Accelerated bone mass senescence after hematopoietic stem cell transplantation.

Osteoporosis and avascular necrosis (AVN) are long-lasting and debilitating complica- tions of hematopoietic stem cell transplantation (HSCT). We describe the magnitude of bone loss, AVN and impairment in osteogenic cell compartment fol- lowing autologous (auto) and allogeneic (allo) HSCT, through the retrospective bone damage re- valuation of 100 (50 auto- and 50 allo-HSCT) long- term survivors up to 15 years after transplant. Cur- rent treatment options for the management of these complications are also outlined. We found that auto- and allo-HSCT recipients show accelerated bone mineral loss and micro- architectural deterioration during the first years after transplant. Bone mass density (BMD) at the lumbar spine, but not at the femur neck, may improve in some patients after HSCT, suggesting more pro- longed bone damage in cortical bone. Phalangeal BMD values remained low for even more years, suggesting persistent bone micro-architectural altera- tions after transplant. The incidence of AVN was higher in allo-HSCT recipients compared to auto- HSCT recipients. Steroid treatment length, but not its cumulative dose was associated with a higher in- cidence of bone loss. Allo-HSCT recipients affected by chronic graft versus host disease seem to be at greater risk of continuous bone loss and AVN devel- opment. Reduced BMD and higher incidence of AVN was partly related to a reduced regenerating capacity of the normal marrow osteogenic cell com- partment. Our results suggest that all patients after auto- HSCT and allo-HSCT should be evaluated for their bone status and treated with anti-resorptive therapy as soon as abnormalities are detected.