Lymphoma

Lymphoma is a cancer that begins in lymphocytes, a type of white blood cell that circulates in the lymphatic system, which includes lymph nodes, spleen, thymus, and bone marrow. It encompasses many different diseases, but is broadly divided into Hodgkin lymphoma (HL) and non-Hodgkin lymphoma (NHL). HL is characterized by the presence of abnormal Reed-Sternberg cells in affected lymph nodes, while NHL refers to a diverse group of lymphoid cancers with variable behavior and treatment needs.

Most lymphomas originate in lymph nodes, but they can form in other organs. NHLs are more common overall and include B-cell and T-cell lymphomas; HL is less common and has distinct pathology and treatment approaches. Subtypes influence prognosis and therapy, with B-cell lymphomas accounting for the majority of NHL cases.

Common symptoms include painless swelling of one or more lymph nodes in the neck, armpit, or groin, persistent fatigue, fever, night sweats, weight loss, or itching. Risk factors include immune suppression (such as HIV infection or prior organ transplantation), certain infections (for example, EBV in some HL and NHL cases), age, and a family history for some forms.

Diagnosis typically involves a physical exam, blood tests, imaging (CT or PET scans), and a biopsy of affected tissue, with histology and immunophenotyping used to classify the lymphoma. Staging follows the Ann Arbor system, ranging from I to IV, with A or B designations for systemic symptoms.

Treatment depends on the type and stage. HL is commonly treated with chemotherapy, often with radiotherapy; ABVD is a standard regimen. NHL treatment varies by subtype and may include chemo-immunotherapy such as R-CHOP, targeted therapies, radiation, or stem cell transplantation. Prognosis varies by subtype and stage; early HL has favorable survival, while NHL outcomes depend on multiple factors. Long-term follow-up is needed to monitor remission and late effects.