Diagnosis
Microscopic examinations of involved tissues reveal large neoplastic cells that are typically classified as B-cells based on their expression of B-cell marker proteins (e.g. CD20, CD19, CD22, CD79, PAX5, BOB1, OCT2, an immunoglobulin [usually IgM but occasionally IgG or IgA)], CD30, and in ~20–25% of cases PD-L1 or PD-L2 (PD-L1 and PD-L2 are transmembrane proteins that normally function to suppress attack by the immune system). These cells arrange in a diffuse pattern, efface the tissues architecture, and resemble Centroblast cells (80% of cases), Immunoblast cells (8–10% of cases), or anaplastic cells (9% of cases; anaplastic cells have bizarre nuclei and other features that may mimic the Reed–Sternberg cells of Hodgkin disease or the neoplastic cells of anaplastic large cell lymphoma). Rarely, these neoplastic cells are characterized as having signet ring or spindle shaped nuclei, prominent cytoplasmic granules, multiple microvillus projections, or, when viewed by electron microscopy, tight junctions with other cells. These neoplastic tissue infiltrates are often accompanied by small non-malignant T-cell lymphocytes and histiocytes that have a reactive morphology. Variants of DLBCL, NOS
The World Health Organization, 2016, requires that the neoplastic cells in DLBCL, NOS be further defined based on whether they are derived from germinal center B-cells (i.e. GBC) or activated B-cells (i.e. ABC) as identified by gene expression profiling (GEP) or are GBC or non-GBC as identified by immunohistochemical (IHC) analyses. As identified by GEP, which measures all cellular messenger RNAs, GBC and ABC represent about 50 and ~35% of DLBCL, NOS cases, respectively, with ~15% of cases being unclassifiable.
Macrodontia may refer to:

Macrodontia (tooth), a tooth disorder where the teeth are larger than normal
Macrodontia (beetle), a genus of beetles

See also
Macrodonta (disambiguation)