Bone mineral status after treatment of malignant lymphoma in childhood and adolescence

Osteoporosis in Childhood Cancer Survivors: Physiopathology, Prevention, Therapy and Future Perspectives

Simple Summary

Anti-cancer treatments induced an increase in the childhood cancer survival rate. However, they are responsible for several long-term side effects in childhood cancer survivors, including osteoporosis. Cancer itself, a sedentary lifestyle, and an unhealthy diet might adversely affect bone health. Early identification and adequate management of bone fragility in childhood cancer survivors could be useful to prevent osteoporosis onset and consequently fragility fractures.

Abstract

The improvement of chemotherapy, radiotherapy, and surgical interventions, together with hematopoietic stem cell transplantation, increased childhood cancer survival rate in the last decades, reaching 80% in Europe. Nevertheless, anti-cancer treatments are mainly responsible for the onset of long-term side effects in childhood cancer survivors (CCS), including alterations of the endocrine system function and activity. In particular, the most frequent dysfunction in CCS is a metabolic bone disorder characterized by low bone mineral density (BMD) with increased skeletal fragility. BMD loss is also a consequence of a sedentary lifestyle, malnutrition, and cancer itself could affect BMD, thus inducing osteopenia and osteoporosis. In this paper, we provide an overview of possible causes of bone impairment in CCS in order to propose management strategies for early identification and treatment of skeletal fragility in this population.

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.

Genome-wide Association Studies Reveal Novel Locus With Sex-/Therapy-Specific Fracture Risk Effects in Childhood Cancer Survivors

Childhood cancer survivors treated with radiation therapy (RT) and osteotoxic chemotherapies are at increased risk for fractures. However, understanding of how genetic and clinical susceptibility factors jointly contribute to fracture risk among survivors is limited. To address this gap, we conducted genome-wide association studies of fracture risk after cancer diagnosis in 2453 participants of European ancestry from the Childhood Cancer Survivor Study (CCSS) with 930 incident fractures using Cox regression models (ie, time-to-event analysis) and prioritized sex- and treatment-stratified genetic associations. We performed replication analyses in 1417 survivors of European ancestry with 652 incident fractures from the St. Jude Lifetime Cohort Study (SJLIFE). In discovery, we identified a genome-wide significant (p < 5 × 10^-8 ) fracture risk locus, 16p13.3 (HAGHL), among female CCSS survivors (n = 1289) with strong evidence of sex-specific effects (p_{sex-heterogeneity}  < 7 × 10^-6 ). Combining discovery and replication data, rs1406815 showed the strongest association (hazard ratio [HR] = 1.43, p = 8.2 × 10^-9 ; n = 1935 women) at this locus. In treatment-stratified analyses in the discovery cohort, the association between rs1406815 and fracture risk among female survivors with no RT exposures was weak (HR = 1.22, 95% confidence interval [CI] 0.95-1.57, p = 0.11) but increased substantially among those with greater head/neck RT doses (any RT: HR = 1.88, 95% CI 1.54-2.28, p = 2.4 × 10^-10 ; >36 Gray only: HR = 3.79, 95% CI 1.95-7.34, p = 8.2 × 10^-5 ). These head/neck RT-specific HAGHL single-nucleotide polymorphism (SNP) effects were replicated in female SJLIFE survivors. In silico bioinformatics analyses suggest these fracture risk alleles regulate HAGHL gene expression and related bone resorption pathways. Genetic risk profiles integrating this locus may help identify female survivors who would benefit from targeted interventions to reduce fracture risk. © 2020 American Society for Bone and Mineral Research (ASBMR).

