B-prolymphocytic leukemia: Is it time to retire this entity?

Area of Science:

• Hematology
• Oncology
• Pathology

Background:

• B-prolymphocytic leukemia (B-PLL) is classified as a distinct entity in WHO hematolymphoid neoplasms.
• Diagnostic challenges and significant biologic heterogeneity have been noted in B-PLL.
• Recent studies on limited cohorts hinder robust conclusions regarding B-PLL.

Purpose of the Study:

• To provide a historical review of B-PLL.
• To describe diagnostic and clinical challenges in B-PLL diagnosis.
• To re-evaluate B-PLL as a unique biologic entity.

Main Methods:

• Literature review and analysis of existing data on B-PLL.
• Comparison of B-PLL cases with other small B-cell lymphomas.
• Assessment of biologic and molecular heterogeneity.

Main Results:

• B-PLL diagnosis presents considerable challenges.
• Substantial biologic and molecular heterogeneity exists within B-PLL.
• Many B-PLL cases share similarities with other small B-cell lymphomas and can arise from their transformation.

Conclusions:

• The frequency of B-PLL has significantly decreased, indicating its rarity.
• Cases classified as B-PLL are likely not a unique biologic entity.
• B-PLL may represent a shared state of morphologic transformation in various small B-cell lymphomas.