Researchers Identify Risk Factors for PTLD and Related Mortality

In a study, researchers examined potential risk factors for the incidence of and the mortality due to post-transplant lymphoproliferative disease (PTLD) in a cohort of 1,184 patients who had undergone allogeneic hematopoietic cell transplantation (alloHCT). All patients were predisposed to PTLD because their graft-versus-host disease (GVHD) prophylaxis included antithymocyte globulin, the researchers noted.

The authors described PTLD as “a potentially serious complication that occurs following hematopoietic cell transplantation where B cells transformed by Epstein-Barr virus (EBV) proliferate uncontrollably.” While risk factors for the incidence have been established, they noted that the risk factors for PTLD-related mortality are not fully understood.

They reported a PTLD incidence of 9.0% and a PTLD-related mortality incidence of 1.1%. In multivariate analysis, risk factors for PTLD incidence were donor-positive and recipient-negative EBV serostatus (subhazard ratio [SHR]=3.3; P=0.002). Other risk factors included:

  • donor other than an HLA-matched sibling donor (SHR=1.7; P=0.029)
  • total body irradiation (SHR=3.3; P=0.008)
  • absence of GVHD (SHR=3.3; P<0.001)

The only risk factor for the mortality due to PTLD among all patients was the mismatched EBV serostatus. Risk factors for only PTLD-related mortality, however, were marrow graft (compared to blood stem cells, SHR=22.8; P<0.001) and extralymphatic involvement (SHR=14.6; P<0.001).

“Interestingly, whereas the absence of GVHD was a risk factor for PTLD incidence, there was a trend toward the presence of GVHD being a risk factor for PTLD mortality (SHR=4.2; P=0.093),” the authors noted.

The authors concluded that, while some risk factors for the incidence of PTLD are identical to the risk factors for the mortality due to PTLD (such as donor and recipient serostatus), other risk factors are disparate (such as total body irradiation).