMO guidelines being the most often mentioned. Mild to moderate pain is managed with paracetamol, non-steroidal anti-inflammatory drugs, and tramadol. All centers handle severe pain with strong opioids, including buprenorphine and fentanyl. Only 62% are concerned about the side effects of strong opioids. In case of neuropathic pain, treatments with pregabalin, gabapentine, and tricyclic antidepressants are the most common, followed by opioids and interventional therapies for refractory neuropathic pain. Asking advice to the pain clinic, combination therapy and opioid rotation are used for patients with inadequate analgesia. Eighty to 90% of the centers have access to intraspinal and epidural techniques, respectively. An active teaching program on pain relief is offered in 66%, but only 33% of the centers do active research focused on pain management.

CONCLUSIONS

This is the first survey on pain management in the Belgian centers. Surprisingly only one-third of the health professionals ask advice to the pain clinic in case of inadequate pain relief, meaning that we are far away from a multidisciplinary patient-centered approach. Therefore, the BSMO Supportive Care Task Force promotes the development of an interdisciplinary committee in every oncology unit.

Painful Realities: Navigating the Complexities of Head and Neck Cancer Pain

BACKGROUND

Head and neck cancer (HNC) and its treatments can cause significant pain, which can profoundly impact patients' quality of life and treatment outcomes. Understanding the full scope of HNC pain is essential for effective management and improved patient care.

OBJECTIVE

This review aims to comprehensively analyze the multifaceted nature of pain experienced by individuals with HNC, including its various etiologies and management strategies.

RESULTS

HNC pain can arise from tumor extent, treatment-related toxicity, or comorbid conditions. The pathophysiology involves complex interactions between nociceptive, neuropathic, and inflammatory mechanisms. Optimal pain control requires a multimodal patient-tailored approach utilizing both pharmacological and non-pharmacological therapies.

CONCLUSION

Enhancing our understanding of HNC pain and optimizing its management is imperative for improving the overall well-being and treatment outcomes of affected individuals. Future research should focus on understanding detailed pain mechanisms, with the goal of developing personalized pain management strategies and exploring novel therapeutic targets. By implementing comprehensive approaches to HNC pain management, healthcare providers can better support patients through their cancer treatment journey.

Application of the IASP Grading System to Identify Underlying Pain Mechanisms in Patients With Knee Osteoarthritis: A Prospective Cohort Study

OBJECTIVES

This study aimed to apply the International Association for the Study of Pain (IASP) grading system for identifying nociplastic pain in knee osteoarthritis (KOA) awaiting total knee arthroplasty (TKA) and propose criteria to fine-tune decision-making. In addition, the study aimed to characterize a "probable" versus "no or possible" nociplastic pain mechanism using biopsychosocial variables and compare both groups in their 1-year post-TKA response.

METHODS

A secondary analysis of baseline data of a longitudinal prospective study involving 197 patients with KOA awaiting total TKA in Belgium and the Netherlands was performed. Two approaches, one considering 4 and the other 3 pain locations (step 2 of the grading system), were presented. Linear mixed model analyses were performed to compare the probable and no or possible nociplastic pain mechanism groups for several preoperative biopsychosocial-related variables and 1-year postoperative pain. Also, a sensitivity analysis, comparing 3 pain mechanism groups, was performed.

RESULTS

Thirty (15.22%-approach 4 pain locations) and 46 (23.35%-approach 3 pain locations) participants were categorized under probable nociplastic pain. Irrespective of the pain location approach or sensitivity analysis, the probable nociplastic pain group included more woman, was younger, exhibited worse results on various preoperative pain-related and psychological variables, and had more pain 1-year post-TKA compared with the other group.

DISCUSSION

This study proposed additional criteria to fine-tune the grading system for nociplastic pain (except for discrete/regional/multifocal/widespread pain) and characterized a subgroup of patients with KOA with probable nociplastic pain. Future research is warranted for further validation.

Neuropathic Pain in Cancer: What Are the Current Guidelines?

