Comparing osteonecrosis clinical phenotype, timing, and risk factors in children and young adults treated for acute lymphoblastic leukemia

Advances in mechanism and management of bone homeostasis in osteonecrosis: a review article from basic to clinical applications

Osteonecrosis, characterized by bone cell death leading to impaired bone recovery, causes challenges in bone homeostasis maintenance. Bone homeostasis relies on the delicate balance between osteoclasts and osteoblasts, encompassing a series of complex and strictly regulated biological functions. Current treatments, including conservative therapies and surgeries, often fall short of expected outcomes, necessitating a reorientation towards more effective therapeutic strategies according to the pathogenesis. In this review, the authors hierarchically outlined risk factors, emerging mechanisms, and last-decade treatment approaches in osteonecrosis. By connecting mechanisms of bone homeostasis, the authors proposed future research directions should be focused on elucidating risk factors and key molecules, performing high-quality clinical trial, updating practice, and accelerating translational potential.

Symptomatic osteonecrosis in children treated for Hodgkin lymphoma: A population-based study in Sweden, Finland, and Denmark

BACKGROUND

Osteonecrosis (ON) is a potentially disabling skeletal complication of cancer treatment. Although symptomatic osteonecrosis (sON) is well-known in acute lymphoblastic leukemia (ALL), with an incidence around 6%, studies on sON in pediatric Hodgkin lymphoma (HL) are scarce. The aim of this study was to examine the incidence, risk factors, and outcome of sON in children treated for HL.

PROCEDURE

A total of 490 children under 18, diagnosed with HL between 2005 and 2019 in Sweden, Finland, and Denmark were eligible for the study. Data on patient characteristics, HL treatment, and development of sON were collected from patients' medical records. Magnetic resonance imaging scans were used to establish ON diagnosis and grade ON according to the Niinimäki grading system.

RESULTS

Cumulative 2-year incidence of sON among the 489 included patients was 5.5% (n = 30). The risk for developing sON was higher for those with older age (odds ratio [OR] 1.25, 95% confidence interval [CI]: 1.05-1.49, p < .010), female sex (OR 4.45, CI 1.87-10.58, p < .001), high total cumulative glucocorticoid (GC) doses (OR 1.76, 95% CI: 1.21-2.56, p = 0.003), and advanced HL (OR 2.19, 95% CI: 1.03-4.65, p = .042). Four (13.3%) patients underwent major surgical procedures and 13 (43.3%) had persistent symptoms due to ON at follow-up.

CONCLUSIONS

This study shows that sON is as common in pediatric HL as in pediatric ALL, with risk factors such as older age, female sex, high cumulative GC doses, and advanced HL. Future HL protocol development should aim to reduce the burden of ON by modifying GC treatment.

Radiological follow-up of osteonecrosis lesions in children and adolescents with Hodgkin lymphoma

Osteonecrosis (ON) is a common complication of glucocorticoid-based Hodgkin lymphoma (HL) treatment, but the natural evolution and prognosis of ON lesions remain poorly understood. We describe the radiological evolution of ON lesions identified in a Nordic population-based cohort of paediatric HL patients. Magnetic resonance images of suspected ON lesions were centrally reviewed to confirm ON diagnosis and grade the ON lesions according to the Niinimäki classification. The study included 202 ON lesions in 46 patients, of which 77 were joint lesions. Follow-up images were available for 146/202 lesions, with a mean follow-up time of 28 months. During follow-up, 71% of the lesions remained stable, 26% improved or resolved, and 3% progressed. A higher ON grade at diagnosis was associated with a lower likelihood of spontaneous resolution. The likelihood for resolution of ON decreased by 50% for each year of added patient age, when adjusted for sex, ON location, and symptoms. Hip ON showed less spontaneous improvement compared with other joints, and the risk for surgery was 13-fold in hip ON. Grades 3-4 joint ON has the potential to either progress or resolve, warranting follow-up in patients with severe symptoms. Research on secondary prevention should be directed at grade 3-4 joint ON.

Bisphosphonate treatment for skeletal complications in paediatric cancer-Experience from a single tertiary centre

AIMS

The aim was to analyse the use and safety of bisphosphonate treatment for metabolic bone complications in paediatric cancer patients.

METHODS

We retrospectively describe our experience with bisphosphonate treatment in 25 childhood cancer patients (aged <18 years) in a single tertiary hospital between 1999 and 2020.

RESULTS

The most common primary diagnosis was acute lymphoblastic leukaemia (n = 16) and Hodgkin lymphoma (n = 3). Eleven patients (44%) had received allogeneic stem cell transplantation and two patients autologous stem cell transplantation. Sixteen patients (64%) had been treated with radiotherapy, either total-body (n = 11) or local (n = 5). The main indication for bisphosphonates was osteoporosis with vertebral compression fractures in 13/25, osteonecrosis in 6/25 and hypercalcaemia in 2/25. The bisphosphonate treatment was started on average 13 (range 0-76) months after the diagnosis of the bone complication. Bisphosphonate treatment lasted between weeks (hypercalcaemia) to 5 years (severe osteoporosis). Mild, non-symptomatic hypophosphatemia (n = 8), hypocalcaemia (n = 6) and moderate, transient pain (n = 6) were the most common adverse effects. No severe side effects were observed even when bisphosphonates were administered concomitantly with chemotherapy. Bone mineral density significantly improved with the bisphosphonate treatment (mean lumbar spine Z-score -1.17 vs. -0.07, p < 0.001).

CONCLUSION

Bisphosphonate treatment was well tolerated in this paediatric patient cohort.

Chemotherapy-related toxicities follow a typical pattern in children treated for acute lymphoblastic leukaemia

AIM

Acute lymphoblastic leukaemia (ALL) therapy has been associated with a significant burden of toxicities. The aim of this study was to describe the full spectrum of toxic effects associated with childhood ALL.

METHODS

Toxicity-related data were collected from the Nordic Society of Paediatric Haematology and Oncology (NOPHO) ALL-2008 toxicity registry, in which data on 19 clinically relevant toxicities were registered during ALL treatment, and from patient medical records. All patients treated according to the NOPHO ALL-2008 protocol in Oulu University Hospital between 2008 and 2020 were included in the study.

