Sinusoidal Involvement of Malinant Lymphoma in Lymph Nodes Simulating Metastatic Carcinoma

ABSTRACT

We present a case of this distinctive variety of malignant lymphoma, which was diagnosed in the axillary lymph nodes of a 66-year-old woman. The patient was admitted to the GS department due to palpable mass on the right axillary area for two months. A 2 x 1 cm sized mass was also palpated on the cervical area. The laboratory and radiologic findings were unremarkable. Axillary dissection was done under the impression of metastatic carcinoma from breast. Received lymph nodes were multiple and variable in size, ranging from 0.5 cm to 5.0 cm in diameter. Histologically, the lymph nodes were partly effaced and involved by nodular and diffuse infiltrations of large lymphoid cells in the subcapsular and medullary sinuses. In diffuse areas, typical starry-sky pattern was seen. Immunohistochemically, the tumor cells were negative for broad-spectrum keratin, but positive for leukocyte antigen, ML, and B cell markers, L26, and 4KB5. T cell marker. UCHL1 was negative. On staining with histiocytic marker, Mac387 antibody, the tingible-body macrophages were only positive. Interstitial plasma cells and some of the tumor cells were positive for lambda light chain. Electron microscopic study, which was done on paraffin embedded tissue showed lymphoid-type of nuclei without cellular junction suggestive for carcinoma.