EJHaem最新文献

Introduction

Polatuzumab vedotin (Pola) is an antibody-drug conjugate approved for the treatment of diffuse large B-cell lymphoma (DLBCL). Several reports suggest that the tumor microenvironment influences the outcome of DLBCL treatments; with Pola, however, the link between tumor microenvironment and treatment outcome remains unclear.

Objectives and Methods

We analyzed the relationship between the antitumor effect of Pola and immune status, focusing on innate immune cells in the tumor microenvironment by utilizing a xenograft mouse model and a syngeneic mouse model.

Results

In the DB (DLBCL cell line) xenograft model, Pola induced infiltration of macrophages and natural killer cells, which contributed to the antitumor effect of Pola. Moreover, Pola induced the release of several damage-associated molecular patterns from DB cells and enhanced the migration of immune cells under ex vivo co-culture conditions. A syngeneic mouse model also confirmed the involvement of innate immune cells in the Pola effect.

Conclusion

This study demonstrates that Pola treatment alters MΦ and NK cell infiltration in tumors, highlighting these innate immune cells' essential contribution to Pola's antitumor activity.

Trial Registration

The authors have confirmed clinical trial registration is not needed for this submission

Background

Immunophenotypically defined mixed-phenotype acute leukemias (MPAL) are rare and remain a diagnostic and therapeutic dilemma. We aim to explore the clinicopathologic characteristics and oncological outcomes of these entities.

Methods

A total of 52 patients with immunophenotypically defined MPAL were identified from our pathology database. Medical records and archived diagnostic pathology data were retrospectively reviewed and analyzed.

Results

This cohort consisted primarily of B/myeloid (80.8%), followed by T/myeloid (11.5%), B/T (5.8%), and B/T/myeloid (1.9%) immunophenotypes. There were 19 adults and 33 pediatric patients, with a male-to-female ratio of 2.1:1. A total of 34 biphenotypic and 18 bilineal MPAL patients were observed. Comparative analyses suggested that acute lymphoblastic leukemia (ALL)-directed chemotherapy, pediatric population, and biphenotypic type significantly correlated with higher complete remission rates (p = 0.007, p < 0.001, and p = 0.021, respectively); however, statistically significant differences were not observed in relapse rates (p = 0.343, p = 0.232, and p = 0.690, respectively). Survival analyses revealed that ALL-directed chemotherapy, pediatric population, and B-MPAL subtype (i.e., B/myeloid, B/T, and B/T/myeloid) correlated with significantly better overall survival (p < 0.001, p < 0.001, and p = 0.006, respectively).

Conclusion

Our findings support that immunophenotypically defined MPALs are distinctive entities with immunophenotypic diversity. Multiple factors, including treatment type, lineage component, and age group, represent strong predictors of clinical outcomes. Future studies focusing on incorporating immunophenotype and molecular profiles may contribute to better classification, prognostication, and treatment establishment.

Trial Registration: The authors have confirmed clinical trial registration is not needed for this submission

Background

Extranodal peripheral T-cell lymphomas (PTCLs) comprise a diverse group of lymphomas whose real-world presentation and course are infrequently studied.

Methods

We retrospectively analyzed the clinical characteristics and survival outcomes of 50 patients at a tertiary cancer center in Singapore between 2002 and 2024.

Results

The cohort comprised 26 males and 24 females, with a median age of 50 years (range 16–84 years). The 5-year progression-free survival (PFS) and overall survival (OS) were 20.2% and 66.6%, respectively. Male sex (p = 0.03) and lack of complete response to initial treatment (p < 0.001) predicted poorer PFS. Age > 60 years (p < 0.001), nodal involvement (p = 0.02), gastrointestinal origin (p < 0.001), > 1 extranodal site of involvement (p = 0.02), and International Prognostic Index score > 2 (p < 0.001) predicted poorer OS. We also studied two subtypes: subcutaneous panniculitis-like T-cell lymphoma (SPTCL) (n = 7) and monomorphic epitheliotropic intestinal T-cell lymphoma (MEITL) (n = 7). Patients with SPTCL had a median age of 29 years and presented with lesions mimicking reactive lymph nodes (43%), lipomas (29%), or erythema nodosum (14%); no mortality was noted in our series. Patients with MEITL had a median age of 68 years and presented with bowel emergencies including perforation (57%), bleeding (14%), and obstruction (14%); all patients progressed or relapsed, and 5 demised—3 with small bowel relapse, 2 with central nervous system relapse.

Conclusion

Our study provides insights into extranodal PTCLs and serves to guide our management of these rare lymphomas.

Trial Registration: The authors have confirmed clinical trial registration is not needed for this submission

Background

Molecular T-cell receptor (TCR) clonality testing cannot link clonality to immunophenotype, limiting discrimination between malignant and clonal reactive T-cell expansions.

Methods

We evaluated TRBC1/TRBC2 immunophenotyping in 50 consecutive cases with suspected T-cell malignancy, assessing restriction (ratio > 10) across T-cell subsets.

Results

TRBC immunophenotyping showed 100% sensitivity for T-cell malignancy if assessed within subsets or phenotypically abnormal populations. Malignant clones predominantly showed CD4αβ/CD8αβ restriction (18/21), while reactive clones predominantly showed γδ/dual-positive/dual-negative restriction (15/16), enabling enhanced discrimination.

