Features Partner Sites Information LinkXpress hp
Sign In
Advertise with Us
LGC Clinical Diagnostics

Download Mobile App




New Definition for Plasma Cell Leukemia Proposed

By LabMedica International staff writers
Posted on 09 Jan 2019
Plasma cell leukemia (PCL) is an uncommon but aggressive malignancy that accounts for 1% to 2% of all plasma cell dyscrasias. PCL has been defined as the presence of ≥ 20% circulating plasma cells (CPCs) on conventional white blood cell differential count and an absolute plasma cell count of ≥ 2 × 109/L in the peripheral blood.

This definition includes both primary PCL (pPCL), arising de novo, in the absence of antecedent multiple myeloma (MM), and secondary PCL (sPCL), which describes leukemic transformation of MM. PCL is clinically and biologically distinct from MM with a younger age at diagnosis, higher propensity to show visceral and extramedullary involvement, and unique biologic, immunophenotypic and cytogenetic characteristics.

Hematologists at the Mayo Clinic (Rochester, MN, USA) included in their study 176 patients, for which the median age was 62 years and the majority of which were men (56%). Similar numbers of patients were in each group: 54 patients (31%) had less than 5% CPCs, 63 patients (36%) had between 5% and 19% CPCs, and 59 patients (34%) had 20% or greater CPCs. The percentage of CPCs was derived from the conventional white blood cell differential count, which consists of a microscopic evaluation of Wright-Giemsa-stained peripheral blood smears. Cytogenetic information was collected from patients who underwent fluorescence in-situ hybridization (FISH) evaluation within six months of diagnosis and used to classify these patients as standard risk.

The median overall survival (OS) was 1.4 years for less than 5% CPCs, 1.1 years for between 5% and 19% CPCs, and 1.1 years for 20% or greater CPCs. Due to the similarity in the latter two groups, the study authors re-stratified patients as having either less than 5% or at least 5% CPCs. The median OS for patients with less than 5% CPCs (54 individuals) was 1.4 years and 1.1 years for patients with at least 5% CPCs. To further explore the relationship between CPC count and survival, the study authors compared these 122 patients with 5% or greater CPCs to a cohort of patients who received a diagnosis of multiple myeloma between 1971 and 2016 but did not have detectable CPCs (9,724 individuals).

Patients with 5% or greater CPCs lived a median of three years less than patients with no detectable CPCs (1.1 versus 4.4 years). When the time period of diagnosis was restricted to 2001 or later, the survival difference became even more pronounced. Patients with 5% or greater CPCs lived a median of six years fewer than patients with standard-risk multiple myeloma (1.4 years versus 7.5 years, respectively).

Wilson Gonsalves, MD, an oncologist and a co-author of the study, said, “The current definition of plasma cell leukemia was too restrictive. Many more myeloma patients exist with 5% to 19% circulating plasma cells that behave phenotypically similar to those who have 20% or more circulating plasma cells.” The authors proposed that PCL should be defined as the presence of ≥ 5% CPCs on a conventional peripheral blood smear in patients who meet diagnostic criteria for MM. PCL is a clinically and biologically distinct entity from MM, and specifically high-risk MM, and carries a worse prognosis. The study was published on November 15, 2018, in the Blood Cancer Journal.

Related Links:
Mayo Clinic


Gold Member
Troponin T QC
Troponin T Quality Control
Verification Panels for Assay Development & QC
Seroconversion Panels
New
Fecal DNA Extraction Kit
QIAamp PowerFecal Pro DNA Kit
New
Dermatophytosis Rapid Diagnostic Kit
StrongStep Dermatophytosis Diagnostic Kit
Read the full article by registering today, it's FREE! It's Free!
Register now for FREE to LabMedica.com and get complete access to news and events that shape the world of Clinical Laboratory Medicine.
  • Free digital version edition of LabMedica International sent by email on regular basis
  • Free print version of LabMedica International magazine (available only outside USA and Canada).
  • Free and unlimited access to back issues of LabMedica International in digital format
  • Free LabMedica International Newsletter sent every week containing the latest news
  • Free breaking news sent via email
  • Free access to Events Calendar
  • Free access to LinkXpress new product services
  • REGISTRATION IS FREE AND EASY!
Click here to Register








Channels

Molecular Diagnostics

view channel
Image: Researcher Kanta Horie places a sample in a mass spectrometer that measures protein levels in blood plasma and other fluids (Photo courtesy of WashU Medicine)

Highly Accurate Blood Test Diagnoses Alzheimer’s and Measures Dementia Progression

Several blood tests are currently available to assist doctors in diagnosing Alzheimer's disease in individuals experiencing cognitive symptoms. However, these tests do not provide insights into the clinical... Read more

Immunology

view channel
Image: The findings were based on patients from the ADAURA clinical trial of the targeted therapy osimertinib for patients with NSCLC with EGFR-activated mutations (Photo courtesy of YSM Multimedia Team)

Post-Treatment Blood Test Could Inform Future Cancer Therapy Decisions

In the ongoing advancement of personalized medicine, a new study has provided evidence supporting the use of a tool that detects cancer-derived molecules in the blood of lung cancer patients years after... Read more

Microbiology

view channel
Image: Schematic representation illustrating the key findings of the study (Photo courtesy of UNIST)

Breakthrough Diagnostic Technology Identifies Bacterial Infections with Almost 100% Accuracy within Three Hours

Rapid and precise identification of pathogenic microbes in patient samples is essential for the effective treatment of acute infectious diseases, such as sepsis. The fluorescence in situ hybridization... Read more
Copyright © 2000-2025 Globetech Media. All rights reserved.