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.