Pain Management in Childhood Leukemia: Diagnosis and Available Analgesic Treatments

The Pharmacological Treatment of Neuropathic Pain in Children

The International Association for the Study of Pain (IASP) defines neuropathic pain as pain caused by a lesion or disease of the somatosensory nervous system. It is characterized as a clinical condition in which diagnostic studies reveal an underlying cause of an abnormality in the peripheral or central nervous system. Many common causes of neuropathic pain in adults are rare in children. The purpose of this focused narrative review is, to 1) provide an overview of neuropathic pain in children, 2) highlight unique considerations related to the diagnosis and mechanisms of neuropathic pain in children, and 3) perform a comprehensive analysis of the pharmacological treatments available. We emphasize that data for routine use of pharmacological agents in children with neuropathic pain are largely inferred from adult literature with little research performed on pediatric populations, yet have clear evidence of harms to pediatric patients. Based on these findings, we propose risk mitigation strategies such as utilizing topical treatments whenever possible, assessing pain phenotyping to guide drug class choice, and considering pharmaceuticals in the broader context of the multidisciplinary treatment of pediatric pain. Furthermore, we highlight important directions for future research on pediatric neuropathic pain treatment.

The Genetic Causal Association between Educational Attainment and Risk of 12 Common Musculoskeletal Disorders: A Two-Sample Mendelian Randomization

OBJECTIVE

In numerous observational studies, there has been an indication that educational attainment (EA) can impact the intensity of pain and disability resulting from chronic musculoskeletal disorders. Nonetheless, the association observed in these studies is not entirely conclusive. The aim of this study was to investigate the genetic causal relationship between educational attainment and 12 musculoskeletal disorders using Mendelian randomization (MR).

METHODS

The meta-analysis of genome-wide association studies (GWAS) identified 3952 single-nucleotide polymorphisms (SNPs) associated with educational attainment (EA) from the Social Science Genetic Association Consortium (SSGAC). Genetic data for 12 musculoskeletal disorders, including osteonecrosis, osteoporosis, osteomyelitis, low back pain, gout, spinal stenosis, rheumatoid arthritis, meniscus derangement, rotator cuff syndrome, ankylosing spondylitis, cervicobrachial syndrome, and lateral epicondylitis, were obtained from the FinnGen consortium. We conducted a two-sample Mendelian randomization analysis to examine the causal effect of EA on the risk of these musculoskeletal disorders using the TwoSampleMR package in R.

RESULTS

Based on the inverse-variance weighted (IVW) method, we found that a genetically predicted per standard deviation (SD) increase in EA was inversely associated with low back pain [odds ratio (OR) 0.46, 95% confidence interval (Cl) 0.51-0.61, p < 0.001], spinal stenosis (OR 0.62, 95% Cl 0.54-0.71, p < 0.001), rheumatoid arthritis (OR 0.65, 95% Cl 0.55-0.76, p < 0.001), meniscus derangement (OR 0.73, 95% Cl 0.65-0.82, p < 0.001), rotator cuff syndrome (OR 0.55, 95% Cl 0.49-0.61, p < 0.001), cervicobrachial syndrome (OR 0.50, 95% Cl 0.42-0.60, p < 0.001), and lateral epicondylitis (OR 0.30, 95% Cl 0.24-0.37, p < 0.001). There was no causal association between EA and osteonecrosis (OR 1.11, 95% CI 0.76-1.72, p = 0.60), osteoporosis (OR 0.91, 95% CI 0.65-1.27, p = 0.59), or osteomyelitis (OR 0.90, 95% CI 0.75-1.01, p = 0.22). Genetic predisposition to EA had a suggestive causal association with gout (OR 0.80, 95% CI 0.68-0.95, p = 0.01) and ankylosing spondylitis (OR 0.64, 95% CI 0.45-0.91, p = 0.01) after Bonferroni correction. None of the analyses revealed any horizontal pleiotropy or heterogeneity.

CONCLUSION

In our investigation, we have uncovered evidence supporting a causal relationship between low level of EA and the incidence of certain musculoskeletal disorders. In the future, it is imperative to ascertain risk factors such as lifestyle patterns linked with EA to uncover the underlying causal relationship and offer informed interventions for individuals.

Evaluation of vincristine-induced peripheral neuropathy in children with cancer: Turkish validity and reliability study

BACKGROUND

The evaluation of peripheral neuropathy in children receiving Vincristine treatment is challenging. This study examined the Turkish validity and reliability of the Total Neuropathy Score-Pediatric Vincristine (TNS-PV) measurement tool, which can measure Vincristine-induced peripheral neuropathy symptoms in children with cancer.