Low bone mineral density in children and adolescents with cancer

Maximizing accumulation of bone mass during childhood and adolescence is essential to attaining optimal peak bone mass. Childhood cancer survivors (CCS) have lower bone mineral density (BMD) than the general population. Chemotherapeutic agents including steroids and radiotherapy can affect BMD. Cancer itself, hormonal insufficiency, a poor nutritional state, and a deficit of physical activities during or after treatment also influence BMD in CCS, resulting in failure to achieve appropriate peak bone mass. Low BMD in childhood and adolescence can lead to osteoporosis in adult life and complications such as bone pain, bone deformity, and fractures. Thus, BMD in CCS should be monitored with appropriate intervention. Adequate intake of calcium and vitamin D and an increase in physical activity are recommended. Timely supplements of hormones are needed in some cases. Some publications have reported that bisphosphonate therapies using pamidronate or alendronate were well tolerated in CCS and helped increase BMD.

Efficacy and safety of denosumab therapy for low bone mineral density in childhood cancer survivors: A report of preliminary experience

BACKGROUND

In childhood cancer survivors, low bone mineral density (BMD) is a bone-related consequence. Efficacy of denosumab, an effective therapy for adult patients with osteoporosis, remains unclear in children. This study aimed to investigate denosumab therapy efficacy for low BMD in childhood cancer survivors.

PROCEDURE

Between January 2014 and January 2018, we monitored lumbar BMD of children with cancer using dual-energy X-ray absorptiometry after completing chemotherapy with a 6-month interval. For patients with low BMD, defined as height-adjusted Z-scores of BMD < -1.5 in this study, calcium carbonate and vitamin D supplements were initially administered. When low BMD continued for at least 6 months, denosumab therapy was introduced. Calcium and vitamin D supplementation were continued in patients on denosumab. We investigated BMD change and adverse effects during denosumab therapy.

RESULTS

During the study period, 20 patients received denosumab treatment. Mean height-adjusted Z-score of BMD before denosumab treatment was -2.68 but increased to -2, -1.96, and -1.33 at 0.5, 1, and 1.5 years after denosumab treatment, respectively (P = .012). In addition, hypocalcemia occurred in 40% (8/20) of patients; three patients had hypocalcemic symptoms with numbness in all four limbs. All hypocalcemic patients, except one patient who died due to relapsed leukemia, recovered well after continuous calcium supplementation.

CONCLUSIONS

Denosumab is an effective treatment for low BMD in childhood cancer survivors. However, the complication of hypocalcemia might develop posttreatment.

Risk factors and surveillance for reduced bone mineral density in pediatric cancer survivors

BACKGROUND

Pediatric cancer survivors are at increased risk of developing low bone mineral density (BMD) due to cancer treatment. This study assessed the yield of screening for low BMD in pediatric-aged cancer survivors as per the Children's Oncology Group Long-Term Follow-Up (COG-LTFU) Guidelines, which recommend screening survivors who received steroids, methotrexate, or hematopoietic cell transplant (HCT).

METHODS

This is a retrospective cohort study of 475 pediatric blood cancer and noncentral nervous system solid tumor survivors screened for low BMD with dual-energy X-ray absorptiometry (DXA) as per the COG-LTFU Guidelines from 2003 to 2010. Risk factors for low BMD (DXA Z-score ≤-2) were evaluated by univariate and multivariate analysis.

RESULTS

The mean DXA Z-score was -0.1 for both whole body and lumbar spine measurements. Among at-risk survivors, 8.2% (39/475) had low BMD. Multivariate analysis of survivors with low BMD showed significant association with male gender (odds ratio [OR] 3.4, 95% confidence interval [CI], 1.3-9.0), exposure to total body irradiation (TBI), cranial, or craniospinal radiation (OR 5.2, 95% CI, 1.8-14.9), and gonadal dysfunction (OR 4.3, 95% CI, 1.4-13.0). Methotrexate exposure was not significantly associated with low BMD. Survivors receiving HCT had a reduced risk of low BMD (OR 0.2, 95% CI, 0.1-0.9).

CONCLUSION

The highest risk factors for low BMD were male gender, exposure to TBI, cranial, or craniospinal radiation, and gonadal dysfunction. Survivors receiving methotrexate or HCT therapy have the lowest risk for low BMD among those screened. Future studies should investigate risk of low BMD for survivors receiving HCT without radiation exposure.

