(anaplastic large cell), Stomach
A. Brief Descriptions：
Definition: Anaplastic large cell lymphoma is a T-cell lymphoma consisiting of lymphoid cells that are usually large with abundant cytoplasm and pleomorphic, often horseshoe-shaped nuclei.
The tumor cells are positive for CD30 and EMA on the cell membrane and in the Golgi region.
Moderately aggressive tumor.
B. Gross Findings：
C. Micro Findings：
Gastric mucosa and submucosa are diffusely infiltrated by lymphoma cells.
Pleomorphic large lymphoma cells:
Great variability in nuclear appearance, including some that are horseshoe- or kidney-shaped (hallmark cells) or are multinucleated resembling RS cells.
Dispersed chromatin, multiple prominent nucleoli, abundant cytoplasm.
Atypical mitotic figures are numerous.
Robbins Pathologic Basis of Disease, 6th ed. P.802.
【 Fig. 106-1 (LP)】The gastric mucosa and submucosa are diffusely infiltrated by lymphma cells.
【 Fig. 106-2 (LP)】Gastric glands are surrounded and destroyed by lymphoma cells.
【 Fig. 106-3 (HP)】The nuclei show great variability and have dispersed chromatin and prominent nucleoli.Some multinucleated tumor giant cells are found.
【 Fig. 106-4 (HP)】Kidney or horseshoe-shaped nuclei. Some multinucleated tumor cells with distinct nucleoli are resembling RS cells.