RESULTS

The cohort consisted of 73 patients, 38 of whom were male. Mean age at diagnosis was 6.6 ± 4.2 (range 1.4-16.0) years. All but one of the patients developed at least one treatment-related toxicity and more than half had multiple toxicities. Female sex and older age were associated with a higher tendency towards toxicity. The most common toxicity was vincristine-induced peripheral neuropathy, which was observed in 70 patients. Most toxicities were moderate or severe, but even mild toxicities often affected leukaemia treatment.

CONCLUSION

Moderate and severe treatment-related toxicities are common, and most toxicities occur in a typical pattern in relation to the treatment phases.

Development of osteonecrosis and improved survival in B-ALL: results of Children's Oncology Group Trial AALL0232

Osteonecrosis is a significant toxicity of acute lymphoblastic leukemia (ALL) therapy. In retrospective analyses, superior event-free survival was noted among affected adolescents in an earlier trial. We prospectively assessed osteonecrosis incidence, characteristics, and risk factors in patients 1-30 years with newly diagnosed high-risk B-ALL on COG AALL0232. Patients were randomized to induction dexamethasone vs prednisone, and interim maintenance high-dose methotrexate vs escalating-dose Capizzi methotrexate/pegaspargase. Event-free and overall survival were compared between patients with/without imaging-confirmed osteonecrosis. Osteonecrosis developed in 322/2730 eligible, evaluable patients. The 5-year cumulative incidence was 12.2%. Risk was greater in patients ≥10 years (hazard ratio [HR], 7.23; P < 0.0001), particularly females (HR, 1.37; P = 0.0057), but lower in those with asparaginase allergy (HR, 0.60; P = 0.0077). Among rapid early responders ≥10 years, risk was greater with dexamethasone (HR, 1.84; P = 0.0003) and with prednisone/Capizzi (HR, 1.45; P = 0.044), even though neither therapy was independently associated with improved survival. Patients with osteonecrosis had higher 5-year event-free (HR, 0.51; P < 0.0001) and overall survival (HR, 0.42; P < 0.0001), and this was directly attributable to reduced relapse rates (HR, 0.57; P = 0.0014). Osteonecrosis in high-risk B-ALL patients is associated with improved survival, suggesting an important role for host factors in mediating both toxicity and enhanced efficacy of specific therapies.

PEG-asparaginase treatment regimens for acute lymphoblastic leukaemia in children: a network meta-analysis

BACKGROUND

Asparaginase has played a crucial role in the improvement of survival in children with acute lymphoblastic leukaemia (ALL), which is the commonest cancer among children. Survival rates have steadily increased over decades since the introduction of asparaginase to ALL therapy, and overall survival rates reach 90% with the best contemporary protocols. Currently, polyethylene glycolated native Escherichia coli-derived L-asparaginase (PEG-asparaginase) is the preferred first-line asparaginase preparation. Besides its clinical benefits, PEG-asparaginase is well known for severe toxicities. Agreement on the optimal dose, treatment duration, and frequency of administration has never been reached among clinicians.

OBJECTIVES

Primary objective To assess the effect of the number of PEG-asparaginase doses on survival and relapse in children and adolescents with ALL. Secondary objectives To assess the association between the number of doses of PEG-asparaginase and asparaginase-associated toxicities (e.g. hypersensitivity, thromboembolism, pancreatitis and osteonecrosis). To undertake a network meta-analysis at dose-level in order to generate rankings of the number of doses of PEG-asparaginase used in the treatment for ALL, according to their benefits (survival and relapse) and harms (toxicity).

SEARCH METHODS

We searched CENTRAL, PubMed, Embase, Web of Science databases and three trials registers in November 2021, together with reference checking, citation searching and contact with study authors to identify additional studies.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) comparing different PEG-asparaginase treatment regimens in children and adolescents (< 18 years of age) with first-line ALL treated with multiagent chemotherapy including PEG-asparaginase.

DATA COLLECTION AND ANALYSIS

Using a standardised data collection form, two review authors independently screened and selected studies, extracted data, assessed risk of bias for each outcome using a standardised tool (RoB 2.0) and assessed the certainty of evidence for each outcome using the GRADE approach. Primary outcomes included overall survival, event-free survival and leukaemic relapse. Secondary outcomes included asparaginase-associated toxicities (hypersensitivity, thromboembolism, pancreatitis, sinusoidal obstruction syndrome and osteonecrosis as well as overall asparaginase-associated toxicity). We conducted the review and performed the analyses in accordance with the guidelines of the Cochrane Handbook for Systematic Reviews of Interventions.

