The World Health Organization (WHO) classifies Hodgkin lymphoma (HL) into 5 subtypes based on the types and arrangements of malignant and non-malignant cells and other characteristics. Four types are referred to as classic HL. The fifth type, nodular lymphocyte predominant HL, is classified separately because it has unique characteristics.
Classic Hodgkin lymphoma
Classic HL accounts for about 95% of all HL cases. The 4 subtypes all have the classic Hodgkin and Reed-Sternberg cells (HRS cells).
Nodular sclerosis HL
Nodular sclerosis HL is the most common type of HL and accounts for about 60% to 80% of cases.
- usually starts in lymph nodes in the neck or chest
- contains the following in the biopsied lymph node:
- nodulesnodulesA small lump or growth made up of cells or tissues. of normal lymphocytes and other immune cells together with HRS cells
- broad bands of fibrosis (scar-like tissue) dividing the lymph node into nodules
- thickening of the lymph node capsule due to the fibrosis
- often found as limited disease involving the lymph nodes in the lower neck, above the collarbone and within the chest
- occurs mainly in younger people and is unusual over age 50
- occurs equally in men and women
Mixed cellularity HL
Mixed cellularity HL is the second most common type of HL and accounts for about 15% to 30% of cases.
- can start in any lymph node but most often occurs in the upper half of the body
- includes many different kinds of cells in the biopsy sample, including HRS cells, inflammatory cells and normal immune cells
- is often advanced at the time of diagnosis
- commonly affects the abdominal lymph nodes and spleen
- commonly has systemic symptoms (B symptoms)
- diagnosed at an average age of 37 years
- is the type of HL most often seen in people with HIV infection
Lymphocyte-rich classical HL
Lymphocyte-rich classical HL accounts for about 5% of cases.
- rarely found in more than a few lymph nodes
- looks a lot like mixed cellularity HL except that most of the cells the biopsy sample are small lymphocytes
- often diagnosed at an early stage in older people, usually men
Lymphocyte-depleted HL is the least common form of HL and accounts for about 1% of cases.
- likely to be advanced when first found, with affected lymph nodes in the abdomen as well the spleen, liver and bone marrow
- includes a few normal lymphocytes or other immune system cells and many HRS cells in the biopsy sample
- seen most often in older people, usually men
- may be seen in people with HIV infection
Nodular lymphocyte predominant Hodgkin lymphoma
Nodular lymphocyte predominant HL (NLPHL) accounts for about 5% of all HL cases. Classic HRS cells are either rare or absent in NLPHL. The abnormal cells are a variation of the HRS cell and are called L&H (lymphocytic and histiocytic) cells or popcorn cells because of their popcorn-like appearance.
- nodular pattern of cells seen in the biopsy sample
- usually diagnosed at an early stage
- most often seen in young men who have no symptoms other than enlarged lymph nodes in the neck or groin