Diffuse large B cell lymphoma: abdominal involvement

Histologically, what is the hallmark of Hodgkin's Lymphomalymphoma which is not seen in Non Hodgkinnon-Hodgkin's Lymphoma?

Hodgkin's Lymphomalymphoma is characterised by the presence of Reed-Sternberg cells (considered to be a type of B cell).

Large irregular mass in the left upper quadrant measures approx 15cm15 cm in maximal diameter. There is encasement of the GOJ and fundus of the stomach.

Invasion of the spleen with encasement of the splenic hilum. The mass is also inseparable from adjacent diaphragm, with areas of possible invasion (particularly at the dome of the diaphragm). Speckled calcifications are present in the lesion.

Widespread lymphadenopathy. Enlarged lymph nodes are demonstrated around the upper abdominal aorta, coeliac axis and at the porta hepatis.There is extension into the liver around hepatic arteries.

Abnormal appearance of the pancreatic head, neck and tail which is invaded by tumour.

Multiple cysts in both kidneys, measuring up to 9.5 cm at the lower poles.

Biopsy of the nodal mass surrounding the celiac trunk was performed.

HISTOLOGY:

The lymph node core biopsy shows complete architectural effacement. There is a proliferation of atypical lymphoid cells, forming diffuse sheets. No follicular structures are seen. The atypical lymphocytes are large in size. They have enlarged clefted and hyperchromatic nuclei, prominent nucleoli and scanty cytoplasm. The tumour cells are CD20, bcl-2, bcl-6 and MUM1 positive. The Ki-67 index is about 95%. c-Myc immunostain stains about 70% of the cells. They are CD3, CD5, CD10 and EBER-CISH negative. The features are those of diffuse large B-cell lymphoma, with activated B-cell-like phenotype. Presence of bcl-2 and about 70% of the cells being c-Myc immunostain positive is suggestive of 'double hit' lymphoma.

DIAGNOSIS:  Diffuse large B-cell lymphoma.