OPINION STATEMENT

Neuropathic cancer pain is experienced by 30-40% of patients with cancer. It significantly reduces quality of life and overall wellbeing for patients living with and beyond cancer. The underlying mechanisms of neuropathic pain in patients with cancer are complex and involve direct tumour involvement, nerve compression or infiltration, chemotherapy and/or radiotherapy-induced nerve damage, or post-surgical complications. It is crucial for healthcare professionals to assess and manage neuropathic cancer pain effectively. There is increasing recognition that standardisation of neuropathic pain assessment leads to tailored management and improved patient outcomes. Pain management strategies, including medication, interventional analgesia, physical and complementary therapy, can help alleviate neuropathic pain and improve the patient's comfort and quality of life.

The Impact of Pain Education Interventions for Cancer Survivors and Caregivers: A Systematic Review with Meta-Analysis

INTRODUCTION

Cancer-related pain is a global health-related problem associated with functional impairment, anxiety, depression, and reduced quality of life. The use of educational interventions for patients and their caregivers has been proposed as a promising tool for overcoming pain in cancer. The aim of this study was to summarize by means of a standardized methodological systematic revision the actual pain education intervention used in cancer patients and their caregivers and to analyze its effects on pain.

METHODS

A search was conducted through PubMed, Web of Science, Scopus and Cinhal from their inception to September 2022. Randomized controlled trials which included pain education interventions were identified. Two reviewers performed independent data extraction and methodologic quality assessments of these studies.

RESULTS

A total of seven studies was included in the study. The meta-analysis showed that pain education interventions have a significant effect on the worst pain; however, there was no effect on average pain.

CONCLUSIONS

Pain education interventions addressed to patients and their caregivers could have positive effects on cancer-related pain. It is recommended that a minimum of three sessions of about one hour's duration be held once a week. Further research needs to be carried out and analyzed on the effects over the long term. Pain education interventions show positive results in improving pain in cancer patients regardless of etiology or extent of the cancer. Studies with better methodological quality should be carried out to address specific components related to education interventions.

Pathology of pain and its implications for therapeutic interventions

Pain is estimated to affect more than 20% of the global population, imposing incalculable health and economic burdens. Effective pain management is crucial for individuals suffering from pain. However, the current methods for pain assessment and treatment fall short of clinical needs. Benefiting from advances in neuroscience and biotechnology, the neuronal circuits and molecular mechanisms critically involved in pain modulation have been elucidated. These research achievements have incited progress in identifying new diagnostic and therapeutic targets. In this review, we first introduce fundamental knowledge about pain, setting the stage for the subsequent contents. The review next delves into the molecular mechanisms underlying pain disorders, including gene mutation, epigenetic modification, posttranslational modification, inflammasome, signaling pathways and microbiota. To better present a comprehensive view of pain research, two prominent issues, sexual dimorphism and pain comorbidities, are discussed in detail based on current findings. The status quo of pain evaluation and manipulation is summarized. A series of improved and innovative pain management strategies, such as gene therapy, monoclonal antibody, brain-computer interface and microbial intervention, are making strides towards clinical application. We highlight existing limitations and future directions for enhancing the quality of preclinical and clinical research. Efforts to decipher the complexities of pain pathology will be instrumental in translating scientific discoveries into clinical practice, thereby improving pain management from bench to bedside.

Uncovering brain functional connectivity disruption patterns of lung cancer-related pain

Pain is a pervasive symptom in lung cancer patients during the onset of the disease. This study aims to investigate the connectivity disruption patterns of the whole-brain functional network in lung cancer patients with cancer pain (CP+). We constructed individual whole-brain, region of interest (ROI)-level functional connectivity (FC) networks for 50 CP+ patients, 34 lung cancer patients without pain-related complaints (CP-), and 31 matched healthy controls (HC). Then, a ROI-based FC analysis was used to determine the disruptions of FC among the three groups. The relationships between aberrant FCs and clinical parameters were also characterized. The ROI-based FC analysis demonstrated that hypo-connectivity was present both in CP+ and CP- patients compared to HC, which were particularly clustered in the somatomotor and ventral attention, frontoparietal control, and default mode modules. Notably, compared to CP- patients, CP+ patients had hyper-connectivity in several brain regions mainly distributed in the somatomotor and visual modules, suggesting these abnormal FC patterns may be significant for cancer pain. Moreover, CP+ patients also showed increased intramodular and intermodular connectivity strength of the functional network, which could be replicated in cancer stage IV and lung adenocarcinoma. Finally, abnormal FCs within the prefrontal cortex and somatomotor cortex were positively correlated with pain intensity and pain duration, respectively. These findings suggested that lung cancer patients with cancer pain had disrupted connectivity in the intrinsic brain functional network, which may be the underlying neuroimaging mechanisms.