MAIN RESULTS

We included three RCTs in the review, and identified an additional four ongoing studies. We judged outcomes of two RCTs to be at low risk of bias in all the Cochrane risk of bias (RoB 2) domains. We rated the remaining study as having some concerns regarding bias. Due to concerns about imprecision, we rated all outcomes as having low- to moderate-certainty evidence.  One study compared intermittent PEG-asparaginase treatment (eight doses of PEG-asparaginase, 1000 IU/m2, intramuscular (IM) administration) versus continuous PEG-asparaginase treatment (15 doses of PEG-asparaginase, 1000 IU/m2, IM) in 625 participants with non-high risk ALL aged 1.0 to 17.9 years. We found that treatment with eight doses probably results in little to no difference in event-free survival compared to treatment with 15 doses (RR 1.01, 95% CI 0.97 to 1.06; moderate-certainty evidence). Compared to treatment with 15 doses, treatment with eight doses may result in either no difference or a slight reduction in hypersensitivity (RR 0.64, 95% CI 0.21 to 1.93; low-certainty evidence), thromboembolism (RR 0.55, 95% CI 0.22 to 1.36; low-certainty evidence) or osteonecrosis (RR 0.68, 95% CI 0.35 to 1.32; low-certainty evidence). Furthermore, we found that treatment with eight doses probably reduces pancreatitis (RR 0.31, 95% CI 0.12 to 0.75; moderate-certainty evidence) and asparaginase-associated toxicity (RR 0.53, 95% CI 0.35 to 0.78; moderate-certainty evidence) compared to treatment with 15 doses. One study compared low-risk standard treatment with additional PEG-asparaginase (six doses, 2500 IU/m2, IM) versus low-risk standard treatment (two doses, 2500 IU/m2, IM) in 1857 participants aged one to nine years old with standard low-risk ALL. We found that, compared to treatment with two doses, treatment with six doses probably results in little to no difference in overall survival (RR 0.99, 95% CI 0.98 to 1.00; moderate-certainty evidence) and event-free survival (RR 1.01, 95% CI 0.99 to 1.04; moderate-certainty evidence), and may result in either no difference or a slight increase in osteonecrosis (RR 1.65, 95% CI 0.91 to 3.00; low-certainty evidence). Furthermore, we found that treatment with six doses probably increases hypersensitivity (RR 12.05, 95% CI 5.27 to 27.58; moderate-certainty evidence), pancreatitis (RR 4.84, 95% CI 2.15 to 10.85; moderate-certainty evidence) and asparaginase-associated toxicity (RR 4.49, 95% CI 3.05 to 6.59; moderate-certainty evidence) compared to treatment with two doses. One trial compared calaspargase (11 doses, 2500 IU/m2, intravenous (IV)) versus PEG-asparaginase (16 doses, 2500 IU/m2, IV) in 239 participants aged one to 21 years with standard- and high-risk ALL and lymphoblastic lymphoma. We found that treatment with 11 doses of calaspargase probably results in little to no difference in event-free survival compared to treatment with 16 doses of PEG-asparaginase (RR 1.06, 95% CI 0.97 to 1.16; moderate-certainty evidence). However, treatment with 11 doses of calaspargase probably reduces leukaemic relapse compared to treatment with 16 doses of PEG-asparaginase (RR 0.32, 95% CI 0.12 to 0.83; moderate-certainty evidence). Furthermore, we found that treatment with 11 doses of calaspargase results in either no difference or a slight reduction in hypersensitivity (RR 1.17, 95% CI 0.64 to 2.13; low-certainty evidence), pancreatitis (RR 0.85, 95% CI 0.47 to 1.52; low-certainty evidence), thromboembolism (RR 0.83, 95% CI 0.48 to 1.42; low-certainty evidence), osteonecrosis (RR 0.63, 95% CI 0.15 to 2.56; low-certainty evidence) and asparaginase-associated toxicity (RR 1.00, 95% CI 0.71 to 1.40; low-certainty evidence) compared to treatment with 16 doses of PEG-asparaginase.

AUTHORS' CONCLUSIONS

We were not able to conduct a network meta-analysis, and could not draw clear conclusions because it was not possible to rank the interventions. Overall, we found that different numbers of doses of PEG-asparaginase probably result in little to no difference in event-free survival across all studies. In two studies, we found that a higher number of PEG-asparaginase doses probably increases pancreatitis and asparaginase-associated toxicities.

Symptomatic osteonecrosis in French survivors of childhood and adolescent leukemia: a clinical and MRI study of LEA cohort

Osteonecrosis (ON) is a known complication of acute leukemia (AL) management, affecting 1%-10% of young patients and resulting in long-term morbidity. Widespread access to MRI over the past decade has allowed earlier detection and more accurate assessment. This study investigated clinical and MRI features of the 129 (2.5%) patients with symptomatic ON retrospectively recruited from the French LEA (Leucémies de l'Enfant et de l'Adolescent, or child and adolescent leukemias) cohort (n = 4,973). We analyzed data concerning ON risk factors, multifocal involvement, severe lesions detected by MRI, and patient quality of life (QoL). ON patients tended to be >10 years old at the time of AL diagnosis (odds ratio [OR]: 22.46; p < 10^-6), female (OR: 1.8; p = 0.002), or treated for relapse (OR: 1.81; p = 0.041). They more frequently suffered from other sequelae (p < 10^-6). Most necroses involved weight-bearing joints, and they were multifocal in 69% of cases. Double-blinded review of MRIs for 39 patients identified severe lesions in 14, usually in the hips. QoL of adolescents and adults was poor and permanently impacted after onset of ON. In conclusion, age >10 at time of AL diagnosis, female sex, and relapse occurrence were risk factors for multifocal ON; MRI revealed severe ON in a third of the patients considered; and ON was associated with persistently poor QoL affecting multiple domains. Future studies should include prospective data addressing ON management and seek to identify genetic markers for targeted screening enabling early ON detection and treatment.

SOHO State of the Art Updates and Next Questions | Asparaginase-Understanding and Overcoming Toxicities in Adults with ALL

The adoption of pediatric-inspired regimens in young adults with newly diagnosed acute lymphoblastic leukemia (ALL) has significantly improved their survival outcomes. Pediatric-inspired regimens in ALL rely profoundly on delivering adequate dosing of non-myelosuppressive drugs of which asparaginase, a bacterial derived agent, is a key component. Asparaginase therapy is associated with a spectrum of unique toxicities that are observed more frequently in adult patients compared to children with ALL, and this observation has contributed to the reluctance of adult oncologists to administer the drug to their patients. Understanding the breadth of asparaginase toxicity and the associated risk factors may help in preventing severe manifestations and allow safer treatment for adults with ALL. In this review, we will discuss the different formulations of asparaginase and the appropriate dosing in adults with ALL. We will further discuss the frequency and risk factors for individual toxicities of asparaginase along with strategies for their prevention and management.

[Osteonecrosis-severe side effect of treatment for acute lymphoblastic leukemia]

Osteonecrosis occurs as an acute and long-term serious side effect in children, adolescents, and adults with acute lymphoblastic leukemia. It is associated with severe pain and reduced mobility, ultimately leading to joint destruction and significant long-term morbidity. The cumulative incidence ranges from 11 to 20% in adolescents and young adults. In symptomatic patients, multiple joints are frequently affected, which in turns poses a risk factor for the development of severe osteonecrosis. The genesis of leukemia-associated osteonecrosis is multifactorial. Risk factors include the use of corticosteroids and asparaginase. These exert their effects on the blood supply to the bone through hypercholesterolemia, hypertriglyceridemia, and hypertension. Bacteriemia, genetic susceptibility, and stem cell transplantation pose additional risk factors. The treatment of osteonecrosis is challenging and not evidence based. Preventive measurements have as yet mainly been tested in preclinical models.

