Hodgkin lymphoma is a cancer of the B lymphocytes (B cells), which is marked by the presence of very large cells called Reed-Sternberg (RS) cells. HL usually starts in the lymph nodes but can also spread to other organs. It occurs both in children and adults; however, it is most commonly diagnosed in young adults (ages 15-35) and in older adults (age 50 and older).
HL can be classified into either nodular lymphocyte predominant Hodgkin lymphoma (NLPHL) or classical Hodgkin lymphoma (CHL):
- Nodular lymphocyte predominant Hodgkin lymphoma (NLPHL): The cancer cells in NLPHL are variants of RS cells called LP cells (for ‘lymphocyte-predominant’) or popcorn cells (because they look like pieces of popcorn). Most patients present with enlarged lymph nodes in the neck or armpit regions. It tends to grow at a slower rate than CHL and be diagnosed at an earlier stage. It can occur at any age and is much more common in men than in women. Treatment is usually successful; however, relapses are common, sometimes many years after the initial diagnosis.
- Classical Hodgkin lymphoma (CHL): CHL accounts for 90-95% of all HL diagnoses. The most common sites for CHL are in the neck, under the arms and in the chest. CHL will typically start in the lymph nodes and often spreads through the lymph vessels from one lymph node to the next in a predictable order. CHL may also spread to other areas and organs outside of the lymphatic system. CHL can be further subdivided into four main subtypes:
CHL can be further subdivided into four main subtypes below.
Classical Hodgkin lymphoma (CHL) Subtypes
- Most common subtype, accounting for 60-80% of CHL.
- Most common in adolescents and adults under age 50, but it can occur in people of any age.
- More common in women than men.
- Tends to start in lymph nodes in the neck or chest.
- The involved lymph nodes contain HRS cells mixed with normal white blood cells. The lymph nodes often contain a lot of scar tissue, which is where the name nodular sclerosis (scarring) originates.
- Most patients are cured with current treatments.
- Accounts for less than 5% of CHL.
- It usually occurs in the upper half of the body and is rarely found in more than a few lymph nodes.
- The cancer may be diffuse (spread out) or nodular in form and is characterized by the presence of numerous normal appearing lymphocytes and classic HRS cells.
- Lymphocyte-rich CHL has some features that are intermediate between other CHL and NLPHL.
- This subtype of HL is usually diagnosed at an early stage in adults and has a low relapse rate.
- Accounts for about 15-30% of CHL.
- Primarily affects older adults.
- More common in men than in women.
- It can start in any lymph node but most often occurs in the upper half of the body.
- The lymph nodes contain many HRS cells in addition to several other cell types.
- More advanced disease is usually present by the time this subtype is diagnosed.
- Very rare; diagnosed in less than 1% of CHL.
- It is seen mainly in older people.
- More likely to be found in lymph nodes in the abdomen as well as in the spleen, liver, and bone marrow.
- Abundant HRS cells and few normal lymphocytes are present in the lymph nodes.
- Usually not diagnosed until it is widespread throughout the body.
- Aggressive disease.