Diffuse Large B-cell Lymphoma with Clear Cells Morphology

Abstract

Diffuse large B-cell lymphoma is a rare type of non-Hodgkin lymphoma composed of
diffuse proliferation of large neoplastic B lymphoid cells with a nuclear size equal to or
exceeding the normal macrophage nuclei. It has become clear that diffuse large B-cell
lymphoma is not a uniform category. Several recognizable variants have clinically distinct
features and, frequently, require specific treatment approaches. Recognition of these
variants and utilization of the appropriate treatments will improve the outcome for the
patients. We report a case of a clear cell variant of diffuse large B-cell lymphoma
involving a lymph node in the neck, which was clinically suspected of being metastatic
carcinoma. A 50-year-old Libyan woman from Misurata presented with cervical
lymphadenopathy and rapidly enlarging retrosternal mass which radiologically was 15.0 x
7.0 cm. Core biopsy of the cervical mass was performed at Misurata Cancer Center (MCC).
The biopsy showed a malignant infiltration exhibiting diffuse areas comprising large cells
with slightly irregular nuclei and clear cytoplasm admixed with a few mononuclear cells. In
these areas, there was high mitotic activity, staining for cytokeratins was negative. These
areas had the following phenotypes: cluster designation marker 20 (CD20) positive, CD10
positive, B-cell lymphoma (Bcl)-2 positive, Bcl-6 positive, CD5 negative, CD3 negative,
melanoma marker (S100) negative, cytokeratin-7 negative, and exhibited a high mitotic
index marker (Ki-67= 80%). According to the immunohistochemical (IHC) findings, we
concluded that this patient has a clear cell variant of diffuse large B-cell lymphoma of
germinal cell type. Our patient is undergoing R-CHOP chemotherapy