Osteonecrosis in Korean Paediatric and Young Adults with Acute Lymphoblastic Leukaemia or Lymphoblastic Lymphoma: A Nationwide Epidemiological Study

Osteonecrosis (ON) is a serious complication of acute lymphocytic leukaemia (ALL) or lymphoblastic lymphoma (LBL) treatment, and there is little information regarding ON in Korean paediatric and young adult patients. This retrospective cohort study assessed the cumulative incidence of and risk factors for ON using national health insurance claims data from 2008 to 2019 in 4861 ALL/LBL patients. The Kaplan–Meier method was used to estimate the cumulative incidence of ON according to age groups; the Cox proportional hazard regression model was used to identify risk factors related to ON development after diagnosing ALL/LBL. A cause-specific hazard model with time-varying covariates was used to assess the effects of risk factors. Overall, 158 (3.25%) patients were diagnosed with ON, among whom 23 underwent orthopaedic surgeries. Older age, radiotherapy (HR = 2.62, 95% confidence interval (CI) 1.87–3.66), HSCT (HR = 2.40, 95% CI 1.74–3.31), steroid use and anthracycline use (HR = 2.76, CI 1.85–4.14) were related to ON in the univariate analysis. In the multivariate analysis, age and steroid and asparaginase use (HR = 1.99, CI 1.30–3.06) were factors associated with ON. These results suggest that Korean patients with ALL/LBL who used steroids and asparaginase should be closely monitored during follow-up, even among young adult patients.

Orthopaedic adverse events among adolescents and adults treated with asparaginase for acute lymphoblastic leukaemia

Osteonecrosis (ON) is a complication of acute lymphoblastic leukaemia (ALL) treatment with patient- (age, female sex, genetic polymorphisms, presence of metabolic syndrome) and treatment-specific (glucocorticoid type and schedule) risk factors described. The potential role of asparaginase in increasing risk of ON via effects on coagulation, lipid metabolism, and steroid clearance is now also recognised. Paediatric studies consistently identify age as a key risk factor for ON, with adolescents at higher risk than young children. Fewer studies comprehensively report on risk of ON in adults, but available evidence suggests that adolescents and young adults (AYAs) treated with corticosteroid and asparaginase-containing paediatric-inspired regimens are more at risk than older adults treated with paediatric-inspired or traditional adult regimens. There are few proven strategies to prevent or mitigate the severity of ON and other orthopaedic complications of ALL therapy. Future clinical trials should carefully ascertain orthopaedic adverse events in adults. Evidence-based guidelines should be developed for management of orthopaedic adverse events in adults being treated for ALL, especially high-risk AYAs being treated with paediatric-inspired regimens.

Asparaginase Enzyme Activity Levels and Toxicity in Childhood Acute Lymphoblastic Leukemia: a NOPHO ALL2008 study

Overall asparaginase-associated toxicity and relapse were not significantly associated with increased asparaginase enzyme activity levels.

The risk of pancreatitis and osteonecrosis were significantly associated with increasing asparaginase enzyme activity.

Asparaginase treatment is a mainstay in contemporary treatment of acute lymphoblastic leukemia (ALL), but substantial asparaginase-related toxicity may lead to jeopardized protocol compliance and compromises survival. We investigated the association between risk of asparaginase-associated toxicities (AspTox) and asparaginase enzyme activity (AEA) levels in 1155 children aged 1.0 to 17.9 years, diagnosed with ALL between July 2008 and March 2016, and treated according to the Nordic Society of Pediatric Hematology and Oncology (NOPHO) ALL2008 protocol. Patients with ≥2 blood samples for AEA measurement drawn 14 ± 2 days after asparaginase administration were included (6944 trough values). AEA was measurable (or >0 IU/L) in 955 patients, whereas 200 patients (17.3%) had asparaginase inactivation and few AspTox recorded. A time-dependent multiple Cox model of time to any first asparaginase-associated toxicity adjusted for sex and age was used. For patients with measurable AEA, we found a hazard ratio (HR) of 1.17 per 100 IU/L increase in median AEA (95% confidence interval [CI], 0.98-1.41; P = .09). For pancreatitis, thromboembolism, and osteonecrosis, the HRs were 1.40 (95% CI, 1.12-1.75; P = .002), 0.99 (95% CI, 0.70-1.40; P = .96), and 1.36 (95% CI, 1.04-1.77; P = .02) per 100 IU/L increase in median AEA, respectively. No significant decrease in the risk of leukemic relapse was found: HR 0.88 per 100 IU/L increase in AEA (95% CI, 0.66-1.16; P = .35). In conclusion, these results emphasize that overall AspTox and relapse are not associated with AEA levels, yet the risk of pancreatitis and osteonecrosis increases with increasing AEA levels.

SOHO State of the Art Updates and Next Questions: Management of Asparaginase Toxicity in Adolescents and Young Adults with Acute Lymphoblastic Leukemia

A wider use of L-asparaginase in the treatment of children with acute lymphoblastic leukemia has improved cure rates during recent decades and hence led to introduction of pediatric-inspired treatment protocols for adolescents and young adults. In parallel, a range of burdensome, often severe and occasionally life-threatening toxicities have become frequent, including hypersensitivity, hepatotoxicity, hypertriglyceridemia, thromboembolism, pancreatitis, and osteonecrosis. This often leads to truncation of asparaginase therapy, which at least in the pediatric population has been clearly associated with a higher risk of leukemic relapse. Many of the asparaginase induced toxicities are far more common in older patients, but since their relapse rate is still unsatisfactory, the decision to discontinue asparaginase therapy should balance the risk of toxicity with continued asparaginase therapy against the risk of relapse in the individual patient. The underlying mechanisms of most of the asparaginase induced side effects are still unclear. In this review we address the individual toxicities, known risk factors, and their clinical management.

