Hematopoietic stem-cell transplantation in systemic sclerosis: an update

PURPOSE OF REVIEW: To provide an overview of recently published work on autologous hematopoietic stem-cell transplantation (HSCT) in patients with systemic sclerosis (SSc).

RECENT FINDINGS: Superiority of HSCT vs. intravenous cyclophosphamide pulses was demonstrated in the randomized controlled American Scleroderma: Cyclophosphamide or Transplantation (SCOT) Trial (n = 75), supporting the results from earlier studies. In the SCOT Trial, total body irradiation was used instead of the nonmyeloablative regimens used in other trials, and considered well tolerated during a follow-up time of 4.5 years. Three small uncontrolled prospective cohorts (n = 4, 14 and 18) and one retrospective analyses (n = 18), using various nonmyeloablative regimens, also showed improvement in skin involvement and lung volumes post-HSCT. Transplant-related toxicity and mortality remain an essential issue in HSCT. High treatment-related mortality was reported in one prospective cohort (n = 18), using alemtuzumab as a conditioning agent. Furthermore, cardiac complications, either treatment or disease related, require special attention. In translational studies, trends are reported in number of regulatory T cells and diversity of T-cell receptor repertoire at baseline and post-HSCT correlating with treatment response.

SUMMARY: There is increasing evidence that patients with rapidly progressive SSc may benefit from HSCT. However, optimal patient selection, pretransplantation workup and posttransplant management, still have to be established.