B-cell prolymphocytic leukemia has 3 subsets

Understanding splenic B-cell lymphoma/leukaemia with prominent nucleoli: Diagnosis, underpinnings for disease classification and future directions

The 5th edition of the WHO classification of haematolymphoid tumours (WHO-HAEM5) introduced a new category, splenic B-cell lymphoma/leukaemia with prominent nucleoli (SBLPN). The diagnostic entity B-cell prolymphocytic leukaemia (B-PLL) has been discontinued and the category of hairy cell leukaemia variant (HCLv) has been conceptually reframed. B-PLL and HCLv diagnoses were uncommon. Overlap existed between B-PLL and other indolent lymphomas like chronic lymphocytic leukaemia/small lymphocytic lymphoma (CLL/SLL). HCLv lacked consistent cytomorphological, immunophenotypic and genetic features. To address these issues, the WHO-HAEM5 classification has introduced SBLPN to serve as a temporary holding ground for entities that do not neatly fit into the existing classification. Cases previously classified as CD5-negative B-PLL and HCLv fall under the SBLPN category. Some splenic marginal zone lymphoma and splenic diffuse red pulp small B-cell lymphoma cases with higher number of medium or large nucleolated B cells would also be classified as SBLPN under the WHO-HAEM5. This review explores the rationale for discontinuing B-PLL and HCLv diagnoses. It then examines the concept of SBLPN, offers practical guidance for diagnosis and discusses future directions in classifying splenic B-cell lymphomas.

A new case of trisomy 5 with complex karyotype abnormalities in B-cell prolymphocytic leukemia: a case study

Background

The B-cell prolymphocytic leukemia (B-PLL) diagnosis is challenging due to the superposition with mature B-cell leukemia and/or lymphoma.

Objective

An insight case study of trisomy 5 with complex karyotype abnormalities in B-cell prolymphocytic leukemia.

Subject and methods

A 72-year-old man was referred to the Hematology Department, Qilu Hospital, Shandong University, because of persistent fever (10 days) and lymphocytosis. A detailed diagnostic methods including complete blood count, bone marrow aspiration, flow cytometry, conventional karyotype analysis, fluorescence in situ hybridization (FISH), quantitative real-time polymerase chain reaction (qRT-PCR), next-generation sequencing technology (NGS) used to detect 41 kinds of mutant genes related to hematological malignancies were conducted and reasonable therapeutic regimens including emergent leukapheresis accompanied by basification of urine and hydrotherapy, followed by a regimen of cyclophosphamide and dexamethasone.

Results

Subject white blood cell count was 143.43 × 109/L, and 56% prolymphocytes. He did not show lymphadenopathy but splenomegaly. Immunophenotyping of prolymphocytes was CD5(+low), CD10(−), CD11c(−), CD19(+), CD20(+), cCD22(+), CD23(−), cCD79a(+), CD79b(+), FMC7(±), CD43(−), CD3(−), CD56(−), CD103(−), HLA-DR(+), and Lambda(+). R-banding and FISH revealed that leukemia cells carried extra chromosome 5. Considering the rare occurrence of trisomy 5 found in prolymphocytic leukemia, especially in Asians, with rapid disease progression. We know that median survival of B-PLL is three years after diagnosis, while survival time of this patient was only 1 month.

Conclusion

This study could provide the firsthand materials for precision, medicine and mechanism research in cytogenetics and molecular biology. It inferred that trisomy 5 might be a poor prognosis indicator, providing directions for clinical practice in the foreseeable future.