Phenotyping of chronic pain in breast cancer survivors: an original study using the cancer pain phenotyping (CANPPHE) Network multidisciplinary international guidelines

PURPOSE

The primary aim of this cross-sectional study is to examine the prevalence of pain phenotypes in breast cancer survivors (BCS). A secondary aim entails examining whether health related quality of life differs between the main pain phenotypes in BCS.

METHODS

BCS who experienced chronic pain were asked to complete the numeric pain rating scale for pain, Margolis pain diagram, and short form 36 (SF-36). Following administration of questionnaires and quantitative sensory examinations were applied. To determine the prevalence of the predominant type of pain, a recently proposed classification system by the Cancer Pain Phenotyping (CANPPHE) Network was used.

RESULTS

Of the 86 female participants, 19 (22.09%) had dominant neuropathic pain, 18 (20.93%) had dominant nociceptive pain and 14 (16.28%) had dominant nociplastic pain. 35 participants (40.70%) were classified as having mixed pain. One-way ANOVA revealed a significant difference between the four pain groups for the SF-36 general health (F = 3.205, p = 0.027), social functioning (F = 4.093, p = 0.009), and pain (F = 3.603, p = 0.017) subscale scores.

CONCLUSION

This study found that pain in BCS was mostly of mixed phenotype, followed by predominantly neuropathic and nociplastic pain. Furthermore, it was found that, compared to BCS with predominant neuropathic and nociceptive pain, BCS with predominant nociplastic pain have lower health related quality of life in the areas of bodily pain and social functioning.

The Classification of Suspected Predominant Nociplastic Pain in People with Moderate and Severe Haemophilia: A Secondary Exploratory Study

In people with haemophilia (PwH), joint pain is a major comorbidity that is often overlooked and under-treated. It is believed that, to ensure the most successful outcome, pain management should be tailored to the predominant pain phenotype (i.e., nociceptive, neuropathic and nociplastic). The 2021 clinical criteria and grading system for nociplastic pain, established by the International Association for the Study of Pain (IASP), emphasize the necessity of early-stage identification and predominant pain type classification. Consistent with findings in other chronic musculoskeletal pain conditions, studies suggest that a subgroup of PwH suffers from nociplastic pain, i.e., pain arising from altered nociception rather than structural damage, but this has not yet been explored in PwH. This study aimed to identify PwH with "unlikely", "possible" and "probable" nociplastic pain and investigate differences in anthropometric, demographic and clinical characteristics and psychological factors between subgroups of PwH and healthy individuals.: The IASP clinical criteria and grading system were used to classify pain types in adult men with moderate or severe haemophilia recruited from two Belgian haemophilia treatment centres. Statistical analyses were applied to study between-subgroup differences. Of 94 PwH, 80 PwH (85%) were classified with "unlikely" and 14 (15%) with "at least possible" nociplastic pain (including 5 PwH (5%) with "possible" and 9 PwH (10%) with "probable" nociplastic pain). PwH in both the "unlikely" and "at least possible" nociplastic pain groups showed significantly higher levels of unhelpful psychological factors compared to healthy individuals. Additionally, age may partially account for the observed differences in body height and psychological factors. Larger sample sizes may be needed to detect more subtle between-group differences. study confirmed the presence of nociplastic pain in haemophilia, categorising a notable subgroup as individuals who experience at least possible nociplastic pain. These exploratory insights may provide a starting point for future studies and the development of more effective and tailored pain management.