Impairments that influence physical function among survivors of childhood cancer

Children treated for cancer are at increased risk of developing chronic health conditions, some of which may manifest during or soon after treatment while others emerge many years after therapy. These health problems may limit physical performance and functional capacity, interfering with participation in work, social, and recreational activities. In this review, we discuss treatment-induced impairments in the endocrine, musculoskeletal, neurological, and cardiopulmonary systems and their influence on mobility and physical function. We found that cranial radiation at a young age was associated with a broad range of chronic conditions including obesity, short stature, low bone mineral density and neuromotor impairments. Anthracyclines and chest radiation are associated with both short and long-term cardiotoxicity. Although numerous chronic conditions are documented among individuals treated for childhood cancer, the impact of these conditions on mobility and function are not well characterized, with most studies limited to survivors of acute lymphoblastic leukemia and brain tumors. Moving forward, further research assessing the impact of chronic conditions on participation in work and social activities is required. Moreover, interventions to prevent or ameliorate the loss of physical function among children treated for cancer are likely to become an important area of survivorship research.

Validity of anthropometric measurements for characterizing obesity among adult survivors of childhood cancer: A report from the St. Jude Lifetime Cohort Study

BACKGROUND

Childhood cancer survivors (CCSs) are at risk for obesity. The purpose of this project was to determine which clinical measures of body composition are most accurate among CCSs in comparison with dual-energy x-ray absorptiometry (DXA).

METHODS

The agreement between the body mass index (BMI), skinfold percent body fat, and waist-to-height ratio (WHtR) and DXA was evaluated among 1361 CCSs (mean age, 32.4 ± 7.7 years) 10 or more years after the diagnosis. The sensitivity and specificity of BMI, skinfold, and WHtR obesity classifications were calculated with respect to DXA. Log-binomial regression, stratified by sex, was used to evaluate treatment-related factors for misclassification as nonobese by BMI, skinfolds, and WHtR.

RESULTS

The mean body fat values were 23.3% ± 7.7% (males) and 32.3% ± 8.1% (females) for skinfolds and 26.9% ± 7.4% (males) and 38.4% ± 7.7% (females) for DXA. Pearson correlations between skinfolds and DXA were high (R = 0.83 for males, R = 0.84 for females). Skinfolds incorrectly classified 34.5% of obese males and 27.3% of obese females. BMI measures were the least sensitive with false-negative rates of 46.4% (males) and 53.1% (females). Males exposed to abdominal/pelvic radiation were at increased risk for misclassification as nonobese by BMI (relative risk, 1.57; 95% confidence interval, 1.25-1.95). The percentages classified as obese were highest with DXA (males, 63.1%; females, 84.8%) and lowest with BMI (males, 35.7%; females, 39.7%). Although skinfolds and WHtR underestimated the percentage classified as obese in comparison with DXA, the differences were not as large.

CONCLUSIONS

Findings suggest that skinfolds and WHtR are better than BMI for obesity classification in CCSs. Clinicians should be aware of the high risk of misclassifying obese CCSs as nonobese.

Bone mineral density after childhood cancer in 346 long-term adult survivors of childhood cancer

SUMMARY

More than 45 % of long-term childhood cancer survivors (CCS) were diagnosed with osteopenia. Our data suggest that greater awareness for osteopenia is warranted in long-term CCS, especially in survivors who are older than 30 years, male, and underweight and were treated with cranial-spinal radiotherapy and/or steroids.

INTRODUCTION

Osteopenia is a potential complication of childhood cancer treatment, but the magnitude of this problem in survivors is unknown. We examined (determinants of) bone mineral density (BMD) status in long-term survivors of adult childhood cancer.

METHODS

This retrospective single-centre cohort study included 346 subjects with the most common types of childhood cancer. Subjects had a median age at diagnosis of 7.0 years (range 0.1-16.8 years), a median age at follow-up of 24.5 years (range 18.0-47.6 years) and a median follow-up time of 16.7 years (range 5.6-39.9 years). Total body BMD (BMDTB) and BMD of the lumbar spine (BMDLS) were measured by dual X-ray absorptiometry. Osteopenia was defined as BMD standardized deviation score (SDS) below -1.

