DLBCL

Diffuse large B-cell lymphoma (DLBCL) is the most common form of non-Hodgkin lymphoma. It is an aggressive malignancy of mature B cells that typically forms rapidly enlarging masses and can involve extranodal sites. DLBCL mainly affects adults, with a median age in the 60s and a slight male predominance. Patients often present with a rapidly growing mass and may have B symptoms such as fever, night sweats, or weight loss.

Pathology and molecular features: Histology shows diffuse sheets of large B cells with vesicular nuclei and prominent nucleoli. Immunophenotype usually includes CD19, CD20, and CD79a. Two major molecular subtypes are germinal center B-cell–like (GCB) and activated B-cell–like (ABC), with ABC associated with worse outcomes. Some tumors harbor MYC, BCL2, or BCL6 rearrangements (double- or triple-hit), linked to higher risk.

Diagnosis and staging: Diagnosis relies on biopsy with immunophenotyping and flow cytometry. PET-CT is used for staging and treatment response. Staging follows the Ann Arbor system, and risk stratification uses the International Prognostic Index (IPI), incorporating age, LDH, performance status, stage, and extranodal sites.

Treatment: First-line therapy is rituximab plus CHOP (R-CHOP) given every 21 days for about six cycles. Early-stage disease may require fewer cycles and localized radiotherapy. For relapsed or refractory DLBCL, options include salvage chemotherapy with autologous stem cell transplantation, and newer approaches such as CAR-T cell therapy or targeted agents, depending on prior treatment and biology.

Prognosis and research: With current therapy, many patients achieve long-term remission, though outcomes vary by stage, age, performance status, and molecular subtype. Five-year survival improves for early-stage disease but remains poorer for high-risk biology. Ongoing research seeks refined molecular classifications and novel therapies to improve outcomes and reduce toxicity.