Bone mineral deficits in recipients of hematopoietic cell transplantation: the impact of young age at transplant

International recommendations for screening and preventative practices for long-term survivors of transplantation and cellular therapy: a 2023 update

As hematopoietic cell transplantation (HCT) and cellular therapy expand to new indications and international access improves, the volume of HCT performed annually continues to rise. Parallel improvements in HCT techniques and supportive care entails more patients surviving long-term, creating further emphasis on survivorship needs. Survivors are at risk for developing late complications secondary to pre-, peri- and post-transplant exposures and other underlying risk-factors. Guidelines for screening and preventive practices for HCT survivors were originally published in 2006 and updated in 2012. To review contemporary literature and update the recommendations while considering the changing practice of HCT and cellular therapy, an international group of experts was again convened. This review provides updated pediatric and adult survivorship guidelines for HCT and cellular therapy. The contributory role of chronic graft-versus-host disease (cGVHD) to the development of late effects is discussed but cGVHD management is not covered in detail. These guidelines emphasize special needs of patients with distinct underlying HCT indications or comorbidities (e.g., hemoglobinopathies, older adults) but do not replace more detailed group, disease, or condition specific guidelines. Although these recommendations should be applicable to the vast majority of HCT recipients, resource constraints may limit their implementation in some settings.

International Recommendations for Screening and Preventative Practices for Long-Term Survivors of Transplantation and Cellular Therapy: A 2023 Update

As hematopoietic cell transplantation (HCT) and cellular therapy expand to new indications and international access improves, the number of HCTs performed annually continues to rise. Parallel improvements in HCT techniques and supportive care entails more patients surviving long term, creating further emphasis on survivorship needs. Survivors are at risk for developing late complications secondary to pretransplantation, peritransplantation, and post-transplantation exposures and other underlying risk factors. Guidelines for screening and preventive practices for HCT survivors were originally published in 2006 and then updated in 2012. An international group of experts was convened to review the contemporary literature and update the recommendations while considering the changing practices of HCT and cellular therapy. This review provides updated pediatric and adult survivorship guidelines for HCT and cellular therapy. The contributory role of chronic graft-versus-host disease (cGVHD) to the development of late effects is discussed, but cGVHD management is not covered in detail. These guidelines emphasize the special needs of patients with distinct underlying HCT indications or comorbidities (eg, hemoglobinopathies, older adults) but do not replace more detailed group-, disease-, or condition-specific guidelines. Although these recommendations should be applicable to the vast majority of HCT recipients, resource constraints may limit their implementation in some settings.

Assessing quality and quantity of cortical bone in childhood cancer survivors using anthropometric indices

OBJECTIVES

Evaluate mandibular cortical bone in childhood cancer survivors (CCS) and correlate findings with disease and treatment characteristics.

METHODS

Dental panoramic radiographs of 60 CCS and of 120 age and gender-matched healthy individuals were assessed by two independent observers. Bone was categorized as normal, moderately or severely eroded and its width was calculated at four sites bilaterally. Significant differences were tested using Chi-square and Pearson correlation co-efficient. Possible risk factors were detected by multivariate regression analysis.

RESULTS

Forty five percent of CCS had moderately eroded bone, while 67% of healthy individuals normal bone. Mean width was 3.9 mm in CCS (1.9 mm-6.4 mm) and 2.7 mm in healthy controls (1.4 mm-6 mm). None of the above differences were significant. Survivors diagnosed at a younger age had a five times greater probability of presenting mildly eroded bone.

CONCLUSIONS

No direct effect of antineoplastic treatment on cortical bone could be demonstrated in the current study, underlying the need for more well-designed studies.