Bisphosphonate treatment in children with acute lymphoblastic leukemia and osteonecrosis - radiological and clinical findings in a national cohort

Background: Osteonecrosis (ON) is a recognized complication of childhood ALL, but its optimal management remains unestablished. This study evaluated the effect of bisphosphonate (BP) treatment on the evolution of ON lesions in childhood ALL.Material and Methods: We included a national cohort of ALL patients diagnosed with symptomatic ON before 18 years of age and treated with BPs (N = 10; five males). Patients were followed both clinically and with serial MRIs. ON lesions were graded according to the Niinimäki classification.Results: The 10 patients had a total of 55 ON lesions. The median age was 13.3 years at ALL diagnosis and 14.8 years at ON diagnosis. Four patients had received HSCT before the ON diagnosis. BPs used were pamidronate (N = 7), alendronate (N = 2) and ibandronate (N = 1). The duration of BP treatment varied between 4 months and 4 years. In 4/10 patients, BP treatment was given during the chemotherapy. BPs were well-tolerated, with no severe complications or changes in kidney function. At the end of follow up 13/55 (24%) ON lesions were completely healed both clinically and radiographically; all these lesions were originally graded 3 or less. In contrast, ON lesions originally classified as grade 5 (joint destruction; N = 4) remained at grade 5. All grade 5 hip joint lesions needed surgical treatment. During BP treatment, the pain was relieved in 7/10 patients. At the end of follow-up, none of the patients reported severe or frequent pain.Conclusion: BP treatment was safe and seemed effective in relieving ON-induced pain in childhood ALL. After articular collapse (grade 5) lesions did not improve with BP treatment. Randomized controlled studies are needed to further elucidate the role of BPs in childhood ALL-associated ON.

A GRIN3A polymorphism may be associated with glucocorticoid-induced symptomatic osteonecrosis in children with acute lymphoblastic leukemia

Aim: To evaluate the association between candidate genetic polymorphisms and glucocorticoid-induced osteonecrosis in Arab children treated for acute lymphoblastic leukemia. Methods: A total of 189 children treated for acute lymphoblastic leukemia were genotyped for four SNPs with allele discrimination assays. The incidence and timing of radiologically confirmed symptomatic grade 4 osteonecrosis were classified based on the Ponte di Legno toxicity working group consensus definition. Results: Thirteen children developed grade 4 osteonecrosis (6.8%), of whom 12 received the intermediate/high-risk treatment protocol. GRIN3A variant allele carriers had to stop dexamethasone therapy earlier resulting in significantly shorter duration of dexamethasone treatment (mean [95% CI]: 75.17 [64.28-86.06] vs 85.90 [81.22-90.58] weeks; p = 0.054) and lower cumulative dose (mean [95% CI]: 1118.11 [954.94-1281.29] vs 1341.14 [1264.17-1418.11] mg/m^2; p = 0.011). Conclusion: This is the first pharmacogenomics evaluation of the association between GRIN3A variants and glucocorticoid-induced osteonecrosis in Arab children.

Bone pain at leukemia diagnosis and other risk factors for symptomatic osteonecrosis in children with acute lymphoblastic leukemia

BACKGROUND

Osteonecrosis is a major cause of acute and long-lasting complications of acute lymphoblastic leukemia (ALL) therapy in children. Our study aimed to evaluate the prevalence, characteristics, risk factors, and outcome of osteonecrosis in children with ALL.

PROCEDURE

The cohort included 559 children aged 1-20 years diagnosed with ALL between 2003 and 2018 at two tertiary medical centers in Israel and enrolled in two consecutive protocols: ALL-IC BFM 2002 and AIEOP-BFM ALL 2009. Symptomatic osteonecrosis was prospectively captured as an adverse event.

RESULTS

Osteonecrosis occurred in 51 patients (9.1%). Ninety-four percent of the events were graded as moderate or severe (grades 3-4, Ponte di Legno Toxicity Working Group classification) and multiple bone involvement was common. Full resolution of osteonecrosis was documented in only 16% of the children (median follow-up 4.2 years). Stepwise logistic regression identified five risk factors for osteonecrosis, with a high predictive value (AUC = 0.88): older ageat ALL diagnosis, high-risk ALL group, T-cell immunophenotype, female gender, and a novel risk factor: bone pain at the time of leukemia diagnosis. In addition, osteonecrosis was less common among children of Arab ethnicity. Thrombophilia and an elevated age-adjusted body mass index were not confirmed as risk factors for osteonecrosis.

CONCLUSION

Due to the low rates of osteonecrosis resolution and its debilitating long-term impact, the identification of patients at high risk for osteonecrosis is important for their inclusion in further studies evaluating potential therapeutic adjustments.

Skeletal adverse events in childhood cancer survivors: An Adult Life after Childhood Cancer in Scandinavia cohort study

The dynamic growth of the skeleton during childhood and adolescence renders it vulnerable to adverse effects of cancer treatment. The lifetime risk and patterns of skeletal morbidity have not been described in a population-based cohort of childhood cancer survivors. A cohort of 26 334 1-year cancer survivors diagnosed before 20 years of age was identified from the national cancer registries of Denmark, Finland, Iceland and Sweden as well as a cohort of 127 531 age- and sex-matched comparison subjects randomly selected from the national population registries in each country. The two cohorts were linked with data from the national hospital registries and the observed numbers of first-time hospital admissions for adverse skeletal outcomes among childhood cancer survivors were compared to the expected numbers derived from the comparison cohort. In total, 1987 childhood cancer survivors had at least one hospital admission with a skeletal adverse event as discharge diagnosis, yielding a rate ratio (RR) of 1.35 (95% confidence interval, 1.29-1.42). Among the survivors, we observed an increased risk for osteonecrosis with a RR of 25.9 (15.0-44.5), osteoporosis, RR 4.53 (3.28-6.27), fractures, RR 1.27 (1.20-1.34), osteochondropathies, RR 1.57 (1.28-1.92) and osteoarthrosis, RR 1.48 (1.28-1.72). The hospitalization risk for any skeletal adverse event was higher among survivors up to the age of 60 years, but the lifetime pattern was different for each type of skeletal adverse event. Understanding the different lifetime patterns and identification of high-risk groups is crucial for developing strategies to optimize skeletal health in childhood cancer survivors.