Conclusion

TRBC immunophenotyping provides sensitive clonality detection with phenotypic lineage assignment, adding diagnostic clarity beyond molecular testing and supporting integration into routine workflows.

Trial Registration: The authors have confirmed clinical trial registration is not needed for this submission.

Background

Measurable residual disease (MRD) monitoring is a critical component of risk stratification and therapeutic decision-making in B-cell acute lymphoblastic leukemia (B-ALL). Multiparameter flow cytometry (MFC) is widely used, but its sensitivity is limited to 10⁻⁴–10⁻⁵. Next-generation sequencing (NGS) platforms offer greater sensitivity (up to 10⁻⁶) but are often limited by cost, infrastructure requirements, and reliance on FFPE tissue. We evaluated the performance of a commercially available NGS-based assay, the Oncomine B-cell Clonality panel, adapted at our center for MRD monitoring using diverse sample types.

Methods

In this retrospective study, 32 B-ALL patients were analyzed. Diagnostic clonotypes were identified from archival stained bone marrow aspirate smears in all cases, and FFPE bone marrow tissue in five. Longitudinal MRD monitoring was performed on bone marrow aspirates collected in EDTA. Serial dilution experiments (10⁻²–10⁻⁶) were conducted to assess sensitivity; reproducibility was tested in triplicates across runs. MRD results from NGS were compared to MFC, and statistical agreement was evaluated using Spearman's correlation and Cohen's kappa.

Results

Baseline clonotypes were detected in 29/32 patients (90.6%). The assay demonstrated a limit of detection of 10⁻⁶ and high reproducibility (R² = 0.991). NGS and MFC showed 86.5% concordance; NGS detected MRD earlier than MFC in eight cases (44–124 days). Sensitivity and specificity of NGS relative to MFC were 100% and 82.98%, respectively. Clonal detection succeeded in both FFPE and stained slides.

Conclusion

This adapted NGS assay offers a sensitive, reproducible, and sample-flexible MRD monitoring tool for B-ALL, with potential for broader clinical application.

Trial Registration: The authors have confirmed clinical trial registration is not needed for this submission.

Background

Cytomorphological examination and classification of bone marrow (BM) cells using a microscope is essential for diagnosing various diseases affecting the haematopoietic system. However, this requires expertise, is effort-intensive and is inherently subjective.

Methods

We developed a method for automatically capturing BM cell images at the single-cell level using an existing cell image analyser designed for peripheral blood. The captured BM cell images were pre-classified by the same analyser and subsequently viewed on a large screen by cytomorphologists for BM cell classification. The data consistency in BM blast percentages between the digital and conventional optical microscopy (CM) methods was examined.

Results

During the 3.5-year study period, 657 (96.2%) of the 683 aspirated samples underwent BM cell classification using the digital method. Digital cell images were captured at 2000× magnification and stored permanently, which allowed high-quality cell image analysis at any time by anyone. Cell images could be compared side-by-side across different cell classes, which improves the cell-classification accuracy. The detailed cell morphology in some cases differed slightly between the digital images and CM. BM blast percentage was comparable between the developed method and CM when examining patients with myelodysplastic syndromes (MDS) and other conditions that need to be differentiated from MDS. In a multicentre study, cytomorphologists who used this method for the first time could perform cell classification.

Conclusion

This machine-assisted and human-centred approach enhances objectivity in BM cell classification, aligns with the needs of the digital era and facilitates data sharing.

Trial Registration: The authors have confirmed clinical trial registration is not needed for this submission.

Background

Genomic profiling of patients with myeloid neoplasms (MN) may detect variants with high variant allele frequency (VAF), indicating potential germline origin. All current guidelines recommend further investigation of such variants.

Objective

To define the proportion of variants with suspected germline origin that prompted germline investigation in patients evaluated for MN in the clinical setting.

Methods

We included 738 patients investigated for MN in Mid-Sweden between May 2020 and January 2023 with available sequencing data in genes of interest (GOI) according to the Nordic and other international guidelines.

Results

In total, 90 patients (12%) carried pathogenic/likely pathogenic (P/LP) variants in GOI according to the Nordic guidelines, with TP53, RUNX1, and NRAS being the most common (n = 37, n = 27, and n = 9, respectively). The potential germline origin was investigated in 16/90 (18%) patients. Two patients (2/16, 12.5%) with germline variants were identified (DDX41 and RUNX1, n = 1, respectively). In patients treated with allogeneic stem-cells transplantation (n = 15) the investigation rate was higher (7/15, 47%, p < 0.005) compared to the non-transplanted ones. Applying the European Leukemia Net (ELN) guidelines the number of patients with variants in GOI increased up to 177 mainly due to the inclusion of TET2, while application of other international guidelines leads to similar results with the Nordic ones.

Conclusion

We report a low investigation rate for variants of suspected germline origin detected during the genomic profiling of patients investigated for MN in the clinical setting. Our study underscores the need for further awareness regarding germline investigation for hematological malignancies.

Trial Registration: The authors have confirmed clinical trial registration is not needed for this submission.