Post-transplant lymphomas: a 20-year epidemiologic, clinical and pathologic study in a single center

Background and Objectives. To study the incidence, clinical presentation, p athologic features and outcome of post-transplant lymphomas (PTL) during th e past 20 years. Design and Methods. We undertook a descriptive study of all biopsy-proven c ases of rm diagnosed in our hospital from 1979 through 1999. The average an nual incidence rate of PTL was analyzed at 5-year intervals from 1979 to 19 99. Risk ratios were estimated by comparing the incidence of PTL among tran splanted patients with that of lymphoma observed in the general population of the region. Survival analysis was performed at the univariate level usin g the Kaplan Meier technique and at the multivariate level by Cox hazard mo dels. Results. Seventeen of 1,860 transplanted patients developed a PTL (0.9%). T he risk of PTL was calculated to be almost 8-fold higher than the risk of l ymphoma in the general population. The risk was highest among those who had received a heart transplant (RR=35.6). The mean time between transplant an d the diagnosis of PTL was 31 +/- 29 months. Of all PTL, 88% were of B-cell origin and 53% of the cases tested were Epstein-Barr virus (EBV)-positive. The median survival was 24 months. The majority of patients with allograft involvement died within the 2 months following diagnosis (hazard ratio 5.3 ; 95% CI 1.4-20.7). Interpretation and Conclusions. Organ transplantation is a major risk facto r for the development of lymphoma, a disease with a particularly bad progno sis when it develops at the site of the allograft. Early diagnosis and more specific treatment may improve PTL survival. (C) 2001, Ferrata Storti Foun dation.