METHODS

A total of 53 children aged 5-17 years who received Vincristine treatment in two pediatric hematology-oncology centers participated in the study. Data was collected using the Total Neuropathy Score-Pediatric Vincristine (TNS-PV), the Common Terminology Criteria for Adverse Events (CTCAE), the Wong-Baker FACES Pain Scale, and the Adolescent Pediatric Pain Tool (APPT). The correlation between the TNS-PV total score and other scales and the inter-rater reliability coefficient was evaluated.

FINDINGS

Of the children, 81.1% were diagnosed with ALL and 13.2% with Ewing Sarcoma. Cronbach's alpha values of form A and B of the TNS-PV scale were 0.628 and 0.639, respectively. As the cumulative Vincristine dose increased, the children's scores on TNS-PV were higher. A moderate and significant positive correlation was found between the TNS-PV form A total score and the worst subjective symptoms a, b (A), strength, tendon reflexes, and autonomic / constipation (r = 0.441, r = 0.545, r = 0.472, r = 0.536, p < 0.01).

DISCUSSION

The TNS-PV form B total score was found to have a moderate level, significant correlation with CTCAE sensory neuropathy score and Wong-Baker FACES Pain Scale, and a high level, significant positive correlation with CTCAE motor neuropathy score.

APPLICATION TO PRACTICE

The TNS-PV is valid and reliable for measuring Vincristine-induced peripheral neuropathy in practice in Turkish children 5 years and older.

A Retrospective Cohort Study of the Efficacy, Safety, and Clinical Value of 6-TG versus 6-MP Maintenance Therapy in Children with Acute Lymphoblastic Leukemia

Objective

To explore the efficacy, safety, and clinical value of 6-TG versus 6-MP when treating childhood acute lymphoblastic leukemia (ALL).

Methods

The study period was from January 2017 to June 2021. The subjects of this study were 100 children with ALL who were treated in our hospital. According to different intervention methods, the children who received 6-MP maintenance therapy were selected as the control group, with a total of 57 cases. Children with TG maintenance therapy were included in the research group, a total of 43 cases. The ICNS recurrence rate, non-ICNS recurrence rate, first remission mortality rate, secondary malignant tumor, and other indicators were compared.

Results

First of all, we compared the effective rate: complete remission (CR), partial remission, and nonremission in the study group, and the effective rate was 87.5%. In the control group, there were CR, partial remission, and no remission, and the effective rate was 65.5%. The effective rate of the study group was higher, and the difference between groups was statistically significant (P < 0.05). There were 55 cases of failure in the study group, with an incidence of 21.91%. There were 42 cases of total failure events in the control group, the incidence rate was 18.02%, and there exhibited no remarkable difference (P > 0.05). In the study group, 6 cases died in the first remission, with a fatality rate of 2.39%, while there exhibited no death in the control group. The mortality in the first remission period in the study group was lower (P < 0.05). The overall recurrence rate of the study group was 5.57%, while that of the control group was 11.15%. The overall recurrence rate of the study group was lower, and the difference between groups was statistically significant (P < 0.05). The recurrence rate of ICNS was 2.14% in the study group and 2.98% in the control group, and there exhibited no remarkable difference (P > 0.05). The non-ICNS recurrence rate was 3.43% in the study group and 7.17% in the control group. There exhibited no remarkable difference (P > 0.05). The incidence of secondary malignant tumor events was 0.85% in the study group and 1.59% in the control group. There exhibited no remarkable difference (P > 0.05). The incidence of hepatic vein occlusive disease was 7.29% in the study group and 2.39% in the control group. The incidence of hepatic vein occlusive disease in the study group was higher, and the difference between groups was statistically significant (P < 0.05). Finally, we compared the incidence of adverse reactions. In the study group, there were 12 cases of oral mucosal damage, 7 cases of liver function damage, 6 cases of infection, 10 cases of myelosuppression, 9 cases of gastrointestinal reaction, and 4 cases of skin damage; the incidence rate was 23.17%. In the control group, there were 12 cases of oral mucosal damage, 7 cases of liver function damage, 6 cases of infection, 10 cases of myelosuppression, 9 cases of gastrointestinal reaction, and 4 cases of skin damage, with an incidence of 19.12%. There exhibited no remarkable difference in the incidence of adverse reactions (P > 0.05).

