New prognostic relevant factors in primary cutaneous diffuse large B-cell lymphomas

Area of Science:

• Hematology
• Oncology
• Dermatopathology

Background:

• Primary cutaneous diffuse large B-cell lymphoma (PCDLBCL) understanding has advanced through gene profiling.
• Gene profiling reveals an activated proliferation profile in leg-type PCDLBCL, with proto-oncogene and transcription factor overexpression.
• Gene profiling is impractical for routine PCDLBCL diagnostics.

Purpose of the Study:

• To establish a practical immunohistochemical staining panel for prognostication of PCDLBCL.
• To correlate immunohistochemical findings with clinical data for risk stratification.

Main Methods:

• Analysis of 35 PCDLBCL patients (14 follicle center, 21 leg type).
• Immunohistochemical staining for CD5, CD138, BCL2, BCL6, OCT2, MUM1, FOXP1, and cMYC.
• Correlation of staining patterns and clinical data with patient prognosis.

Main Results:

• All cases were negative for CD5 and CD138.
• Distinct staining patterns for BCL6, BCL2, OCT2, MUM1, and FOXP1 differentiated PCDLBCL subtypes.
• BCL2, OCT2, and/or MUM1 expression indicated poor prognosis; BCL6 expression suggested a favorable prognosis.
• cMYC expression was not prognostic.
• Ulceration, leg manifestation, or multiple lesions correlated with worse prognosis.

Conclusions:

• Immunohistochemical markers BCL2, BCL6, MUM1, and OCT2 aid in prognostication of PCDLBCL.
• Clinical presentation evaluation is crucial for identifying risk factors in PCDLBCL.
• Findings support the WHO/EORTC classification of PCDLBCL.