Diffuse large B-cell lymphoma (DLBCL) is a type of aggressive non-Hodgkin lymphoma that originates from B-cells in the lymphatic system. It is the most common subtype of non-Hodgkin lymphoma, accounting for about 30% of all cases. DLBCL is characterized by rapidly growing tumors that can arise in various parts of the body, including lymph nodes, bone marrow, and organs like the spleen or liver. DLBCL can present with a range of symptoms, such as enlarged lymph nodes, fever, night sweats, weight loss, and fatigue. Diagnosis is typically made through a combination of imaging studies, blood tests, and biopsy of the affected tissue. Treatment options for DLBCL may include chemotherapy, radiation therapy, targeted therapy, and stem cell transplantation, depending on the stage and aggressiveness of the disease. Research in the field of DLBCL focuses on understanding the underlying molecular and genetic mechanisms that drive the development and progression of the disease, as well as identifying potential new treatment targets and biomarkers for personalized therapy. Recent advances in immunotherapy, such as chimeric antigen receptor (CAR) T-cell therapy, have shown promising results in treating DLBCL patients who have not responded to standard treatments. Overall, ongoing research efforts are aimed at improving outcomes and quality of life for individuals with DLBCL.