Endocrine sequelae of hematopoietic stem cell transplantation: Effects on mineral homeostasis and bone metabolism

Hematopoietic stem cell transplantation (HSCT) is an established therapeutic strategy for the treatment of malignant (leukemia and lymphoma) and non-malignant (thalassemia, anemia, and immunodeficiency) hematopoietic diseases. Thanks to the improvement in patient care and the development of more tolerable conditioning treatments, which has extended the applicability of therapy to the elderly, a growing number of patients have successfully benefited from HSCT therapy and, more importantly, HSCT transplant-related mortality has consistently reduced in recent years. However, concomitantly to long term patient survival, a growing incidence of late HSCT-related sequelae has been reported, being variably associated with negative effects on quality of life of patients and having a non-negligible impact on healthcare systems. The most predominantly observed HSCT-caused complications are chronic alterations of the endocrine system and metabolism, which endanger post-operative quality of life and increase morbidity and mortality of transplanted patients. Here, we specifically review the current knowledge on HSCT-derived side-effects on the perturbation of mineral metabolism; in particular, the homeostasis of calcium, focusing on current reports regarding osteoporosis and recurrent renal dysfunctions that have been observed in a percentage of HSC-transplanted patients. Possible secondary implications of conditioning treatments for HSCT on the physiology of the parathyroid glands and calcium homeostasis, alone or in association with HSCT-caused renal and bone defects, are critically discussed as well.

Bone Health Management After Hematopoietic Cell Transplantation: An Expert Panel Opinion from the American Society for Transplantation and Cellular Therapy

Bone health disturbances commonly occur after hematopoietic cell transplantation (HCT) with loss of bone mineral density (BMD) and avascular necrosis (AVN) foremost among them. BMD loss is related to pretransplantation chemotherapy and radiation exposure and immunosuppressive therapy for graft-versus-host-disease (GVHD) and results from deficiencies in growth or gonadal hormones, disturbances in calcium and vitamin D homeostasis, as well as osteoblast and osteoclast dysfunction. Although the pathophysiology of AVN remains unclear, high-dose glucocorticoid exposure is the most frequent association. Various societal treatment guidelines for osteoporosis exist, but the focus is mainly on menopausal-associated osteoporosis. HCT survivors comprise a distinct population with unique comorbidities, making general approaches to bone health management inappropriate in some cases. To address a core set of 16 frequently asked questions (FAQs) relevant to bone health in HCT, the American Society of Transplant and Cellular Therapy Committee on Practice Guidelines convened a panel of experts in HCT, adult and pediatric endocrinology, orthopedics, and oral medicine. Owing to a lack of relevant prospective controlled clinical trials that specifically address bone health in HCT, the answers to the FAQs rely on evidence derived from retrospective HCT studies, results extrapolated from prospective studies in non-HCT settings, relevant societal guidelines, and expert panel opinion. Given the heterogenous comorbidities and needs of individual HCT recipients, answers to FAQs in this article should be considered general recommendations, with good medical practice and judgment ultimately dictating care of individual patients. Readers are referred to the Supplementary Material for answers to additional FAQs that did not make the core set.

Deletion of the Fanconi Anemia C Gene in Mice Leads to Skeletal Anomalies and Defective Bone Mineralization and Microarchitecture

Fanconi anemia (FA) is a rare genetic disorder associated with a progressive decline in hematopoietic stem cells leading to bone marrow failure. FA is also characterized by a variety of developmental defects including short stature and skeletal malformations. More than half of children affected with FA have radial-ray abnormalities, and many patients have early onset osteopenia/osteoporosis. Although many Fanconi anemia genes have been identified and a molecular pathway defined, the underlying mechanism leading to bone defects remains elusive. To understand the role of FA genes in skeletal development and bone microarchitecture, we evaluated bone physiology during embryogenesis and in adult FancA- and FancC-deficient mice. We found that both FancA^-/- and FancC^-/- embryos have abnormal skeletal development shown by skeletal malformations, growth delay, and reduced bone mineralization. FancC^-/- adult mice present altered bone morphology and microarchitecture with a significant decrease in cortical bone mineral density in a sex-specific manner. Mechanical testing revealed that male but not female FancC^-/- mice show reduced bone strength compared with their wild-type littermates. Ex vivo cultures showed that FancA^-/- and FancC^-/- bone marrow-derived mesenchymal stem cells (_BM MSC) have impaired differentiation capabilities together with altered gene expression profiles. Our results suggest that defective bone physiology in FA occurs in utero and possibly results from altered _BM MSC function. These results provide valuable insights into the mechanism involved in FA skeletal defects. © 2018 American Society for Bone and Mineral Research.

