Types and Features of Classical Hodgkin Lymphoma

Classical Hodgkin lymphoma is an older term used to describe a group of four common types of Hodgkin disease. Together they comprise more than 95% of all Hodgkin disease in developed countries.

Subtypes

There are four main subtypes of Hodgkin lymphoma:

• Nodular Sclerosing Hodgkin Lymphoma (NSHL): This is the most common variety of Hodgkin lymphoma. It occurs more in younger people.
• Mixed Cellularity Hodgkin Lymphoma (MCHL): This is the second most common and it is a type that may occur at any age.
• Lymphocyte Rich Classical Hodgkin Lymphoma (LRCHL): This is an uncommon type and it is more common in middle-aged individuals.​
• Lymphocyte Depleted Hodgkin Lymphoma (LDHL): This is the least common variety of classic Hodgkin lymphoma and it is more common in older individuals and those with impaired body defenses. While the other types mostly occur in lymph nodes in the upper half of the body, in LDHL they are affected in the abdomen and there can be involvement of the spleen, liver and bone marrow.

What Distinguishes Classical Hodgkin Disease

In all of the subtypes of classic Hodgkin lymphoma, the cancer cells are an abnormal type of B lymphocyte called Reed-Sternberg (RS) cells. They have a typical appearance that is unlike any other cells in the body. When they are seen in a lymph node biopsy, they aid in the diagnosis of Hodgkin disease. They are very large, and the typical RS cell has two mirror-image nuclei giving it an owl eyes appearance. There are variants of this appearance, but they are easily identified by the pathologist. The RS cells are the cancerous cells, but the enlargement of the lymph nodes is due to the reaction of other immune cells in the lymph nodes. The subtypes of classic Hodgkin disease vary in what other cell types are found in the lymph nodes and which nodes are affected.

Symptoms and Diagnosis

The symptoms of lymphoma are not very different between these four types, but the patterns of enlarged lymph nodes and the stage at diagnosis may be quite different. As a result, the outcomes after treatment may also be different. An experienced pathologist can determine the exact type of Hodgkin by examining lymph node biopsy samples under the microscope.

Classic Hodgkin disease is staged by symptoms, the physical exam, the lymph node biopsy, imaging tests, blood tests, and sometimes with bone marrow tests. These are assessed with the Cotswold staging classificaton and assigned to Stages I through IV. They are also assigned A vs. B for being bulky or not, meaning that the tumors in the chest are a third as wide as the chest or 10 centimeters across in other areas.

Treatment

Treatment of classic Hodgkin disease depends on the type, stage and whether it is bulky, plus symptoms, lab results, age, and general health. In general, chemotherapy is given, followed by radiation therapy. If there isn't a response to these treatments, it may be followed by a different chemotherapy regimen, stem cell transplant, or treatment with the monoclonal antibody brentuximab vedotin.