At medium power, one sees a monotonous proliferation of small cells.
Larger forms are rare or absent.
The lymphoid nuclei are irregular. In fact here the degree of indentation approaches what is seen in a different type of cell, the small-cleaved cell. In the center is a histiocyte with eosinophilic, granular cytoplasm, which is characteristic of many cases of mantle cell lymphoma. Multiple lymphomatous polyposis in the colon.