Central Sensitization in Cancer Survivors and Its Clinical Implications: State of the Art

Although the prevalence of cancer pain is 47% after treatment, cancer pain is often underestimated, and many patients are undertreated. The complexity of cancer pain contributes to the lack of its management. Recently, as the mechanism of cancer pain, it has become clear that central sensitization (CS) influences chronic pain conditions and the transition from acute to chronic pain. In this state-of-the-art review, we summarized the association of CS or central sensitivity syndrome with pain and the treatment for pain targeting CS in cancer survivors. The management of patients with CS should not only focus on tissue damage in either the affected body regions or within the central nervous system; rather, it should aim to target the underlying factors that sustain the CS process. Pain neuroscience education (PNE) is gaining popularity for managing chronic musculoskeletal pain and could be effective for pain and CS in breast cancer survivors. However, there is a study that did not demonstrate significant improvements after PNE, so further research is needed. Precision medicine involves the classification of patients into subgroups based on a multifaceted evaluation of disease and the implementation of treatment tailored to the characteristics of each patient, which may play a central role in the treatment of CS.

What Do We Know about Nociplastic Pain?

Nociplastic pain is a recently distinguished type of pain, distinct from neuropathic and nociceptive pain, and is well described in the literature. It is often mistaken for central sensitization. Pathophysiology has not been clearly established with regard to alteration of the concentration of spinal fluid elements, the structure of the white and gray matter of the brain, and psychological aspects. Many different diagnostic tools, i.e., the painDETECT and Douleur Neuropathique 4 questionnaires, have been developed to diagnose neuropathic pain, but they can also be applied for nociplastic pain; however, more standardized instruments are still needed in order to assess its occurrence and clinical presentation. Numerous studies have shown that nociplastic pain is present in many different diseases such as fibromyalgia, complex regional pain syndrome type 1, and irritable bowel syndrome. Current pharmacological and nonpharmacological treatments for nociceptive and neuropathic pain are not entirely suitable for treating nociplastic pain. There is an ongoing effort to establish the most efficient way to manage it. The significance of this field has led to several clinical trials being carried out in a short time. The aim of this narrative review was to discuss the currently available evidence on pathophysiology, associated diseases, treatment possibilities, and clinical trials. It is important that physicians widely discuss and acknowledge this relatively new concept in order to provide optimized pain control for patients.

Diagnosing nociplastic pain in cancer survivors: a major step forward

Nociplastic pain syndromes include particular fibromyalgia, irritable bowel syndrome, headache, complex regional pain syndrome, and idiopathic orofacial pain. Several mechanisms have been proposed to account for nociplastic pain including central sensitisation, alterations of pain modulatory controls, epigenetic changes, and peripheral mechanisms. Importantly, nociplastic pain might also be present in patients with cancer pain, particularly those with pain related to complications of cancer treatment. Increased awareness of nociplastic pain associated with cancer should have important implications for monitoring and managing such patients.

Effects of Physical Exercise and Motor Activity on Oxidative Stress and Inflammation in Post-Mastectomy Pain Syndrome

It is estimated that 10–50% of interventions can generate persistent post-surgical pain. Chronic post-mastectomy pain is a condition persisting for at least three months after surgery. It has been shown that physical activity in the cancer patient allows the improvement of the pain symptom. The aim of this study was to evaluate the effects of physical activity on the intensity and interference of chronic pain in the quality of life of women underwent mastectomy needed for breast cancer removal. The secondary objective was to measure the effects of physical activity on inflammatory and oxidative markers in the same population. A Numeric Rating Scale (NRS) was used to assess pain intensity, and Brief Inventory Pain (BIP) was used for assessing interference of pain in quality of life. Physical activity was measured with the International Physical Activity Questionnaire (IPAQ). Inflammatory mediators such as interleukin (IL)-6, IL-8, tumor necrosis factor (TNF)-α, c-reactive protein (CRP), and biomarkers of oxidative stress malondialdehyde (MDA), superoxide dismutase (SOD), and catalase (CAT) were evaluated in the blood of patients. All the evaluations were performed after three and six months after surgery. Results showed that adequate physical activity can diminish intensity and interference of pain and that these effects are associated with a reduction of blood biomarkers of inflammation.