Conclusion

6-TG maintenance therapy in children with ALL can enhance the overall effective rate, can reduce the first remission mortality and the total recurrence rate, and will not increase the overall incidence of adverse reactions, but the incidence of reversible or irreversible hepatic veno-occlusive disease is remarkably increased, which has a certain clinical value.

Background

Treatment-related hepatotoxicity and myelosuppression remain formidable challenges for clinicians. Pharmacokinetic studies found that 6-TG has a more direct intracellular activation pathway, shorter cytotoxic time, and stronger potency than 6-MP. Therefore, this study investigated the efficacy, safety, and clinical value of 6-TG and 6-MP in the treatment of children with ALL.

Supportive methods for childhood acute lymphoblastic leukemia then and now: A compilation for clinical practice

Survival of childhood acute lymphoblastic leukemia has significantly improved over the past decades. In the early years of chemotherapeutic development, improvement in survival rates could be attained only by increasing the cytostatic dose, also by modulation of the frequency and combination of chemotherapeutic agents associated with severe short- and long-time side-effects and toxicity in a developing child's organism. Years later, new treatment options have yielded promising results through targeted immune and molecular drugs, especially in relapsed and refractory leukemia, and are continuously added to conventional therapy or even replace first-line treatment. Compared to conventional strategies, these new therapies have different side-effects, requiring special supportive measures. Supportive treatment includes the prevention of serious acute and sometimes life-threatening events as well as managing therapy-related long-term side-effects and preemptive treatment of complications and is thus mandatory for successful oncological therapy. Inadequate supportive therapy is still one of the main causes of treatment failure, mortality, poor quality of life, and unsatisfactory long-term outcome in children with acute lymphoblastic leukemia. But nowadays it is a challenge to find a way through the flood of supportive recommendations and guidelines that are available in the literature. Furthermore, the development of new therapies for childhood leukemia has changed the range of supportive methods and must be observed in addition to conventional recommendations. This review aims to provide a clear and recent compilation of the most important supportive methods in the field of childhood leukemia, based on conventional regimes as well as the most promising new therapeutic approaches to date.

The Role of Genetic Polymorphisms in High-Dose Methotrexate Toxicity and Response in Hematological Malignancies: A Systematic Review and Meta-Analysis

Objective: High-dose methotrexate (HDMTX) is a mainstay therapeutic agent for the treatment of diverse hematological malignancies, and it plays a significant role in interindividual variability regarding the pharmacokinetics and toxicity. The genetic association of HDMTX has been widely investigated, but the conflicting results have complicated the clinical utility. Therefore, this systematic review aims to determine the role of gene variants within the HDMTX pathway and to fill the gap between knowledge and clinical practice. Methods: Databases including EMBASE, PubMed, Cochrane Central Register of Controlled Trials (CENTRAL), and the Clinical Trials.gov were searched from inception to November 2020. We included twelve single-nucleotide polymorphisms (SNPs) within the HDMTX pathway, involving RFC1, SLCO1B1, ABCB1, FPGS, GGH, MTHFR, DHFR, TYMS, and ATIC. Meta-analysis was conducted by using Cochrane Collaboration Review Manager software 5.3. The odds ratios (ORs) or hazard ratios (HRs) with 95% confidence interval (95% CI) were analyzed to evaluate the associations between SNPs and clinical outcomes. This study was performed according to the PRISMA guideline. Results: In total, 34 studies with 4102 subjects were identified for the association analysis. Nine SNPs involving MTHFR, RFC1, ABCB1, SLCO1B1, TYMS, FPGS, and ATIC genes were investigated, while none of studies reported the polymorphisms of GGH and DHFR yet. Two SNPs were statistically associated with the increased risk of HDMTX toxicity: MTHFR 677C>T and hepatotoxicity (dominant, OR=1.52, 95% CI=1.03-2.23; recessive, OR=1.68, 95% CI=1.10-2.55; allelic, OR=1.41, 95% CI=1.01-1.97), mucositis (dominant, OR=2.11, 95% CI=1.31-3.41; allelic, OR=1.91, 95% CI=1.28-2.85), and renal toxicity (recessive, OR=3.54, 95% CI=1.81-6.90; allelic, OR=1.89, 95% CI=1.18-3.02); ABCB1 3435C>T and hepatotoxicity (dominant, OR=3.80, 95% CI=1.68-8.61), whereas a tendency toward the decreased risk of HDMTX toxicity was present in three SNPs: TYMS 2R>3R and mucositis (dominant, OR=0.66, 95% CI=0.47-0.94); RFC1 80A>G and hepatotoxicity (recessive, OR=0.35, 95% CI=0.16-0.76); and MTHFR 1298A>C and renal toxicity (allelic, OR=0.41, 95% CI=0.18-0.97). Since the data of prognosis outcomes was substantially lacking, current studies were underpowered to investigate the genetic association. Conclusions: We conclude that genotyping of MTHFR and/or ABCB1 polymorphisms prior to treatment, MTHFR 677C>T particularly, is likely to be potentially useful with the aim of tailoring HDMTX therapy and thus reducing toxicity in patients with hematological malignancies.

