Solitary plasmacytoma refers to a neoplastic, clonal proliferation of plasma cells forming a single mass. They are divided based on their origin site; solitary bone plasmacytomas originate from the bones, and extramedullary plasmacytomas represent extraosseous tumors. These are rare tumors but carry a risk of transforming to multiple myeloma; thus, optimal management and meticulous follow-up are needed. Their rarity poses a major challenge in conducting large-scale clinical trials, leaving important gaps in evidence regarding best practices. Newer imaging techniques have improved the quality of staging, management decisions, and outcomes. Radiation still has a significant role in treatment algorithms, and adjuvant chemotherapy is gaining more importance; trials are underway in this area. Follow-up should contain biochemical tests as the proposed response definition criteria. We aimed to review the key studies and guidelines in this paper.

In this study, we aimed to compare the engraftment days, graft-versus-host disease (GVHD) development, relapse and overall survival rates in patients using myeloablative/reduced intensity conditioning regimens with posttransplant cyclophosphamide (PTCy) 25 mg/kg x2 with Anti-T lymphocyte Globulin (ATLG) (n = 29) and PTCy 50 mg/kg x2 doses (n = 41) in patients with acute leukemias. Matched related, matched unrelated, 1 mismatched unrelated, and haploidentical donors were selected for the patients. Platelet (median 11 vs 17 days) and neutrophil (median 14 vs 15 days) engraftment times were shorter in ATLG+ PTCy25 treated patients (both p < 0.05); veno-occlusive disease rates, graft failure and poor graft functions were similar between the two approaches (all p > 0.05); cumulative incidences of grade II-IV aGVHD at +100 days, grade III-IV aGVHD at +100 days, and grade II-IV cGVHD at 1-year were comparable between ATLG+PTCy25 and PTCy50 groups (all p > 0.05). Cumulative incidences of relapse and non-relapse mortality at 1-year were similar in two cohorts (both p > 0.05). PTCy50 was associated with a statistically significant benefit in terms of GVHD-free/relapse-free survival (GRFS) at 1-year (p = 0.03). Median GRFS was 115 (95% CI: 42–214) days and 248 (95% CI: 151-not reached) days, respectively [HR was 0.51 (0.28–0.95), p = 0.03; GRFS at 1-year was 20.7% vs 44.3%, respectively]. However, the groups were comparable in terms of PFS and OS. Median PFS was 332 days (95% CI: 182 days-not reached) for ATLG+PTCy25 group. It was not reached (95% CI: 210 days-not reached) for the patients who received PTCy50. Median OS was not reached in either ATLG+PTCy25 (95% CI: 191 days-not reached) or PTCy50 groups (Log rank = 0.42). Our study showed that lowering PTCy dose with ATLG seems to accelerate platelet and neutrophil engraftment rates; confers similar survival and relapse rates, similar acute and chronic GVHD frequency despite increased GRFS at 1-year.

Introduction: Central nervous system (CNS) involvement is reported to represent 5% of extranodal diffuse large B cell lymphoma (DLBCL) at diagnosis. To stratify patients’ risk of CNS involvement, the CNS-International Prognostic Index (CNS-IPI) score was developed. Serum uric acid level has not been incorporated into IPI or CNS-IPI score and its correlation with CNS-IPI risk groups and the CNS relapse has not been studied to date. Therefore, we aimed to retrospectively analyze the relationship between uric acid levels and CNS relapse risk in patients with newly diagnosed adult DLBCL. Methods: Ninety-four adult newly diagnosed DLBCL patients were retrospectively assessed via electronic records and patient files. Demographic data, IPI and CNS-IPI scores, hematologic parameters, serum lactate dehydrogenase, beta-2 microglobulin, serum uric acid and creatinine levels at diagnosis were recorded for analysis. Uric acid levels were compared between CNS-IPI low-intermediate and high groups and cumulative incidence of CNS relapses were analyzed between normal and elevated uric acid levels. Results: Uric acid levels were found to be significantly higher in CNS-IPI high-risk patients (p = 0.008). Elevated serum uric acid levels at diagnosis were significantly associated with high CNS-IPI risk in the logistic regression analysis (OR 1.34, 95% CI 1.05–1.78, p = 0.047). Uric acid also higher than 5.39 mg/dL showed a discriminatory ability in ROC analyses (AUC 0.633, 95% CI 0.495–0.771, p = 0.05). In the competing risks regression analysis, accounting for non-CNS-related death and progression as the competing events, CNS-IPI subgroups and uric acid levels were not significantly associated with the cumulative incidence of CNS relapse (SHR 0.81, 95% CI 0.12–5.59; Fine–Gray, p = 0.834), (SHR 0.55, 95% CI 0.09–3.47; Fine–Gray, p = 0.526), respectively. Conclusions: Even though uric acid levels are significantly higher and showed a discriminatory ability to detect the CNS-IPI high subgroup, elevated uric acid levels could not predict the CNS relapses.

