Long-term alterations in somatosensory functioning in survivors of childhood cancer

Pain Catastrophizing Moderates the Relationship Between Pain Sensitivity and Clinical Pain in Adolescents With Functional Abdominal Pain

Pain catastrophizing has been linked to amplified pain sensitivity assessed using quantitative sensory testing (QST) in adults; pediatric data are limited, particularly in youth with functional abdominal pain (FAP). With increasing use of QST to evaluate somatosensory function and predict pain outcomes, we examined the associations between QST and clinical pain in adolescents with FAP and tested the moderating effects of pain catastrophizing. Seventy-seven adolescents (mean age 16.6 years, 85.7% female, 72.7% White, 90.8% non-Hispanic) who fulfilled diagnostic criteria for FAP completed QST assessment (pressure pain threshold and tolerance, heat pain threshold, conditioned pain modulation) and measures of abdominal pain intensity, pain interference, and pain catastrophizing. Adjusting for age and sex, only higher heat pain threshold was associated with higher abdominal pain intensity (Beta per 1-standard deviation = .54, P = .026). Contrary to hypothesis, for youth with higher pain catastrophizing, higher pressure pain tolerance was associated with greater abdominal pain intensity, but associations were not significant for youth with lower catastrophizing (P = .049). Similarly, for those with higher pain catastrophizing (in contrast to lower pain catastrophizing), higher pressure pain thresholds and tolerance were associated with higher pain interference (P = .039, .004, respectively). Results highlight the need to investigate the influence of pain catastrophizing on QST. PERSPECTIVE: This study demonstrated unexpected findings of pain catastrophizing moderating the relationships between pressure pain threshold and tolerance, and clinical pain in adolescents with FAP. This raised questions regarding our understanding of psychological contributions to QST findings in pediatric populations with chronic pain.

Sensitivity and Specificity of a Neuropathic Screening Tool (Self-Report Leeds Assessment of Neuropathic Symptoms and Signs, S-LANSS) in Adolescents With Moderate-Severe Chronic Pain

Neuropathic screening tools improve recognition of neuropathic pain in adults. Although utilized in pediatric populations, the sensitivity, specificity and methodology of screening tool delivery have not been compared in children. We evaluated the Self-Report Leeds Assessment of Neuropathic Symptoms and Signs (S-LANSS) in adolescents (10-18 years) referred to a tertiary pediatric pain clinic. History and examination by specialist clinicians and multidisciplinary assessment informed classification of the primary pain type. In a prospective cohort, scores were obtained at interview (S-LANSS interview; n = 161, 70% female), and following substitution of self-reported signs with examination findings in the primary pain region (Leeds Assessment of Neuropathic Symptoms and Signs, LANSS examination). Secondly, we retrospectively retrieved questionnaires self-completed by adolescents at their initial clinic appointment (S-LANSS self-completed; n = 456, 73% female). Thirdly, we explored relationships between patient-reported outcomes and S-LANSS scores. S-LANSS interview scores varied with pain classification, and S-LANSS self-completed scores were similarly highest with neuropathic pain (median [interquartile range]: 18 [11, 21]) and complex regional pain syndrome (21 [14, 24]), variable with musculoskeletal pain (13 [7, 19]) and lowest with visceral pain (6.5 [2, 11.5]) and headache (8.5 [4, 14]). As in adults, the cutpoint score of 12/24 was optimal. Sensitivity was highest with inclusion of examination findings and lowest with self-completion (LANSS examination vs S-LANSS interview vs S-LANSS self-completed: 86.3% vs 80.8% vs 74.7%), but specificity was relatively low (37.8% vs 36.7% vs 48%). High S-LANSS scores in non-neuropathic groups were associated with female sex and high pain catastrophizing. The S-LANSS is a sensitive screening tool for pain with neuropathic features in adolescents, but needs to be interpreted in the context of clinical evaluation (clinicaltrials.gov NCT03312881). PERSPECTIVE: This article reports high sensitivity of the S-LANSS screening tool for identifying pain with neuropathic features in adolescents with moderate-severe chronic pain. However, as sensitivity is lower than in adult populations, further interdisciplinary evaluation is necessary to inform diagnosis and management.

Exploring Serum Biomarkers for Neuropathic Pain in Rat Models of Chemotherapy-Induced Peripheral Neuropathy: A Comparative Pilot Study with Oxaliplatin, Paclitaxel, Bortezomib, and Vincristine

Blood biomarkers, including neurofilament light chain (NfL), have garnered attention as potential indicators for chemotherapy-induced peripheral neuropathy (CIPN), a dose-limiting adverse effect of neurotoxic anticancer drugs. However, no blood biomarker has been established for routine application or translational research. This pilot study aimed to evaluate a limited panel of blood biomarkers in rat models of CIPN and their correlations with neuropathic pain. CIPN models were induced through repeated injections of oxaliplatin, paclitaxel, bortezomib, and vincristine. Electronic von Frey testing was used to assess tactile allodynia. Post anticancer injections, serum concentrations of 31 proteins were measured. Allodynia thresholds decreased in anticancer-treated animals compared to controls. No consistent modifications were observed in the biomarkers across CIPN models. The most noteworthy biomarkers with increased concentrations in at least two CIPN models were NfL (paclitaxel, vincristine), MCP-1, and RANTES (oxaliplatin, vincristine). Vincristine-treated animals exhibited strong correlations between LIX, MCP-1, NfL, and VEGF concentrations and tactile allodynia thresholds. No single biomarker can be recommended as a unique indicator of CIPN-related pain. Because of the study limitations (single dose of each anticancer drug, young animals, and single time measurement of biomarkers), further investigations are necessary to define the kinetics, specificities, and sensitivities of MCP-1, RANTES, and NfL.