Astaxanthin Relieves Busulfan-Induced Oxidative Apoptosis in Cultured Human Spermatogonial Stem Cells by Activating the Nrf-2/HO-1 pathway

Many child cancer patients endure anticancer therapy containing alkylating agents before sexual maturity. Busulfan (BU), as an alkylating agent, is a chemotherapy drug, causing DNA damage and cytotoxicity in germ cells. In the present study, we aimed to investigate the protective effect of astaxanthin (AST), as a potent antioxidant and powerful reactive oxygen species (ROS) scavenger, on BU-induced toxicity in human spermatogonial stem cells. For this purpose, testes were obtained from four brain-dead donors. After tissue enzymatic digestions, testicular cells were cultured for 3 weeks for spermatogonial stem cell (SSC) isolation and purification. K562 cell line was cultured to survey the effect of AST on cancer treatment. The cultured SSCs and K562 cell line were finally treated with AST (10μM), BU (0.1nM), and AST+BU. The expression of NRF-2, HO-1, SOD2, SOD3, TP53, and apoptotic genes, including CASP9, CASP3, BCL2, and BAX, were assayed using real-time PCR. Moreover, ROS level in different groups and malondialdehyde level and total antioxidant capacity in cell contraction of SSCs were measured using ELISA. Data showed that AST significantly upregulated the expression of NRF-2 gene (P<0.001) and protein (P<0.005) and also significantly decreased the production of BU-induced ROS (P<0.001). AST activated the NRF-2/HO-1 pathway that could remarkably restrain BU-induced apoptosis in SSCs. Interestingly, AST upregulated the expression level of apoptosis genes in the K562 cell line. The results of this study indicated that AST reduces the side effects of BU on SSCs without interference with its chemotherapy effect on cancerous cells through modulation of the NRF-2/HO-1 and mitochondria-mediated apoptosis pathways.

Ankle osteonecrosis in fifty-one children and adolescent's leukemia survivors: a prospective randomized study on percutaneous mesenchymal stem cells treatment

PURPOSE

Corticoid treatment associated with haematologic treatments can lead to ankle osteonecrosis in children's survivors of acute leukemia (ALL). Based on the efficiency of mesenchymal stem cells (MSCs) in hip osteonecrosis, we performed an evaluation of this treatment in 51 children and adolescents who had symptomatic ankle osteonecrosis after therapy for haematologic cancer.

MATERIAL AND METHODS

The 51 patients had a total of 79 osteonecrosis sites on MRI, with 29 talus sites, 18 metaphyseal tibia sites, 12 epiphyseal tibia sites, eight calcaneus sites, six fibula sites, four navicular sites, and two cuboid sites. In this prospective randomized trial, 37 ankles were addressed for cell therapy, 37 others for core decompression alone, and 20 were considered as a control group without treatment. We analyzed the outcome of this treatment osteonecrosis, the number and characteristics of bone marrow mesenchymal cells (MSCs) that could be transplanted, and the risks of tumorigenesis in these patients with haematologic cancers. The patients were operated on over a period of ten years from 2000 to 2010 and were monitored through December 31, 2019.

RESULTS

Despite a normal systemic blood cells count, MSCs in the iliac crest (counted as CFU-F) were in low number (1021 MSCs/mL; range 314-3015) and were of host origin after even allogeneic bone marrow transplantation. Better clinical outcomes (pain, foot and ankle deformity) and osteonecrosis repair on MRI with absence of collapse were obtained in ankles that received cell therapy as compared with those with core decompression alone or those without initial surgery. No tumour was found on MRI at the sites of injection and this study found no increased risk of recurrence or of new cancer in this population after an average follow-up of 15 years.

CONCLUSIONS

These results suggest that autologous MSCs can improve the quality of life of leukemia survivors with ankle osteonecrosis.