Hodgkin's lymphoma

Hodgkin's lymphoma
Name	Hodgkin's lymphoma
Synonyms	Hodgkin lymphoma, Hodgkin's disease
Caption	A photomicrograph showing a characteristic Reed–Sternberg cell (center), a hallmark of the disease.
Field	Hematology, Oncology
Symptoms	Painless lymphadenopathy, fever, night sweats, weight loss, pruritus
Complications	Superior vena cava syndrome, Pleural effusion, Spinal cord compression
Onset	Most common in young adults (20s–30s) and older adults (over 55)
Types	Nodular sclerosis, Mixed cellularity, Lymphocyte-rich, Lymphocyte-depleted, Nodular lymphocyte-predominant
Causes	Unknown; associated with Epstein–Barr virus infection, HIV/AIDS, Family history
Risks	Young adult age, Male sex, Family history, Immunosuppression
Diagnosis	Excisional lymph node biopsy, Blood test, Medical imaging (PET-CT, CT scan)
Differential	Non-Hodgkin lymphoma, Infectious mononucleosis, Tuberculosis, Sarcoidosis
Treatment	Chemotherapy (e.g., ABVD, BEACOPP), Radiation therapy, Stem cell transplantation
Medication	Doxorubicin, Bleomycin, Vinblastine, Dacarbazine, Brentuximab vedotin, Nivolumab
Prognosis	Generally high cure rates, especially in early stages
Frequency	~3 per 100,000 per year in the United States

Hodgkin's lymphoma is a malignancy originating from B lymphocytes within the lymphatic system. It is distinguished from other lymphomas by the presence of distinctive giant cells known as Reed–Sternberg cells within affected lymph nodes. The disease typically presents with painless swelling of lymph nodes in the neck and is often highly curable with modern therapeutic regimens, leading to survival rates exceeding 85% for many patients. Its management involves a multidisciplinary approach led by specialists in hematology and radiation oncology.

Signs and symptoms

The most common initial presentation is painless, firm enlargement of lymph nodes, often in the neck, above the collarbone, or in the chest. Systemic "B symptoms" include unexplained fever, drenching night sweats, and significant weight loss, which are important for staging. Other possible symptoms are generalized pruritus and pain in affected nodes following alcohol consumption. Complications from bulky disease can involve the superior vena cava, lungs, or cause spinal cord compression.

Classification and subtypes

The disease is primarily classified according to the World Health Organization system, which divides it into classical forms and the distinct nodular lymphocyte-predominant Hodgkin lymphoma. Classical subtypes include nodular sclerosis, which is common in young adults and often involves the mediastinum, and mixed cellularity, frequently associated with Epstein–Barr virus and seen in older patients or those with HIV/AIDS. The lymphocyte-rich and rare lymphocyte-depleted subtypes complete the classical group, while nodular lymphocyte-predominant Hodgkin lymphoma involves popcorn-shaped L&H cells and behaves more like an indolent B-cell lymphoma.

Causes and risk factors

The exact cause remains unknown, but infection with the Epstein–Barr virus is a significant associated factor, particularly in the mixed cellularity subtype. Other established risk factors include a compromised immune system, such as in patients with HIV/AIDS or those taking immunosuppressive medications after organ transplantation. A modestly increased risk is noted among siblings, suggesting a potential genetic susceptibility, and the disease has a higher incidence in North America and Northern Europe compared to Asia.

Diagnosis and staging

Definitive diagnosis requires an excisional lymph node biopsy to identify characteristic Reed–Sternberg cells within an appropriate cellular background. Immunohistochemistry is used to confirm the phenotype, typically positive for CD15 and CD30. Staging follows the Ann Arbor classification, incorporating findings from physical examination, blood tests (including ESR and LDH), and imaging with PET-CT and CT of the chest, abdomen, and pelvis. A bone marrow biopsy may be performed in advanced cases.

Treatment and prognosis

Treatment is based on the disease stage and risk factors. Early-stage disease is often treated with combined chemotherapy (such as ABVD or Stanford V) and involved-site radiation therapy. Advanced stages are managed with more intensive chemotherapy regimens like BEACOPP. For relapsed or refractory disease, salvage chemotherapy followed by high-dose therapy and autologous stem cell transplantation is standard, with newer agents like brentuximab vedotin and nivolumab showing efficacy. Prognosis is generally excellent, with over 90% of patients with limited-stage disease achieving long-term remission.

Epidemiology and history

The annual incidence in the United States is approximately 3 cases per 100,000 people, with a characteristic bimodal age distribution showing peaks in young adulthood (ages 20–34) and later in life (after age 55). It is slightly more common in males than females. The disease is named after Thomas Hodgkin, who first described it in 1832 while working at Guy's Hospital in London. Major therapeutic advances, including the development of the MOPP chemotherapy regimen by researchers at the National Cancer Institute and the refinement of radiation techniques, have transformed it from a fatal illness to a largely curable one.

Category:Lymphomas Category:Hematology