Marginal zone lymphoma (MZL)
Marginal zone lymphoma (MZL) is a group of cancers of the B lymphocytes (B cells). MZL is an indolent (slow-growing) cancer (also known as low-grade). MZL is thought to originate from B cells present in the marginal zone of lymphoid follicles. These can be found in the spleen, lymph nodes and lymphoid tissues. The average age at diagnosis is 60 years, and it is slightly more common in women than men.
There are three main subtypes of MZL:
| MZL Subtype | Description |
| Extranodal marginal zone lymphoma (EMZL) or mucosa-associated lymphoid tissue (MALT) lymphoma | Most common form of MZL. It occurs outside the lymph nodes in places such as the stomach, small intestine, salivary gland, thyroid, eyes, and lungs. MALT lymphoma is divided into two categories: gastric, which develops in the stomach, and non-gastric, which develops outside of the stomach. Many patients with MALT have a previous medical history of chronic infection, inflammation, or autoimmune disorders at the affected organ. |
| Nodal marginal zone lymphoma (NMZL) | NMZL occurs within the lymph nodes and is often referred to as ‘monocytoid B-cell lymphoma’. NMZL is usually slow-growing, but it does have the ability to transform into a more aggressive type of lymphoma. |
| Splenic marginal zone lymphoma (SMZL) | SMZL usually occurs in the spleen and in the blood. It can affect the internal lymph nodes next to the spleen and it can affect the liver. SMZL has been associated with hepatitis C virus infection. |