RESULTS

Survivors had a lower BMDTB and BMDLS (mean SDS -0.55; p<0.001 and -0.30; p<0.001, respectively) as compared to healthy peers. Osteopenia (BMDTB and/or BMDLS) was present in 45% of the survivors. Multivariate logistic regression analyses identified age at diagnosis<12 years, age>30 years at follow-up, male gender, underweight at follow-up and treatment with cranial-spinal radiotherapy or prednisone as independent prognostic factors for osteopenia.

CONCLUSIONS

This large cohort of childhood cancer survivors identified osteopenia in 45% of CCS. This indicates that greater awareness is warranted, especially in survivors who are older than 30 years, male, have underweight and were treated with cranial-spinal radiotherapy and/or steroids.

Bone mineral density, thyroid function, and gonadal status in young adult survivors of childhood cancer

Introduction

During the last years, changes in the diagnosis and treatment have caused a significant increase of the number of young adults who experienced cancer in childhood. This enlarging population is affected by many health problems, including multiple hormone deficiencies and bone mineral deficits. This is the first polish study assessing bone mineral density and endocrine status in young adult cancer survivors.

Material and methods

A total of 76 long-term survivors treated for pediatric cancer were identified. The mean age at the time of study was 24.1 ±3.5 years. Bone mineral density and TSH, fT3, fT4, FSH, LH, estradiol and testosterone level were assessed for each patient.

Results

Nine subjects were diagnosed with subclinical hypothyroidism. We found higher level of TSH in the study group, in comparison with control group (p = 0.015). Eighteen patients had increased level of FSH. In the study group higher number of patients with high FSH level was found in comparison with the control group (p = 0.049). A low BMD was observed in 7 patients whereas mild BMD deficits were found in 19 participants.

Conclusions

In conclusion, our data show that young adult cancer survivors might experienced various hormonal problems including low bone mass, thyroid impairment and gonadal dysfunction. Some of the patients required treatment, but they were not diagnosed before this study. There is the lack of proper clinical assessment among adult childhood cancer survivors in Poland. Therefore, we demonstrated the need for a comprehensive plan for longitudinal follow-up for late effects in these population.

Bone mineral density in pediatric survivors of Hodgkin and non-Hodgkin lymphomas

PURPOSE

To assess skeletal mass in survivors of childhood Hodgkin disease (HD) and non-Hodgkin lymphoma (NHL) 1-5 years after treatment, and to identify potential risk factors influencing bone mineral density (BMD).

PATIENTS/METHODS

This cross-sectional study was conducted in a cohort of 43 survivors (HD=31; NHL=12); mean age: 16.21 ± 4.4. Total body bone mineral content (TBMC) and density (TBBMD), and lumbar spine density (LSBMD) were determined using dual-energy X-ray absorptiometry.

RESULTS

Three of all 43 patients developed low BMD. No significant differences in height, weight, and/or BMD Z-scores were found between HD and NHL survivors, children who received and did not receive radiotherapy, and the groups with different chemotherapeutic blocks. No differences were noted between the Z-scores of BMC (mean ± SD: 0.31 ± 1.29 vs. -0.089 ± 0.61, p=0.165), TBBMD (mean ± SD: -0.32 ± 1.21 vs. -0.27 ± 0.91, p=0.76), or the LSBMD (mean ± SD: -0.183 ± 1.54 vs. -0.17 ± 0.87, p=0.637) in subgroups, in accordance with time after therapy (subgroup I<2 years and subgroup II>2 years after treatment). In HD survivors, age at diagnosis only affected the TBBMD Z-score (a decrease of 0.127 in total BMD Z-score per each year, R²=0.999, p<0.001).

CONCLUSIONS

Childhood lymphoma survivors demonstrate no significant deficits in bone mass and tend to maintain their BMD within the normal range when presenting during one to five years' follow-up. However, this specific group requires longitudinal investigation to assess the pattern of peak bone mass achievement and the risk of future bone loss.

