ABSTRACT Introduction: Allogeneic hematopoietic stem cell transplantation offers the opportunity for extended survival in patients with Hodgkin's and non-Hodgkin lymphomas who relapsed after, or were deemed ineligible for, autologous transplantation. This study reports the cumulative experience of a single center over the past 14 years aiming to define the impact of patient, disease, and transplant-related characteristics on outcomes. Methods: All patients with histologically confirmed diagnosis of Hodgkin's or non-Hodgkin lymphomas who received allogeneic transplantation from 2000 to 2014 were retrospectively studied. Results: Forty-one patients were reviewed: 10 (24%) had Hodgkin's and 31 (76%) had non-Hodgkin lymphomas. The median age was 50 years and 23 (56%) were male. The majority of patients (68%) had had a prior autologous transplantation. At the time of allogeneic transplantation, 18 (43%) patients were in complete and seven (17%) were in partial remission. Most (95%) patients received reduced-intensity conditioning, 49% received matched sibling donor grafts, 24% matched-unrelated donor grafts, and 27% received double umbilical cord blood grafts. The 100-day treatment-related mortality rate was 12%. After a median duration of follow up of 17.1 months, the median progression-free and overall survival was 40.5 and 95.8 months, respectively. On multivariate analysis, patients who had active disease at the time of transplant had inferior survival. Conclusions: Allogeneic transplantation results extend survival in selected patients with relapsed/refractory Hodgkin's and non-Hodgkin lymphomas with low treatment-related mortality. Patients who have active disease at the time of allogeneic transplantation have poor outcomes.

Background: Serum lactate dehydrogenase is a non-specific marker for lymphoma whose prognostic significance is well established for both indolent and aggressive lymphomas at the time of diagnosis. The performance characteristics of this enzyme in predicting relapse in patients with diffuse large B-cell lymphoma has not been well studied. Methods: This study compared serum lactate dehydrogenase levels in 27 patients with diffuse large B-cell lymphoma who relapsed after sustaining a complete response versus 87 patients who did not relapse. For relapsed patients, the serum lactate dehydrogenase level at relapse was compared with the level three months before (considered baseline). For non-relapsed patients, the last two levels during follow-up were compared. For statistical analysis the T-test was used to compare differences in mean values between groups. The sensitivity, specificity, positive and negative predictive values for serum lactate dehydrogenase in detecting relapse compared to confirmatory imaging were calculated. Results: At relapse, only 33% patients had increases in serum lactate dehydrogenase above the upper limit of normal. The mean increase was 1.2-fold above the upper limit of normal for relapsed vs. 0.83 for those who did not relapse (p-value = 0.59). The mean increase in serum lactate dehydrogenase, from baseline, was 1.1-fold in non-relapsed vs. 1.3 in relapsed patients (p-value = 0.3). The likelihood ratio of relapse was 4.65 for patients who had 1.5-fold increases in serum lactate dehydrogenase above baseline (p-value = 0.03). The sensitivity, specificity, positive and negative predictive values of 1.5-fold increases for detecting relapse, compared to clinical and imaging findings were 0.18, 0.95, 0.55, and 0.79, respectively. Conclusion: A 1.5-fold increase in serum lactate dehydrogenase, over a period of 3 months, is associated with increased likelihood of relapse from diffuse large B-cell lymphoma.

DNA methylation and other epigenetic phenomena appear to be relevant in the pathogenesis of several malignant disorders. DNA methyltransferases add methyl groups to cytosine-phosphate-guanine (CpG) islandsleading to gene promoter silencing. The DNA methyltransferases inhibitors azacitidine and decitabine have anti-tumor activity against a broad range of malignancies, but have been investigated mostly in myelodysplastic syndrome. In addition, these agents have immunomodulatory effects that are under investigation in the allogeneic stem cell transplantation scenario. Both drugs have been used in the perioperative period of allogeneic transplantations with varying degrees of success. It has been hypothesized that low dose azacitidine may increase the graftversus-leukemia effect and have a role in the maintenance of remission after allogeneic transplantation for myeloid leukemias. It is also intriguing that this favorable effect might occur while mitigating graft-versus-host disease. Here we present a review of the rapidly growing field of epigenetic manipulation using hypomethylating agents in allogeneic transplantation.