Joseph P. Uberti

Diffuse large B-cell lymphoma (DLBCL) is a heterogeneous disease. B-cell receptor (BCR) pathway is essential for malignant B-cell growth, survival, and proliferation. Various immune cells, including T-cells and macrophages in the tumor microenvironment (TME) contribute to tumor cell survival and pathogenesis of chemo-resistance. The presence of many targets on the malignant B-cells and in the TME has led to emergence of novel therapeutic agents. Stem cell transplant is the oldest treatment modality leveraging immune system in DLBCL. Subsequently, CD20 targeting monoclonal antibody and chimeric antigen receptor (CAR) T-cell therapy changed the treatment landscape of DLBCL. Recently, multiple novel immunotherapeutic agents have been added in the armamentarium for the management of DLBCL, and many are under development. In this review article, we will review latest updates of immunotherapeutic agents in the management of DLBCL.

A head-to-head comparison of outcomes of unrelated donor allogeneic peripheral blood stem cell transplantation for AML between reduced intensity conditioning (RIC) and myeloablative conditioning (MAC) regimens using thymoglobulin for GVHD prophylaxis is limited. We evaluated outcomes of 122 AML patients who received either busulfan (Bu)/fludarabine (Flu)/low-dose total body irradiation (TBI) as RIC (n = 64, 52%) or Bu/Flu as MAC (n = 58, 48%), and thymoglobulin 4.5 mg/kg total dose between day − 3 to − 1 for GVHD prophylaxis. Grades III–IV acute GVHD (aGVHD) was lower with Bu/Flu/TBI compared with Bu/Flu (6.2% vs 26.1%, p = 0.009). At 1 year, Bu/Flu/TBI was associated with similar chronic GVHD (41.2% vs 44.8%, p = 0.75), OS (61.9% vs 56.9%, p = 0.69), relapse rate (29.9% vs 20.7%, p = 0.24), relapse-free survival (52.8% vs 50%, p = 0.80), non-relapse mortality (17.4% vs 29.3%, p = 0.41), and GVHD-free relapse-free survival (24.2% vs 27.5%, p = 0.80) compared with Bu/Flu. Multivariable analysis did not reveal any difference in outcomes between both regimens. In summary, thymoglobulin at 4.5 mg/kg did not have any adverse impact on survival when used with RIC regimen. Both Bu/Flu/TBI and Bu/Flu conditioning regimens yielded similar survival.

E18540 Background: In spite of the fact G-CSF has been used post stem cell transplant (SCT) to accelerate neutrophil engraftment its use post allogeneic SCT remains controversial. ASCO does not recommend its use after allogeneic SCT. To further evaluate the effectiveness of its use, we compared outcomes in pts who underwent related and unrelated peripheral blood SCT(PBSCT) either with or without the use of G-CSF post SCT. Methods: This is a retrospective study comparing early outcomes in pts who received G-CSF starting on day + 6 post SCT until engraftment with pts who did not receive a planned course of G-CSF. Pts who underwent Allogeneic PBSCT between 2012-2014 at our institution were included. Pts who received marrow, haploidentical or cord blood transplants were excluded. Associations with survival outcomes were assessed by univariable and multivariable Cox proportional regression models. Results: A total of 162 patients were evaluated. Sixty-five pts received G-CSF post SCT and 97 did not. The only difference between the two groups was that more pts in the G-CSF group received myeloablative-conditioning (MAC) regimen (78% vs. 55%, p = 0.008). Other pt characteristics were not significantly different. Length of hospital stay was significantly lower in the G-CSF group (24 vs. 27 days P = 0.002). Pts who received G-CSF had earlier neutrophil engraftment (median, days 11 vs. 14 p = < 0.001). The median day of platelet engraftment was 15 days in both groups. There was no significant difference between the 2 groups in re-admissions in the first 100 days, and the incidence of acute or chronic GVHD. In multivariate analysis use of G-CSF did not significantly impact non- relapse mortality, relapse free survival and overall survival. However, relapse rate was significantly lower in G-CSF group in multivariable analysis (hazards ratio = 0.44, p = 0.03). Conclusions: Use of G-CSF post allogeneic PBSCT is associated with earlier neutrophil engraftment, shorter hospital stay and a suggestion of a reduced relapse rate after PBSCT. Our experience suggests that use of G-CSF (on average for approximately 5 days) in this setting is cost effective as it reduces hospitalization duration without adversely impacting post-transplant outcomes.