Bone mineral density deficits and fractures in survivors of childhood cancer

Although substantial increases in survival rates among children diagnosed with cancer have been observed in recent decades, survivors are at risk of developing therapy-related chronic health conditions. Among children and adolescents treated for cancer, acquisition of peak bone mass may be compromised by cancer therapies, nutritional deficiencies, and reduced physical activity. Accordingly, failure to accrue optimal bone mass during childhood may place survivors at increased risk for deficits in bone density and fracture in later life. Current recommendations for the treatment of bone density decrements among cancer survivors include dietary counseling and supplementation to ensure adequate calcium and vitamin D intake. Few strategies exist to prevent or treat bone loss. Moving forward, studies characterizing the trajectory of changes in bone density over time will facilitate the development of interventions and novel therapies aimed at minimizing bone loss among survivors of childhood cancer.

Bone mineral density deficits in childhood cancer survivors: Pathophysiology, prevalence, screening, and management

As chemotherapy and other sophisticated treatment strategies evolve and the number of survivors of long-term childhood cancer grows, the long-term complications of treatment and the cancer itself are becoming ever more important. One of the most important but often neglected complications is osteoporosis and increased risk of fracture during and after cancer treatment. Acquisition of optimal peak bone mass and strength during childhood and adolescence is critical to preventing osteoporosis later in life. However, most childhood cancer patients have multiple risk factors for bone mineral loss. Cancer itself, malnutrition, decreased physical activity during treatment, chemotherapeutic agents such as steroids, and radiotherapy cause bone mineral deficit. Furthermore, complications such as growth hormone deficiency and musculoskeletal deformity have negative effects on bone metabolism. Low bone mineral density is associated with fractures, skeletal deformity, pain, and substantial financial burden not only for childhood cancer survivors but also for public health care systems. Thus, it is important to monitor bone health in these patients and minimize their risk of developing osteoporosis and fragility fractures later in life.

Time-dependent alterations in growth and bone health parameters evaluated at different posttreatment periods in pediatric oncology patients

Bone mineral density (BMD) and anthropometric measurements in pediatric cancer patients were evaluated and compared at early and late posttreatment periods. Sixty-six pediatric cancer patients who recovered completely following treatment longer than at least a 6-month period were included in the study. Patients were evaluated cross-sectionally and prospectively with regard to anthropometric measurements and BMD twice; the first being at a mean period of 2.62 ± 1.44 years and the second of 6.55 ± 1.71 years after the completion of treatment. Rates of osteoporosis and osteopenia at first or second evaluation were 25.8% and 39.4% or 10.6% and 19.7%, respectively. Mean BMD z-scores were (-1.26) ± 1.12 [(-4.3)-2.0] and (-0.48) ± 1.25 [(-3.30)-3.40] at first and second evaluations, respectively. BMD findings obtained at second evaluation revealed statistically significant recovery compared with those obtained at first evaluation (P = .001). BMD z-scores were significantly lower in patients who received, as opposed to those who did not receive, radiotherapy (RT) at both evaluations. Anthropometric parameters of patients such as height, weight, and body mass index (BMI) were increased at both evaluations compared with values obtained at diagnosis (P < .05). Height standard deviation score (SDS) decreased at first evaluation compared with that measured at diagnosis, whereas it increased at second evaluation. Conversely, weight SDS and BMI SDS increased (P < .05) at first evaluation compared with that measured at diagnosis, whereas they decreased at second evaluation. The authors conclude that early impairments in anthropometric measurements recover in the long term, whereas BMD is continually reduced in children who recovered from cancer.

Is the treatment for childhood solid tumors associated with lower bone mass than that for leukemia and Hodgkin disease?

BACKGROUND

Cancer disease and its therapy (e.g., chemotherapeutic agents such as glucocorticoids, methotrexate, antymetabolities, cranial and local irradiation) may severely disturb normal growth, bone mineral acquisition, and skeletal development because most individuals go through the stages of rapid growth when childhood cancer is diagnosed.