Bone Mineral Density Corrected for Size in Childhood Leukaemia Survivors Treated with Haematopoietic Stem Cell Transplantation and Total Body Irradiation

BACKGROUND

Childhood leukaemia survivors treated with haematopoietic stem cell transplantation and total body irradiation (HSCT-TBI) have multiple risk factors for reduced bone mineral density (BMD) and growth failure; hence, BMD assessment must take body size into consideration. This study aimed to evaluate size-corrected BMD in leukaemia survivors treated with and without HSCT-TBI.

METHODS

Childhood leukaemia survivors treated with HSCT-TBI (n = 35), aged 17.3 (10.5-20.9) years, were compared with those treated with chemotherapy only, (n = 16) aged 18.5 (16.1-20.9) years, and population references. Outcome measures included anthropometric measurements and BMD by dual-energy X-ray absorptiometry. BMD was corrected for size as bone mineral apparent density (BMAD). Statistical analysis was performed by 1- and 2-sample t tests as well as regression analysis (5% significance).

RESULTS

HSCT-TBI survivors were lighter and shorter with reduced spinal heights compared with chemotherapy-only subjects and population references. Compared with population references, HSCT-TBI survivors showed lower BMD standard deviation scores (SDS) (p = 0.008), but no difference in BMAD-SDS, and chemotherapy-only survivors showed no differences in neither BMD-SDS nor BMAD-SDS. All HSCT-TBI participants with BMD-SDS <-2 had BMAD-SDS >-2. BMAD-SDS was negatively associated with age (r = -0.38, p = 0.029) in HSCT-TBI survivors.

CONCLUSIONS

Size-corrected BMD are normal in HSCT-TBI survivors in young adulthood, but may reduce overtime. BMD measurements should be corrected for size in these patients to be clinically meaningful.

Impaired Bone Mineral Density in Pediatric Patients with Chronic Graft-versus-Host Disease

Pediatric allogeneic hematopoietic stem cell transplantation (AHSCT) recipients with chronic graft-versus-host disease (cGVHD) are at high risk for endocrinopathies, particularly impaired bone mineral density (BMD). However, rates of BMD impairment in pediatric AHSCT recipients with cGVHD have not been well documented. We report 33 patients with cGVHD who were referred to the National Institutes of Health (NIH) for the Natural History of Clinical and Biological Factors Determining Outcomes in Chronic Graft-versus-Host Disease Study (NCT 0092235) and underwent formal BMD assessment via dual-energy X-ray absorptiometry (DEXA). Not surprisingly, we found much higher rates of BMD impairment than previously reported for pediatric AHSCT recipients who were not stratified by the presence or absence of cGVHD. Most of these patients (73%) had a z-score ≤-2 in at least 1 anatomic site. Although we expected the rate to be higher than that observed for pediatric AHSCT recipients in studies that did not analyze patients with cGVHD separately, this rate is nonetheless extremely high. Furthermore, the overall rate of occult vertebral compression fractures (VCFs) in our cohort was 17%, and the rate was 23% in patients with at least 1 z-score of ≤-2. The rates of BMD impairment and VCF in our pediatric cohort were significantly higher than those seen in the adult AHSCT recipients who were concurrently enrolled on the same study at the NIH and had similar cGVHD severity. We found that older age at cGVHD diagnosis and a greater number of systemic therapies were associated with occult VCF. Moreover, the intensity of current immunosuppression negatively impacted lumbar spine and total hip BMD in this cohort. Our study, although limited by small patient numbers and lack of a control AHSCT recipient group without cGVHD, indicates that children with cGVHD are at a greater risk for BMD impairment than previously appreciated. Given the rising incidence of cGVHD in AHSCT recipients and our findings, we recommend that pre-AHSCT DEXA be incorporated into routine pediatric pretransplantation screening studies. A baseline DEXA study could facilitate longitudinal monitoring of BMD in children, who may be more susceptible than adults to the negative effects of AHSCT on BMD. In addition, given the high risk of BMD impairment in pediatric AHSCT recipients with cGVHD, such patients should undergo BMD evaluation upon developing cGVHD, with continued monitoring thereafter to allow intervention before progression of the BMD impairment to its severe manifestation, VCF.

