Post-transplant lymphoproliferative disease (PTLD) is a serious complication occurring as a consequence of immunosuppression in the setting of allogeneic hematopoietic stem cell transplantation (alloHSCT) or solid organ transplantation (SOT). The majority of PTLD arises from B-cells, and Epstein–Barr virus (EBV) infection is present in 60–80% of the cases, revealing the central role played by the latent infection in the pathogenesis of the disease. Therefore, EBV serological status is considered the most important risk factor associated with PTLDs, together with the depth of T-cell immunosuppression pre- and post-transplant. However, despite the advances in pathogenesis understanding and the introduction of novel treatment options, PTLD arising after alloHSCT remains a particularly challenging disease, and there is a need for consensus on how to treat rituximab-refractory cases. This review aims to explore the pathogenesis, risk factors, and treatment options of PTLD in the alloHSCT setting, finally focusing on adoptive immunotherapy options, namely EBV-specific cytotoxic T-lymphocytes (EBV-CTL) and chimeric antigen receptor T-cells (CAR T).

The clearance of malignant clonal cells significantly correlates with clinical outcomes in many hematologic malignancies. Accurate and high throughput tools for minimal residual disease (MRD) detection are needed to overcome some drawbacks of standard molecular techniques; such novel tools have allowed for higher sensitivity analyses and more precise stratification of patients, based on molecular response to therapy. In this review, we depict the recently introduced digital PCR and next-generation sequencing technologies, describing their current application for MRD monitoring in lymphoproliferative disorders. Moreover, we illustrate the feasibility of these new technologies to test less invasive and more patient-friendly tissues sources, such as “liquid biopsy”.

In IgM monoclonal gammopathies MYD88^L265P is a prognostic and predictive biomarker of therapy response. MYD88^L265P detection is mainly performed by allele-specific quantitative PCR (ASqPCR), however recently, droplet digital PCR (ddPCR) has been proved to be suitable for MYD88^L265P screening and minimal residual disease monitoring (MRD). This study compared ASqPCR and ddPCR to define the most sensitive method for MYD88^L265P detection in bone marrow (BM), peripheral blood (PB) sorted or unsorted CD19+ cells, and in plasma cell-free DNA (cfDNA). Overall, the analysis showed a good concordance rate (74%) between the two methods, especially in BM samples, while discordances (26%) were mostly in favor of ddPCR (ddPCR+ vs. ASqPCR-) and were particularly evident in samples with low mutational burden, such as PB and cfDNA. This study highlights ddPCR as a feasible approach for MYD88^L265P detection across different specimen types (including cfDNA). Interestingly, its high sensitivity makes CD19+ selection dispensable. On the other hand, our results showed that MYD88^L265P detection on PB samples, especially with ASqPCR, is suboptimal for screening and MRD analysis. Finally, significantly different MYD88^L265P mutational levels observed between Waldenström Macroglobulinemia and IgM monoclonal gammopathy of undetermined significance patients suggest the need for further studies in order to identify possible correlations between mutational levels and risk of progression to Waldenström.

Background. Bendamustine is a cytotoxic alkylating drug with a broad range of indications as a single agent or in combination therapy in lymphoid neoplasia patients. However, its tolerability in elderly patients is still debated. Methods: An observational, retrospective study was carried out; patients with chronic lymphocytic leukemia (CLL) or lymphoma, aged ≥ 65 years old, treated with bendamustine-based regimens in first or subsequent lines between 2010 and 2020 were considered eligible. Results: Overall, 179 patients aged ≥ 65 years were enrolled, 53% between 71 and 79 years old. Cumulative Illness Rating Scale (CIRS) comorbidity score was ≥6 in 54% patients. Overall survival (OS) at 12 months was 95% (95% confidence interval [CI]: 90–97%); after a median follow up of 50 months, median OS was 84 months. The overall response rate was 87%, with 56% complete responses; the median time to progression (TTP) was 61 months. The baseline factors affecting OS by multivariable analysis were sex, histological diagnosis, renal function, and planned bendamustine dose, while only type of lymphoma and bendamustine dose impacted on TTP. Main adverse events were neutropenia (grade ≥ 3: 43%) and infections (any grade: 36%), with 17% of patients requiring hospital admission. Conclusions: The responses to bendamustine, as well as survival, are relevant even in advanced age patients, with a manageable incidence of acute toxicity.

Hepatitis B virus reactivation (HBVr) can develop in HBV surface antigen (HBsAg) positive or HBsAg-negative and anti-hepatitis B core antigen antibodies (anti-HBc) positive (past HBV infection) patients receiving immuno-chemotherapy for hematological malignancies. A higher rate of HBVr is associated with the use of rituximab (R) in patients with past HBV infection, thus justifying an antiviral prophylaxis. In this study we evaluated the incidence of HBVr in a real-life cohort of 362 anti-HBc-positive subjects affected by non-Hodgkin lymphoma (NHL), mainly receiving lamivudine (LAM) prophylaxis (93%) and all undergoing a R-containing regimen. A retrospective, multicenter, observational study was conducted in 4 Italian Hematology Departments. The primary endpoint was the incidence of virologic (HBV DNA-positive), serologic (HBsAg-positive) and clinical (ALT increase > 3 × upper limit of normal) HBVr, which occurred in five, four and one patients, respectively, with a total HBVr rate of 1.4%. None of them had to discontinue the chemotherapy program, while two patients required a delay. Treatment-related adverse events (AEs) were reported during LAM prophylaxis in three patients (0.9%). In conclusion, this study confirms the efficacy and safety of LAM prophylaxis in anti-HBc-positive patients undergoing R-containing regimens.

Background/Objectives. Recent evidence underscores the prognostic and classificatory relevance of somatic mutations in myelodysplastic neoplasms (MDSs) and acute myeloid leukemia (AML). Methods. This prospective study assessed gene mutation dynamics via next-generation sequencing (NGS) in 84 MDS/AML patients treated with intensive chemotherapy or hypomethylating agents plus venetoclax. Results. At diagnosis, 95% had somatic mutations detected by NGS, while only 29% had a measurable residual disease (MRD) marker with qPCRs. NGS at complete remission (CR) was performed in 56/71 patients who achieved CR; 59% had persisting mutations, mostly in DNMT3A, TET2, and ASXL1 (DTA mutations). Mutations’ persistence in CR was linked to a shorter relapse-free survival (RFS; median 8 months vs. not reached, HR 4.41, 95% CI 1.69–11.49; p = 0.002) and overall survival (OS; 2-year OS: 51.5% vs. 88%, HR 4.02, 95% CI 1.39–11.65; p = 0.001). Combining NGS and multiparameter flow cytometry (MFC) for MRD detection, we divided patients into three groups with distinct RFS (NGS−/MFC−, NGS−/MFC+, or NGS+/MFC− and NGS+/MFC+), with double-negative patients displaying the best RFS (p < 0.001). In the multivariate analysis, NGS and MFC MRD+ were independent predictors of RFS. Conclusions. This real-world study confirms the added prognostic role of NGS in MRD detection on RFS, particularly when combined with MFC. This approach may improve risk stratification and guide treatment decisions.