Large cell lymphoma with microvillus-like projections: an ultrastructural study

Area of Science:

• Oncology
• Pathology
• Cell Biology

Background:

• Large cell lymphomas are a heterogeneous group of lymphoid malignancies.
• Accurate diagnosis is crucial for appropriate treatment and patient outcomes.

Observation:

• Electron microscopy of 10 large cell lymphoma cases revealed slender peripheral cytoplasmic projections on tumor cells.
• These projections, when numerous, can be mistaken for microvilli, a feature often associated with adenocarcinoma.

Findings:

• Immunoperoxidase staining identified monoclonal cytoplasmic immunoglobulin in 40% (4/10) of the cases, supporting lymphoid origin.
• Muramidase stains were negative in all cases, ruling out myeloid lineage.
• Nine out of 10 cases were presumed to be of B-cell lineage.

Implications:

• The observed cytoplasmic projections highlight potential diagnostic challenges in differentiating large cell lymphoma from carcinoma.
• Understanding these morphological features aids in accurate pathological diagnosis.
• Comparison with transformed lymphocytes from reactive lymph node follicles provides insights into the cellular origins of these lymphomas.