Severe toxicity free survival: physician-derived definitions of unacceptable long-term toxicities following acute lymphocytic leukaemia

5-year overall survival rates have surpassed 90% for childhood acute lymphocytic leukaemia, but survivors are at risk for permanent health sequelae. Although event-free survival appropriately represents the outcome for cancers with poor overall survival, this metric is inadequate when cure rates are high but challenged by serious, persistent complications. Accordingly, a group of experts in paediatric haematology-oncology, representative of 17 international acute lymphocytic leukaemia study groups, launched an initiative to construct a measure, designated severe toxicity-free survival (STFS), to quantify the occurrence of physician-prioritised toxicities to be integrated with standard cancer outcome reporting. Five generic inclusion criteria (not present before cancer diagnosis, symptomatic, objectifiable, of unacceptable severity, permanent, or requiring unacceptable treatments) were used to assess 855 health conditions, which resulted in inclusion of 21 severe toxicities. Consensus definitions were reached through a modified Delphi process supplemented by two additional plenary meetings. The 21 severe toxicities include severe adverse health conditions that substantially affect activities of daily living and are refractory to therapy (eg, refractory seizures), are without therapeutic options (eg, blindness), or require substantially invasive treatment (eg, cardiac transplantation). Incorporation of STFS assessment into clinical trials has the potential to improve and diversify treatment strategies, focusing not only on traditional outcome events and overall survival but also the frequencies of the most severe toxicities. The two major aims of this Review were to: prioritise and define unacceptable long-term toxicity for patients with childhood acute lymphocytic leukaemia, and define how these toxicities should be combined into a composite quantity to be integrated with other reported outcomes. Although STFS quantifies the clinically unacceptable health tradeoff for cure using childhood acute lymphocytic leukaemia as a model disease, the prioritised severe toxicities are based on generic considerations of relevance to any other cancer diagnosis and age group.

Recent perspectives on the association between osteonecrosis and bone mineral density decline in childhood acute lymphoblastic leukemia

The attention to treatment-related toxicity has increased since the survival of children with acute lymphoblastic leukemia (ALL) has improved significantly over the past few decades. Intensive ALL treatment schedules including corticosteroids and asparaginase have been shown to give rise to skeletal abnormalities such as osteonecrosis and low bone mineral density (BMD), which may lead to debilitating sequelae in survivors. Although osteonecrosis and low BMD are different entities with suggested separate pathophysiological mechanisms, recent studies indicate that osteonecrosis is associated with accelerated BMD decline. Common underlying mechanisms for osteonecrosis and BMD decline are considered, such as an enhanced sensitivity to corticosteroids in children who suffer from both osteonecrosis and low BMD. In addition, restriction of weight-bearing activities, which is generally advised in patients with osteonecrosis, could aggravate BMD decline. This induces a clinical dilemma, since bone stimulation is important to maintain BMD but alternative interventions for osteonecrosis are limited. Furthermore, this recent finding of accelerated BMD decline in children with osteonecrosis emphasizes the need to develop effective preventive measures for osteonecrosis, which may include targeting BMD decline.

Maintenance therapy and risk of osteonecrosis in children and young adults with acute lymphoblastic leukemia: a NOPHO ALL2008 sub-study

PURPOSE

Osteonecrosis is a burdensome treatment-related toxicity that is mostly diagnosed during or soon after 6-mercaptopurine (6MP)/methotrexate (MTX) maintenance therapy for acute lymphoblastic leukemia (ALL), possibly indicating a pathogenic role of these drugs.

METHODS

We prospectively registered symptomatic osteonecrosis during treatment of 1234 patients aged 1.0-45.9 years treated according to the Nordic Society of Hematology and Oncology (NOPHO) ALL2008 protocol. MTX/6MP metabolites were measured as part of the NOPHO ALL2008 maintenance therapy study.

RESULTS

After a median follow-up of 5.6 years [interquartile range (IQR) 3.6-7.5], 68 patients had been diagnosed with symptomatic osteonecrosis. The cumulative incidence was 2.7% [95% confidence interval (CI) 1.6-3.8%] for patients aged < 10 years, 14.9% (95% CI 9.7-20.2%) for patients aged 10.0-17.9 years, and 14.4% (95% CI 8.0-20.8%) for patients aged ≥ 18 years. The median time from diagnosis of ALL to diagnosis of osteonecrosis in these age groups was 1.0 year (IQR 0.7-2.0), 2.0 years (IQR 1.1-2.4), and 2.2 years (IQR 1.8-2.8), respectively (p = 0.001). With 17,854 blood samples available for MTX and 6MP metabolite analysis, neither erythrocyte levels of 6-thioguanine (TG) nucleotides (p > 0.99), methylated 6MP metabolites (p = 0.37), MTX polyglutamates (p = 0.98) nor DNA-TG (p = 0.53) were significantly associated with the hazard of osteonecrosis in Cox models stratified by the three age groups and adjusted for sex.

CONCLUSION

Maintenance therapy intensity determined by 6MP and MTX metabolites was not associated with the risk of developing osteonecrosis in the NOPHO ALL2008 cohort.

Asian population may have a lower incidence of hip osteonecrosis in childhood acute lymphoblastic leukemia

Osteonecrosis (ON), a long-term complication of acute lymphoblastic leukemia (ALL) treatment affects patients' quality of life. Although the incidence of any ON, including asymptomatic, was 21.7% among children with ALL in the U.S., the actual incidence and risk factors in Asia remain unknown. For over 11 years, we performed hip magnetic resonance imaging (MRI) screening to detect asymptomatic ON while initiating maintenance chemotherapy in newly diagnosed children with ALL. Overall, 164 of 175 patients underwent hip MRI screening. The incidence of symptomatic or any ON was 3.0% and 11.6%, respectively. Asymptomatic ON in patients < 10 and ≥ 10 years old was 4.0% and 35.9%, respectively (P < 0.001). In multivariate analysis, age ≥ 10 years was the only significant risk factor. Asymptomatic ON with necrosis of > 30% of the epiphyseal surface of the femoral head was detected in four patients (2.4%). All were ≥ 10 years. Three of them progressed to severe symptomatic ON. The incidence of any ON in Asia may be lower than that seen in the only screening study in the U.S. Future studies should clarify factors affecting such regional differences and develop an effective approach to avoid the progression of ON in children with ALL.