Mesenchymal stem/stromal cells (MSCs) exhibit broad differentiation capability and strong immunoregulatory potential mediated through intercellular communication and the release of diverse paracrine mediators. They represent a promising but still investigational therapeutic approach for managing complications associated with allogeneic hematopoietic stem cell transplantation (allo-HSCT). This review provides an updated synthesis of MSC biology, their bidirectional interaction with immune cells, and their functional contribution to the hematopoietic niche. It also evaluates current clinical evidence regarding the therapeutic roles of MSCs and MSC-derived extracellular vesicles (EVs) in acute and chronic graft-versus-host disease (aGVHD/cGVHD), as well as in poor graft function. Mechanistic insights encompass macrophage polarization toward an anti-inflammatory phenotype, inhibition of dendritic cell maturation, enhancement of regulatory T-cell expansion, and modulation of cytokine signaling pathways. Within the bone marrow milieu, MSCs contribute to stromal restoration and angiogenic repair. Recent phase II/III trials in steroid-refractory (SR)-aGVHD have demonstrated overall response rates ranging from 48 to 71%. Efficacy appears particularly enhanced in pediatric patients and with early MSC administration. Across studies, MSC therapy shows a favorable safety profile; however, heterogeneity in response and inconsistent survival outcomes remain notable limitations. For poor graft function, limited prospective studies indicate hematopoietic recovery following third-party MSC infusions, and combination approaches such as co-administration with thrombopoietin receptor agonists are under investigation. MSC-derived EVs emulate many immunomodulatory effects of their parental cells with a potentially safer profile, though clinical validation remains in its infancy. MSC-oriented interventions hold substantial biological and therapeutic promise, offering a favorable safety margin; however, clinical translation is hindered by product variability, suboptimal engraftment and persistence, and inconsistent efficacy across studies. Future directions should emphasize standardized manufacturing and potency assays, biomarker-driven patient and timing selection, optimized conditioning and dosing strategies, and the systematic appraisal of EV-based or genetically modified MSC products through controlled trials.

Background/Objectives: In multiple myeloma, extramedullary involvement confers poor prognosis. Extramedullary involvement in multiple myeloma may manifest at the time of diagnosis or during a relapse, and it represents a severe condition. Patients with bone involvement are referred to as EM-B, while those with soft tissue involvement are referred to as EM-S. Although various studies have been conducted, the number of studies that categorize extramedullary involvement and examine the effects of flow cytometry, treatment, and genetic findings on prognosis is quite limited. We aimed to contribute to the literature by addressing this gap. Methods: In our study, we retrospectively examined the data of 281 patients followed at our center between 2011 and 2023. Clinical/laboratory data and flow cytometry profiles were collected. Survival was analyzed using Kaplan–Meier and Cox models; logistic regression was used for categorical variables. Hazard ratios (HRs), odds ratios (ORs), and 95% confidence intervals (CIs) were calculated; p-values were reported to three decimals. Results: Extramedullary involvement was absent in 134 (47.7%) patients, while involvement was detected in 147 (52.3%) patients. The median age of the patients was 60 years, and the median follow-up period was 35.4 months. No association was found between CD56 expression on plasma cells, higher Revised Multiple Myeloma International Staging System (R-ISS) score, and extramedullary involvement. Overall survival (OS) was found to be significantly lower in patients with extramedullary involvement. Conclusions: The findings of our study are consistent with many studies in the literature, supporting the finding that survival rates are lower in myeloma patients with extramedullary involvement. Further studies are needed to elucidate the pathogenesis in patients with extramedullary involvement in multiple myeloma and to provide a basis for targeted therapies. Studies involving immunotherapy and cellular therapies may offer a new avenue for these patients.

Large B-cell lymphoma (LBCL) patients who fail frontline therapy (R/R-LBCL) experience highly unfavorable outcomes. The development of T-cell redirecting therapies is rapidly evolving this outlook. However, costs and infrastructural challenges limit access to such innovative therapies. This study was conducted to document the shortcomings of management in the absence of regular access to T-cell redirecting therapies in a contemporary patient population and define subgroups with the most urgent need for accessing innovative treatments. The second-line management and outcomes of a large real-world LBCL cohort from Türkiye were retrospectively analyzed with the participation of nine centers from four different geographical regions. Despite the contemporary period (2012-24), there was no regular access to novel agents. The median PFS-2 was 6.9 months. Less than a quarter of patients (24.3%) received transplantation following a response to second-line therapy, the only subgroup who benefited from the standard care (2-year PFS-2: 67.8%). The remaining 295 patients (75.7% of the cohort) had a median survival of 6.1 months and a 2-year PFS-2 of 10.3%. Progression within a year from diagnosis, non-curative intent at second line, and failure of curative second-line therapy were key adverse features for a dismal prognosis, with median survival durations of 8.8, 2, and 7.4 months, respectively. The current therapeutic strategy of intensive chemoimmunotherapy followed by autologous transplantation yields a reasonable chance of survival for only a fifth of patients. The findings emphasize the urgent need for expanding access to T-cell redirecting approaches in R/R LBCL for early progressors, transplant-ineligible cases, those who fail intensive second-line regimens.