An immunohistochemical study of diffuse large B-cell lymphoma with molecular subtyping based on Hans algorithm.

Area of Science:

• Hematology
• Oncology
• Immunohistochemistry

Background:

• Diffuse large B-cell lymphoma (DLBCL) is the most common non-Hodgkin lymphoma, representing approximately 40% of all lymphoma cases.
• The International Prognostic Index (IPI) is a standard tool for assessing prognosis in DLBCL based on clinical and laboratory factors.
• Biological subclassification of DLBCL into germinal center B-cell-like (GCB) and non-GCB subtypes using immunohistochemistry (IHC) offers potential prognostic insights.

Purpose of the Study:

• To determine the immunohistochemical profile of DLBCL cases.
• To classify DLBCL patients into GCB and non-GCB subtypes using the Hans algorithm.
• To correlate these subtypes with clinical presentation, Ann Arbor stage, and International Prognostic Index (IPI) scores.

Main Methods:

• A retrospective analysis of 152 DLBCL cases diagnosed between January 2010 and March 2018.
• Immunohistochemistry was performed using CD10, BCL6, and MUM1 markers to apply the Hans algorithm for subtyping.
• Clinical data, including demographics, site of involvement, IPI scores, and Ann Arbor stage, were reviewed.

Main Results:

• The median age of patients was 53 years, with a 2:1 male-to-female ratio.
• Nodal involvement was most common (56.6%), particularly cervical lymph nodes (46.5%). The majority presented at Ann Arbor stage 1 (44.8%).
• The GCB subtype (51.5%) was more frequent than the non-GCB subtype (48.5%). GCB subtype showed a significant association with male sex, while non-GCB subtype was more common in females. No significant correlations were found with other clinical features or prognostic parameters.

Conclusions:

• Immunohistochemistry, utilizing the Hans algorithm, is a valuable and practical method for subtyping DLBCL into GCB and non-GCB categories.
• This subclassification can be readily integrated into routine clinical practice.
• The study highlights a significant association between DLBCL subtypes and sex, suggesting potential biological differences.