PROCEDURES

To identify factors associated with reduced bone mineral density (BMD) in survivors of childhood cancer the authors examined 114 patients (70 males) who had been treated for acute lymphoblastic leukemia (ALL; n = 43), Hodgkin disease (HD; n = 35), and solid tumors (ST; n = 36) twice. Median age at diagnosis was 8.4 years; at the consecutive examinations it was 12.8 and 16.3 years, respectively. To assess bone density we used dual-energy x-ray absorptiometry (DXA).

RESULTS

In the first examination, patients with a history of steroid therapy had higher total and spine BMD and higher BMI (body mass index) than those who were not given steroids. At the end of the follow-up, no differences were found in BMD between subgroups, although BMI was still higher in both ALL and HD patients than in those with ST.

CONCLUSIONS

Patients treated for solid tumors have reduced bone mass. Low BMI and local irradiation seem to be the factors responsible for reduced BMD in children treated for ST. The use of steroids does not disturb bone mass accumulation in patients treated for childhood malignancies. However, a long-term effect of cancer treatment on osteoporosis risk remains to be determined.

Vitamin D status and bone biomarkers in childhood cancer

Early detection of abnormalities in bone turnover may be facilitated by assessing biomarkers of bone metabolism including vitamin D status. In many children with cancer, biomarkers of bone formation (osteocalcin, bone specific alkaline phosphatase and carboxy-(or N terminal) propeptide of type 1 procollagen) were observed to be suppressed, while bone resorption was elevated as measured by serum cross-linked (or C-terminal) telopeptide of type 1 collagen. Insulin-like growth factor 1, which stimulates bone formation, may be suppressed indirectly indicating a growth hormone insufficiency. Leptin may also play a role in bone remodeling as hyperleptinemia has been observed in association with acute lymphoblastic leukemia. Evaluation of bone status using such biomarkers is complicated by the lack of universally accepted reference values and the variation by age, gender, or pubertal status. Etiologic factors contributing to the observed skeletal morbidities include disease process, chemotherapy (drugs such as glucocorticoids and methotrexate) and radiotherapy. Other factors common to children with cancer, such as chronic inflammation, dietary changes and physical inactivity, must also be taken into account. The current evidence for abnormalities in biomarkers of vitamin D status and bone turnover will be the focus of this review of published studies.

Osteonecrosis in children and adolescents with cancer

Osteonecrosis is recognized increasingly as a complication of the treatment of cancer in young people, especially those with acute lymphoblastic leukemia and non-Hodgkin lymphoma, reflecting a probable pathogenetic role of steroid therapy. Children >/=10 years of age and Whites are at particular risk, and genetic predispositions have been identified. The disorder affects weight-bearing joints predominantly. It is commonly bilateral and multi-articular. Treatment options include both surgical and non-surgical interventions.

Bisphosphonate therapy for reduced bone mineral density during treatment of acute lymphoblastic leukemia in childhood and adolescence: a report of preliminary experience

BACKGROUND

Osteopenia is a common consequence of the treatment of acute lymphoblastic leukemia (ALL) in children and adolescents, due predominantly to glucocorticosteroid therapy. The pathogenesis relates to an imbalance of resorption over formation of bone.

METHODS

Alendronate (Fosamax), an inhibitor of osteoclastic bone resorption, was administered for at least 6 months to 15 children with ALL during maintenance chemotherapy, after the diagnosis of osteopenia/osteoporosis by dual energy x-ray absorptiometry. The height velocity was also measured during the administration of alendronate and again 2 years later.

RESULTS

Areal bone mineral density Z scores of the lumbar spine had a median value of -1.32 before administration of alendronate and a median gain of +0.64, with 14/15 children showing improvement. There was no adverse effect of alendronate on height velocity, and the drug was well tolerated with no short-term toxicity.

CONCLUSIONS

This preliminary experience suggests a potential value in the use of alendronate for the treatment of osteopenia/osteoporosis in children with ALL and points to the need for a randomized controlled trial of this intervention.