Risk of osteoporosis and pathologic fractures in cancer patients who underwent hematopoietic stem cell transplantation: a nationwide retrospective cohort study

Background

Long-term data on post-hematopoietic stem cell transplantation (HSCT) osteoporosis and fracture are limited. This study evaluated the long-term risk of osteoporosis and fracture in cancer patients who underwent HSCT.

Results

The incidence density rate of osteoporosis was 12.5 per 1000 person-years in the HSCT group, which was significantly higher than that in the non-HSCT group (5.65 per 1000 person-years) after adjustment for associated factors and consideration of competing risk factors (adjusted subhazard ratio, 1.48; 95% confidence interval, 1.06–2.07). The incidence density rate of fracture was 4.89 per 1000 person-years in the HSCT group, and the risk of fracture was 1.40 times higher in the HSCT group than in the non-HSCT group (95% confidence interval, 0.83–2.40). The vertebra was the most common site of fracture after HSCT (68.4%). The risk of osteoporosis and fracture significantly increased in post-HSCT patients with both hematological malignancies and solid tumors. Both autologous and allogeneic HSCTs increased the risk of osteoporosis, whereas only autologous HSCT recipients had an increased risk of fracture.

Materials and Methods

This nationwide retrospective cohort study analyzed data from Taiwan's National Health Insurance Research Database. We identified an HSCT group comprising 1040 cancer patients who underwent HSCT during 2000–2008 and a non-HSCT group comprising 4160 propensity score-matched cancer patients who did not undergo HSCT. All patients were followed up until the occurrence of osteoporosis; fracture; December 31, 2011; or withdrawal from the insurance program.

Conclusions

HSCT recipients have an increased risk of osteoporosis.

DIAGNOSIS OF ENDOCRINE DISEASE: Endocrine late-effects of childhood cancer and its treatments

Endocrine complications are frequently observed in childhood cancer survivors (CCS). One of two CCS will experience at least one endocrine complication during the course of his/her lifespan, most commonly as a late-effect of cancer treatments, especially radiotherapy and alkylating agent chemotherapy. Endocrine late-effects include impairments of the hypothalamus/pituitary, thyroid and gonads, as well as decreased bone mineral density and metabolic derangements leading to obesity and/or diabetes mellitus. A systematic approach where CCS are screened for endocrine late-effects based on their cancer history and treatment exposures may improve health outcomes by allowing the early diagnosis and treatment of these complications.

Endocrinopathies, Bone Health, and Insulin Resistance in Patients with Fanconi Anemia after Hematopoietic Cell Transplantation

A number of endocrinopathies have been described after hematopoietic cell transplantation (HCT), but data are limited in patients with Fanconi anemia (FA). We report several endocrine-based disorders in a cohort of 44 patients with FA after HCT compared with both 74 patients who received HCT for hematologic malignancies and with 275 healthy controls. Endocrinopathies assessed included hypothyroidism, hypogonadism, short stature, dyslipidemia, insulin resistance, abnormalities in body composition, and bone health. Most (86%) patients with FA had at least 1 endocrinopathy, with 11% having 3 or more. Hypothyroidism was seen in 57%, hypogonadism in 27%, short stature in 50%, and reduced total body and lumbar spine bone mineral density (BMD) (height adjusted Z-score < -1) in 57% and 21%, respectively. Vitamin D deficiency was seen in 71%. Short stature was associated with younger age at HCT and gonadal failure was associated with older age at HCT. Insulin resistance was associated with increased percent fat mass and increased android/gynoid ratio by dual energy X-ray absorptiometry. Hypothyroidism, short stature, and reduced total body BMD were more prevalent in patients with FA compared with patients with hematologic malignancies. We recommend an assessment before transplantation and close follow-up afterwards to ensure proper clinical management. Future studies should continue to explore the impact of HCT on endocrinopathies in FA patients.

