There are more than 60 recognized types of non-Hodgkin lymphoma (NHL), according to the World Health Organization classification system. These types are distinguished by which immune cell they start in, how the cells look under a microscope, and how quickly they grow. Most fall into two broad categories based on their cell of origin: B-cell lymphomas, which account for roughly 85% of cases, and T-cell or NK-cell lymphomas, which make up the remaining 15%.
B-Cell Lymphomas: The Most Common Group
The majority of people diagnosed with NHL have a B-cell lymphoma. Within this group, two subtypes dominate. Diffuse large B-cell lymphoma (DLBCL) is the single most common type, with a rate of 5.6 new cases per 100,000 people per year in the United States. It’s typically aggressive, meaning it grows quickly and needs treatment right away. The median age at diagnosis is 67, and the overall five-year survival rate is about 65%, though that climbs to nearly 80% when it’s caught at an early stage.
Follicular lymphoma is the second most common type, accounting for about 20% of all lymphomas. Unlike DLBCL, it’s usually indolent, meaning it grows slowly. Follicular lymphoma is graded on a scale from 1 to 3 based on how the cells look under a microscope. Grades 1 and 2 behave more slowly, while grade 3 (particularly 3B) can act more like an aggressive lymphoma. Some people with low-grade follicular lymphoma don’t need treatment right away and are instead monitored closely over time.
Beyond these two, other notable B-cell subtypes include:
- Mantle cell lymphoma: About 4,000 new cases per year in the U.S., roughly 5% of all NHL. It doesn’t fit neatly into the indolent or aggressive category and often requires a different treatment approach.
- Marginal zone lymphoma: A slow-growing type that can develop in the stomach, spleen, or other organs. It’s sometimes linked to chronic infections or autoimmune conditions.
- Burkitt lymphoma: A very fast-growing lymphoma that comes in three clinical variants. The endemic form, common in Africa, is associated with Epstein-Barr virus in nearly 100% of cases. The sporadic form, more common in Western countries, is linked to the virus in 25% to 40% of cases. A third variant occurs in people with HIV.
- Primary mediastinal B-cell lymphoma: An aggressive type that typically appears as a large mass in the chest, most often in young adults.
T-Cell and NK-Cell Lymphomas
T-cell and NK-cell lymphomas are far less common than B-cell types, but they include a wide range of subtypes, many of them aggressive. The WHO classification lists more than a dozen distinct entities in this group. Some of the more recognized ones include peripheral T-cell lymphoma (not otherwise specified), which is essentially a catch-all for T-cell lymphomas that don’t match a more specific diagnosis, and anaplastic large cell lymphoma, which has both a systemic form and a form limited to the skin.
Mycosis fungoides is a T-cell lymphoma that starts in the skin and typically progresses very slowly, sometimes over years or decades. It can advance into a more aggressive form called Sézary syndrome, where abnormal cells circulate in the blood. Other T-cell types are tied to specific triggers or locations in the body: adult T-cell lymphoma is caused by a virus called HTLV-1, enteropathy-associated T-cell lymphoma develops in the intestines (often in people with celiac disease), and extranodal NK/T-cell lymphoma most commonly affects the nasal area.
Indolent vs. Aggressive Behavior
Regardless of the specific subtype, NHL is also classified by how fast it grows. Indolent lymphomas grow slowly, sometimes so slowly that doctors recommend a “watch and wait” approach rather than immediate treatment. Follicular lymphoma is the most common indolent type. Aggressive lymphomas like DLBCL and Burkitt lymphoma grow quickly and typically require prompt treatment, but they also tend to respond well to therapy because fast-dividing cells are more vulnerable to it.
Some types blur the line. Mantle cell lymphoma, for example, can behave indolently in some patients and aggressively in others. This is one reason the subtype matters so much: two people with “non-Hodgkin lymphoma” can have very different diseases with very different outlooks and treatment timelines.
How Types Differ in Children
NHL in children looks quite different from NHL in adults. Nearly all childhood NHL is high-grade (aggressive), while adults more commonly develop low- or intermediate-grade forms. The three most common categories in children are Burkitt lymphoma, DLBCL, and lymphoblastic lymphoma, along with anaplastic large cell lymphoma. Indolent types like follicular lymphoma and marginal zone lymphoma are rare enough in children that the WHO has designated pediatric versions of these as separate entities from the adult forms, because they behave differently.
Why the Subtype Matters
With more than 60 types, the specific subtype of NHL shapes nearly every aspect of care: whether treatment starts immediately or is delayed, which combination of therapies works best, and what the long-term outlook is. A five-year survival rate can range from above 90% for some indolent B-cell lymphomas to well under 50% for certain aggressive T-cell types. When 40% of DLBCL cases are already at stage IV by the time they’re found, yet the overall five-year survival still reaches 65%, it reflects how responsive many of these cancers are to modern treatment. The sheer number of subtypes is the reason pathologists rely on detailed molecular and genetic testing at diagnosis, not just a biopsy appearance, to pin down exactly which lymphoma someone has.