NCCN Guidelines for Patients® | Diffuse Large B-cell Lymphoma
13 NCCN Guidelines for Patients ® : Diffuse Large B-cell Lymphoma, 2017 1 DLBCL basics Review Flow cytometry may be done in addition to an IHC panel. If done, it should test for CD45, CD3, CD5, CD10, CD19, CD20, and kappa and lambda light chain proteins. Genetic tests Genetic testing is advised if the IHC test finds GCB-like DLBCL with 1) MYC, and 2) BCL2 or BCL6. Genetic testing will be used to assess for MYC , BCL2, and BCL6 gene rearrangements. A gene rearrangement is the fusion of one gene with another gene to create a new gene. Tests that detect gene rearrangements are a karyotype and FISH ( f luorescence i n s itu h ybridization). DLBCL that has a MYC rearrangement and either a BCL2 or BCL6 rearrangement is called a “double-hit” lymphoma. If all three rearrangements are present, the cancer is a “triple-hit” lymphoma. These DLBCLs grow faster than others. Double-hit lymphomas occur between 2 and 11 out of every 100 people with DLBCL (ie, 2%–11%). Pathology report All lab results are recorded in a pathology report. A report will be written each time tissue is removed from your body and tested. These reports are vital to diagnosis and planning treatment. Review your pathology report(s) with your doctor. Ask questions if you don’t understand. This information can be complex. It’s also a good idea to get a copy of your pathology report(s) and take notes. Review The lymphatic system consists of lymph and a network of vessels and organs. It helps kill germs in the body and transports fluids to the bloodstream. Lymphomas are cancers that start in lymphocytes within the lymphatic system. DLBCL is a lymphoma of B-cells that are within or have been released by germinal centers of lymphatic organs. DLBCL is a fast-growing cancer. It will spread from one group of lymph tissue to the next and to sites outside the lymphatic system. Incisional or excisional biopsy is needed to diagnose DLBCL. The biopsy tissue should be tested by a hematopathologist. The hematopathologist will perform a number of tests that assess for cell type, surface proteins, and maybe genetics.