Clinical Utility of Pegaspargase in Children, Adolescents and Young Adult Patients with Acute Lymphoblastic Leukemia: A Review

Acute lymphoblastic leukemia (ALL) is a heterogenous hematological malignancy representing 25% of all cancers in children less than 15 years of age. Significant improvements in survival and cure rates have been made over the past four decades in pediatric ALL treatment. Asparaginases, derived from Escherichia coli and Erwinia chrysanthemi, have become a critical component of ALL therapy since the 1960s. Asparaginases cause depletion of serum asparagine, leading to deprivation of this critical amino acid for protein synthesis, and hence limit survival of lymphoblasts. Pegaspargase, a conjugate of monomethoxypolyethylene glycol (mPEG) and L-asparaginase, has become an integral component of pediatric upfront and relapsed ALL protocols due to its longer half-life and improved immunogenicity profile compared to native asparaginase preparations. Over the past two decades great strides have been made in outcomes for pediatric ALL due to risk stratification, incorporation of multiagent chemotherapy protocols, and central nervous system prophylaxis with pegaspargase having played an important role in this success. However, adolescents and young adults (AYA) with ALL when treated on contemporaneous trials using adult ALL regimens, continue to have poor outcomes. There is increasing realization of adapting pediatric trial regimens for treating AYAs, especially those incorporating higher intensity of chemotherapeutic agents with pegaspargase being one such agent. Dose or treatment-limiting toxicity is observed in 25-30% of patients, most notable being hypersensitivity reactions. Other toxicities include asparaginase-associated pancreatitis, thrombosis, liver dysfunction, osteonecrosis, and dyslipidemia. Discontinuation or subtherapeutic levels of asparaginase are associated with inferior disease-free survival leading to higher risk of relapse, and in cases of relapse, a higher risk for remission failure. This article provides an overview of available evidence for use of pegaspargase in pediatric acute lymphoblastic leukemia.

Bisphosphonate Therapy for Treating Osteonecrosis in Pediatric Leukemia Patients: A Systematic Review

BACKGROUND

Despite improved outcomes in children with leukemia, complications such as osteonecrosis are common. We conducted a systematic review to investigate the role of bisphosphonates in reducing pain, improving mobility, and stabilizing lesions in pediatric leukemia survivors.

METHODS

Using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, we searched the PubMed, Embase, Cochrane, Web of Science, Scopus, CINAHL, and ClinicalTrials.gov databases. Five of 221 articles retrieved met our inclusion criteria.

RESULTS

Bisphosphonates, especially when combined with dietary calcium and vitamin D supplements and physical therapy (supplements/PT) were associated with improved pain and mobility in 54% and 50% of patients, respectively. A significantly greater proportion of patients treated with bisphosphonates (83%) reported mild/moderate pain or no pain compared with those with supplements/PT alone (36%) (P<0.001). Sixty-six percent of patients treated with bisphosphonates achieved improved/full mobility compared with 27% of those treated with supplements/PT alone (P=0.02). However, 46% of patients showed progressive joint destruction despite bisphosphonate therapy. No adverse events were reported, except for acute phase reactions to intravenous therapies.

CONCLUSIONS

Bisphosphonates, when combined with supplements/PT, were associated with less pain and improved mobility, but not prevention of joint destruction in pediatric leukemia patients with osteonecrosis.

Osteonecrosis in Adults With Acute Lymphoblastic Leukemia: An Unmet Clinical Need

Osteonecrosis is a serious complication of antileukemic therapy associated with severe pain and reduced mobility, ultimately leading to joint destruction and significant long-term morbidity. The 5-year cumulative incidence of osteonecrosis ranges from 11% to 20% in adolescents and young adults to 3% to 8% in patients aged 30 years and older. Most symptomatic patients have multiple joints affected, which in turn poses a risk factor for developing severe osteonecrosis. Osteonecrosis has a multifactorial genesis. Treatment-associated risk factors for developing osteonecrosis depend on the therapeutic context including the use of glucocorticosteroids and the simultaneous and/or intensified use of asparaginase (ASP) which may, among others, exert its effect on blood supply to the bone through hypertriglyceridemia, hypercholesterolemia, and hypertension. Allogeneic hematopoietic stem cell transplantation, bloodstream infections, and genetic factors may additionally impact the risk of osteonecrosis. In this article, the authors used the best available evidence in the literature to develop management recommendations for the use in the context of steroid and asparaginase containing regimens. These considerations may be helpful for similar treatment approaches.

Surgical management of symptomatic osteonecrosis and utility of core decompression of the femoral head in young people with acute lymphoblastic leukaemia recruited into UKALL 2003

AIMS

Osteonecrosis (ON) can cause considerable morbidity in young people who undergo treatment for acute lymphoblastic leukaemia (ALL). The aims of this study were to determine the operations undertaken for ON in this population in the UK, along with the timing of these operations and any sequential procedures that are used in different joints. We also explored the outcomes of those patients treated by core decompression (CD), and compared this with conservative management, in both the pre- or post-collapse stages of ON.

METHODS

UK treatment centres were contacted to obtain details regarding surgical interventions and long-term outcomes for patients who were treated for ALL and who developed ON in UKALL 2003 (the national leukaemia study which recruited patients aged 1 to 24 years at diagnosis of ALL between 2003 and 2011). Imaging of patients with ON affecting the femoral head was requested and was used to score all lesions, with subsequent imaging used to determine the final grade. Kaplan-Meier failure time plots were used to compare the use of CD with non surgical management.

RESULTS

Detailed information was received for 85 patients who had developed ON during the course of their ALL treatment. A total of 206 joints were affected by ON. Of all joints affected by ON, 21% required arthroplasty, and 43% of all hips affected went on to be replaced. CD was performed in 30% of hips affected by ON. The majority of the hips were grade 4 or 5 at initial diagnosis of ON. There was no significant difference in time to joint collapse between those joints in which CD was performed, compared with no joint-preserving surgical intervention.

CONCLUSION

There is a high incidence of surgery in young people who have received treatment for ALL and who have developed ON. Our results suggest that CD of the femoral head in this group of patients does not delay or improve the rates of femoral head survival. Cite this article: Bone Joint J 2021;103-B(3):589-596.

National, clinical cohort study of late effects among survivors of acute lymphoblastic leukaemia: the ALL-STAR study protocol

INTRODUCTION

More than 90% of patients diagnosed with childhood acute lymphoblastic leukaemia (ALL) today will survive. However, half of the survivors are expected to experience therapy-related chronic or late occurring adverse effects, reducing quality of life. Insight into underlying risk trajectories is warranted. The aim of this study is to establish a Nordic, national childhood ALL survivor cohort, to be investigated for the total somatic and psychosocial treatment-related burden as well as associated risk factors, allowing subsequent linkage to nation-wide public health registers.