Feasibility and reliability of a quantitative sensory testing protocol in youth with acute musculoskeletal pain postsurgery or postinjury

ABSTRACT

Quantitative sensory testing (QST) is increasingly used in pediatric chronic pain; however, assessment in youth with acute musculoskeletal (MSK) pain is limited. This study evaluated the feasibility, reliability, and sources of variability of a brief QST protocol in 2 clinical samples of youth with acute MSK pain. Participants were 277 youth (M age = 14.5 years, SD = 2.0, range = 11-18 years, 59% female, 81% non-Hispanic) across 3 geographic study sites who completed a QST protocol assessing pressure and thermal pain sensitivity, temporal summation of pain, and conditioned pain modulation 8 weeks after MSK surgery (n = 100) or within 4 weeks after an acute MSK injury (n = 177). High feasibility was demonstrated by protocol completion rates ranging from 97.5% to 100% for each task, with 95.3% of youth completing all tasks. Reliability was high, with reliability coefficients of >0.97 for 7 out of 8 QST parameters and minimal influence of examiner or participating site effects. Younger youth had lower pressure and heat pain thresholds (11-12 vs 13-18 years, d = -0.80 to -0.56) and cold pain tolerance (d = -0.33). Hispanic youth had higher pressure and heat pain thresholds (d = 0.37-0.45) and pain ratings for cold pain tolerance (d = 0.54) compared with non-Hispanic youth. No significant differences were observed in QST values by sex or personal contextual factors at the time of assessment (momentary pain, menstrual period, use of pain medications). Overall findings demonstrate feasibility of a brief QST protocol with youth with diverse acute MSK pain and data provide initial support for the reliability of this QST protocol for multisite research studies.

Pain and Fear of Cancer Recurrence in Survivors of Childhood Cancer

OBJECTIVES

Theoretical models suggest that anxiety, pain intensity, and pain catastrophizing are implicated in a cycle that leads to heightened fear of cancer recurrence (FCR). However, these relationships have not been empirically examined. The objective of this study was to examine the relationships between anxiety symptoms, pain intensity, pain catastrophizing, and FCR in childhood cancer survivors and their parents and to examine whether pain catastrophizing predicts increased FCR beyond anxiety symptoms and pain intensity.

METHODS

The participants were 54 survivors of various childhood cancers (Mage=13.1 y, range=8.4 to 17.9 y, 50% female) and their parents (94% mothers). Children reported on their pain intensity in the past 7 days. Children and parents separately completed measures of anxiety symptoms, pain catastrophizing, and FCR.

RESULTS

Higher anxiety symptoms were associated with increased pain intensity, pain catastrophizing, and FCR in childhood cancer survivors. Higher anxiety symptoms and pain catastrophizing, but not child pain intensity, were associated with FCR in parents. Hierarchical linear regression models revealed that pain catastrophizing explained unique variance in both parent (ΔR2=0.11, P<0.01) and child (ΔR2=0.07, P<0.05) FCR over and above the effects of their own anxiety symptoms and child pain.

DISCUSSION

The results of this study provides novel data on the association between pain and FCR and suggests that a catastrophic style of thinking about pain is more closely related to heightened FCR than one's anxiety symptoms or the sensory pain experience in both childhood cancer survivors and their parents. Pain catastrophizing may be a novel intervention target for survivors and parents struggling with fears of recurrence.

Measuring Fear of Cancer Recurrence in Survivors of Childhood Cancer: Development and Preliminary Validation of the FCRI-Child and FCRI-Parent Versions

OBJECTIVE

Fear of cancer recurrence (FCR) is a common and distressing psychosocial concern for adult cancer survivors. Data on this construct in child survivors is limited and there are no validated measures for this population. This study aimed to adapt the Fear of Cancer Recurrence Inventory-Short Form (FCRI-SF) for survivors of childhood cancer aged 8-18 years (FCRI-C) and their parents (FCRI-P) to self-report on their own FCR and to examine the initial psychometric properties.

METHODS

The FCRI-SF was adapted through expert panel input and cognitive interviews with child survivors <18 years. The factor structure, internal consistency and construct and criterion validity of the FCRI-C and FCRI-P were examined in 124 survivors of childhood cancer (43% female; M_age =14.58 years, SD=2.90) and 106 parents (90% mothers).

RESULTS

All FCRI-SF items were retained for the FCRI-C with simplified language. The internal consistencies of the FCRI-C (α= .88) and FCRI-P (α= .83) were good. Exploratory factor analyses yielded one-factor structures for both measures. Higher scores on the FCRI-C and FCRI-P were associated with greater intolerance of uncertainty and pain catastrophizing. Higher child FCR was also related to more hypervigilance to bodily symptoms. Parents with higher FCR reported contacting their child's doctors and nurses and scheduling medical appointments for their child more frequently. Children reported significantly lower FCR compared to parents.

CONCLUSIONS

The FCRI-C and FCRI-P demonstrated strong reliability and preliminary validity. This study offers preliminary data to support the use of the FCRI-C and FCRI-P to measure FCR in survivors of childhood cancer aged 8-18 years and their parents. This article is protected by copyright. All rights reserved.