Purpose Although fluoroquinolone prophylaxis is frequently utilized in autologous hematopoietic stem cell transplant (AHSCT) patients, its impact on morbidity and mortality is uncertain. This study investigates the role of quinolone prophylaxis after AHSCT in recent years. Methods We conducted a retrospective review of 291 consecutive adult patients who underwent AHSCT for malignant disorders, between June 2013 and January 2015. Outcomes were compared between patients who received norfloxacin prophylaxis and those who did not. The endpoints were mortality during prophylaxis and at 100 days after transplant, frequency of ICU admissions, and incidence and type of bacteremia. Results Of 291 patients, 252 patients received norfloxacin prophylaxis and 39 patients did not. The mortality during prophylaxis and at 100 days as well as the median number of days of hospitalization following AHSCT did not differ between the two groups. No differences were noted in the frequency of ICU admission, incidence of septic shock, and duration of ICU stay. Patients who did not receive prophylaxis had a significantly higher rate of neutropenic fever (97%) than patients who received prophylaxis (77%) (p = 0.005). The patients with prophylaxis demonstrated a significantly higher rate of gram-positive bacteremia as compared to those without prophylaxis (p = 0.002). Frequency of Clostridium difficile infection was similar during and post-prophylaxis. More antibiotic use was noted among patients without prophylaxis [97%; median 9 (range, 5–24) days] compared to patients with prophylaxis [79%; median 7 (range, 3–36) days, p = 0.04]. Conclusion Although fluoroquinolone prophylaxis reduced the incidence of neutropenic fever and antibiotic use in AHSCT, it did not alter mortality or morbidity.

A multistate model is more complicated than competing risk models and is composed of a finite number of states and transitions between states. Unlike competing risk models, this model has the ability to assess the effect of occurrence order of time-to-event data. Pleural effusion (PE) is a severe complication that often occurs after allogeneic hematopoietic stem cell transplantation (HSCT). Many patients develop PE during the first 100 days after allogeneic HSCT, and graft-versus-host disease (GVHD) occurs either before or after the development of PE, implying that the occurrence order of PE and GVHD (i.e., PE after GVHD vs. GVHD after PE) would influence on the incidence, risk factors, and mortality of PE. One can use either Cox proportional models or competing risk models to evaluate these values, but neither method is able to incorporate the occurrence order of incidence into the model. To resolve this difficulty, we developed a multistate model describing several possible events and event-related dependencies and applied to a retrospective study of 606 patients, including eight covariates.

We retrospectively compared clinical outcomes in 1593 T-replete unrelated donor (URD) marrow transplant recipients with AML, MDS and CML who received myeloablative conditioning regimens of either BU and CY (BuCy), standard-dose Cy/TBI (1000–1260 cGy) or high-dose Cy/TBI (1320–1500 cGy). Subjects were drawn from patients transplanted between 1991 and 1999 facilitated by the National Marrow Donor Program. Patients who received high-dose Cy/TBI regimens were slightly younger, more likely to receive a mismatched transplant and to have intermediate or advanced disease compared with patients in the BuCy or standard-dose TBI group. Neutrophil recovery was significantly higher in the standard-dose CY/TBI group compared with the high-dose Cy/TBI or BuCy group. Patients who received the high-dose Cy/TBI regimen had an increased risk of developing grades III–IV aGVHD when compared with the control group who received BuCy (P=0.011). OS, disease-free survival (DFS), TRM and relapse were not significantly different between any of the regimens. We conclude that BuCy, standard-dose and high-dose Cy/TBI regimens have equivalent efficacy profiles for OS, DFS, TRM and relapse risk in patients undergoing T-replete URD marrow transplantation for AML, CML and MDS.