METHODS AND ANALYSIS

This population-based observational cohort study includes clinical follow-up of a retrospective childhood ALL survivor cohort (n=475), treated according to a common Nordic ALL protocol during 2008-2018 in Denmark. The study includes matched controls. Primary endpoints are the cumulative incidence and cumulative burden of 197 health conditions, assessed through self-report and proxy-report questionnaires, medical chart validation, and clinical examinations. Secondary endpoints include organ-specific outcome, including cardiovascular and pulmonary function, physical performance, neuropathy, metabolic disturbances, hepatic and pancreatic function, bone health, oral and dental health, kidney function, puberty and fertility, fatigue, and psychosocial outcome. Therapy exposure, acute toxicities, and host genome variants are explored as risk factors.

ETHICS AND DISSEMINATION

The study is approved by the Regional Ethics Committee for the Capital Region in Denmark (H-18035090/H-20006359) and by the Danish Data Protection Agency (VD-2018-519). Results will be published in peer-reviewed journals and are expected to guide interventions that will ameliorate the burden of therapy without compromising the chance of cure.

Optimal approach to the treatment of young adults with acute lymphoblastic leukemia in 2020

Akin to the introduction of tyrosine kinase inhibitors to Philadelphia chromosome-positive acute lymphoblastic leukemia (ALL), pediatric-based asparaginase-heavy approaches have revolutionized the treatment of young adults with the Philadelphia chromosome-negative subset the past decades. Once again, we are approaching a new era. An era of precision medicine with immunotherapy and other molecularly targeted treatments that offers unique opportunities to customize treatment intensity with or without hematopoietic stem cell transplantation, reduce the burden of toxicities, and combat persistent residual disease. Recently approved agents for refractory/relapsed B-cell precursor ALL include the chimeric antigen receptor-modified T-cells, the anti-CD22 monoclonal antibody-drug conjugate, inotuzumab ozogamicin, and the bispecific anti-CD19 T-cell engager, blinatumomab. These agents are expected to move widely into the frontline setting along with the proteasome inhibitors, bortezomib and carfilzomib, as well as tyrosine kinase inhibitors for Philadelphia-like rearrangements that are especially frequent among young adults. To this add the BH3 mimetics, venetoclax and navitoclax, which are being widely explored in refractory/relapsed as well as frontline settings for B- and T-cell ALL. The promising anti-CD38 monoclonal antibody, daratumumab, is entering the scene of refractory/relapsed T-ALL, whereas the old purine analogue, nelarabine, is being evaluated in a new upfront setting. This review focuses on 2 main questions: How do we optimize frontline as well as salvage ALL treatment of young adults in the 2020s? Not least, how do we address the current burden of serious toxicities unique to young adults?

British OsteoNEcrosis Study (BONES) protocol: a prospective cohort study to examine the natural history of osteonecrosis in older children, teenagers and young adults with acute lymphoblastic leukaemia and lymphoblastic lymphoma

INTRODUCTION

Osteonecrosis is a well-recognised treatment-related morbidity risk in patients diagnosed with acute lymphoblastic leukaemia (ALL) and lymphoblastic lymphoma (LBL), with a high rate of affected patients requiring surgical intervention. Patients may have asymptomatic changes on imaging studies that spontaneously regress, and little is known about the natural history of osteonecrotic changes seen. The main aim of the British OsteoNEcrosis Study (BONES) is to determine the incidence of symptomatic and asymptomatic osteonecrosis in the lower extremities of survivors of ALL or LBL diagnosed aged 10-24 years in the UK at different time points in their treatment. This study also aims to identify risk factors for progression and the development of symptomatic osteonecrosis in this population, as well as specific radiological features that predict for progression or regression in those with asymptomatic osteonecrosis METHODS AND ANALYSIS: BONES is a prospective, longitudinal cohort study based at principal treatment centres around the UK. Participants are patients aged 10-24 years diagnosed with ALL or LBL under standard criteria. Assessment for osteonecrosis will be within 4 weeks of diagnosis, at the end of delayed intensification and 1, 2 and 3 years after the start of maintenance therapy. Assessment will consist of MRI scans of the lower limbs and physiotherapy assessment. Clinical and biochemical data will be collected at each of the time points. Bone mineral density data and vertebral fracture assessment using dual-energy X-ray absorptiometry will be collected at diagnosis and annually for 3 years after diagnosis of malignancy.

ETHICS AND DISSEMINATION

Ethical approval has been obtained through the Yorkshire and Humber Sheffield Research Ethics Committee (reference number: 16/YH/0206). Study results will be published on the study website, in peer-reviewed journals and presented at relevant conferences and via social media.

TRIAL REGISTRATION NUMBER

NCT02598401; Pre-results.

Asparaginase combined with discontinuous dexamethasone improves antileukemic efficacy without increasing osteonecrosis in preclinical models

Introduction

Combination therapy for acute lymphoblastic leukemia (ALL) is highly effective but results in significant toxicity including osteonecrosis. Asparaginase is known to potentiate both the antileukemic and osteonecrosis-inducing effects of dexamethasone. The schedule of dexamethasone alters osteonecrosis risk. However, the effects of the interaction with asparaginase are unknown when dexamethasone is given on a discontinuous schedule.

Methods

Using the murine model of osteonecrosis, we compared the frequency of osteonecrosis in mice receiving discontinuous dexamethasone (3.5 days/ week) with mice receiving asparaginase and discontinuous dexamethasone. We then tested the effect on antileukemic efficacy using six pediatric ALL xenografts.

Results

The addition of asparaginase to discontinuous dexamethasone did not alter the rate of osteonecrosis compared to dexamethasone alone (7/35 in dexamethasone with asparaginase combination vs. 10/36 in dexamethasone alone, p = 0.62) despite increasing steady-state plasma dexamethasone levels (103.9 nM vs. 33.4 nM, p = 9.2x10^-7). Combination therapy with asparaginase and dexamethasone demonstrated synergistic antileukemic effects across all six xenografts studied.

Conclusions

When discontinuous dexamethasone was given, its anti-leukemic activity synergized with asparaginase but the osteonecrosis-worsening effects of asparaginase (above dexamethasone alone) were not observed. Thus, there is a favorable drug interaction (unchanged toxicity, synergistic efficacy) between discontinuous dexamethasone and asparaginase.