Late Effects Surveillance Recommendations among Survivors of Childhood Hematopoietic Cell Transplantation: A Children's Oncology Group Report

Hematopoietic cell transplantation (HCT) is an important curative treatment for children with high-risk hematologic malignancies, solid tumors, and, increasingly, nonmalignant diseases. Given improvements in care, there are a growing number of long-term survivors of pediatric HCT. Compared with childhood cancer survivors who did not undergo transplantation, HCT survivors have a substantially increased burden of serious chronic conditions and impairments involving virtually every organ system and overall quality of life. This likely reflects the joint contributions of pretransplantation treatment exposures and organ dysfunction, the transplantation conditioning regimen, and any post-transplantation graft-versus-host disease (GVHD). In response, the Children's Oncology Group (COG) has created long-term follow-up guidelines (www.survivorshipguidelines.org) for survivors of childhood, adolescent, and young adult cancer, including those who were treated with HCT. Guideline task forces, consisting of HCT specialists, other pediatric oncologists, radiation oncologists, organ-specific subspecialists, nurses, social workers, other health care professionals, and patient advocates systematically reviewed the literature with regards to late effects after childhood cancer and HCT since 2002, with the most recent review completed in 2013. For the most recent review cycle, over 800 articles from the medical literature relevant to childhood cancer and HCT survivorship were reviewed, including 586 original research articles. Provided herein is an organ system-based overview that emphasizes the most relevant COG recommendations (with accompanying evidence grade) for the long-term follow-up care of childhood HCT survivors (regardless of current age) based on a rigorous review of the available evidence. These recommendations cover both autologous and allogeneic HCT survivors, those who underwent transplantation for nonmalignant diseases, and those with a history of chronic GVHD.

Bone mineral density in children with fanconi anemia after hematopoietic cell transplantation

Fanconi anemia (FA) is an inherited DNA repair disorder associated with short stature and bone marrow failure, usually requiring hematopoietic cell transplantation (HCT). Although low bone mineral density (BMD) has been reported in leukemia patients after HCT, little is known about BMD in FA children after HCT (FA HCT). This study's goals were to compare BMD in FA HCT to BMD in healthy controls and in children who received HCT for hematologic malignancy (cancer HCT), and to test for associations between BMD and risk factors for bone loss. This cross-sectional study included 20 FA HCT, 13 cancer HCT, and 90 healthy controls, age-matched and <18 years old at evaluation. BMD Z-scores for total body (TBMD) and lumbar spine (LBMD) were measured by dual energy x-ray absorptiometry and adjusted for height-for-age Z-score (HAZ). FA HCT had lower mean TBMDHAZ Z-score (by .8 SD) and higher fraction with Z-score ≤ -1 than healthy controls (42% versus 11%). No LBMD deficits were detected. FA HCT and cancer HCT groups did not differ significantly in TBMD or LBMD Z-scores. In FA HCT patients, lower body mass index and lower percent fat were associated with lower BMD. This study highlights the importance of monitoring BMD to optimize bone health in FA patients.

Endocrine Disorders in Childhood Cancer Survivors Treated with Haemopoietic Stem Cell Transplantation

The increasing number of haemopoietic stem cell transplantations (HSCT) taking place worldwide has offered a cure to many high risk childhood malignancies with an otherwise very poor prognosis. However, HSCT is associated with an increased risk of morbidity and premature death, and patients who have survived the acute complications continue to face lifelong health sequelae as a result of the treatment. Endocrine dysfunction is well described in childhood HSCT survivors treated for malignancies. The endocrine system is highly susceptible to damage from the conditioning therapy, such as, alkylating agents and total body irradiation, which is given prior stem cell infusion. Although not immediately life-threatening, the impact of these abnormalities on the long term health and quality of life in these patients may be considerable. The prevalence, risk factors, clinical approaches to investigations and treatments, as well as the implications of ongoing surveillance of endocrine disorders in childhood HSCT survivors, are discussed in this review.