More than 25 000 allogeneic hematopoietic stem cell transplantations (allo-HCTs) are expected to be performed worldwide in 2010, a number that has been increasing yearly. With broadening indications, more options for allo-HCT, and improvement in survival, by 2020 there may be up to half a million long-term survivors after allo-HCT worldwide. These patients have increased risks for various late complications, which can cause morbidity and mortality. Most long-term survivors return to the care of their local hematologists/oncologists or primary care physicians, who may not be familiar with specialized monitoring recommendations for this patient population. The purpose of this article is to describe practical approaches to screening for and managing these late effects, with the goal of reducing preventable morbidity and mortality associated with allo-HCT. (Blood. 2011;117(11):3002-3009)
IntroductionSince the first 3 cases of successful allogeneic stem cell transplantation (allo-HCT) in 1968, the number of allo-HCTs performed annually has increased steadily over the past 3 decades. [1][2][3][4] Since 2007, more allo-HCT procedures have been performed using alternative donor stem cell sources, such as volunteer unrelated donors or cord blood than related donors. [3][4][5] With less early mortality and more widespread use of HCT, the number of long-term survivors will continue to grow. Yet, among long-term survivors after allo-HCT, mortality rates are 4-to 9-fold higher than observed in an age-adjusted general population for at least 30 years after HCT, yielding an estimated 30% lower life expectancy compared with someone who has not been transplanted. Among long-term survivors, the most common causes of excess deaths other than recurrent malignancy are chronic graft-versus-host disease (GVHD), infections, second malignancies, respiratory diseases, and cardiovascular disease (CVD). [6][7][8][9][10][11] This article summarizes the medical late effects observed in long-term allo-HCT survivors to frame our recommendations for evaluation and management. Given that there are no randomized trials testing diagnostic and treatment approaches for late effects within the HCT population and only limited published guidelines, we turned to general medicine studies for guidance, augmented by our personal experiences. Therefore, this article offers practical advice and outlines our personal approaches in monitoring longterm survivors after allo-HCT. Management of chronic GVHD is beyond the scope of this article and is often managed in conjunction with transplantation physicians. 12
Second malignanciesAfter allo-HCT, survivors have an increased risk of developing new solid cancers, with the cumulative incidence ranging from 2% to 6% at 10 years after transplantation. [13][14][15][16][17] A study of 28 874 allo-HCT survivors published in 2009 reported that new solid cancers developed at twice the rate expected in the general population, 13 with the risk increasing over time, reaching 3-fold among patients followed for 15 years or more...