Non-Hodgkin lymphoma (NHL) is a lymphoid malignancy with more than 30 subtypes. The subtypes are categorized based on the lymphocyte type involved – B-cell, T-cell or NK cell (natural killer). The majority of lymphoid malignancies are of B-cell type. NHL begins when a lymphocyte changes into a cancer cell that divides and grows to form more cancer cells. These cancer cells join together to form tumors (lymphomas) in the lymph nodes and elsewhere in the body. These cancerous cells cause the lymph nodes in the neck, armpits, groin to enlarge. The cancerous lymphocytes may also collect in the liver, spleen and bone marrow.
Annually approximately 69,000 people develop NHL in the United States. Although NHL can occur in people of any age, most people diagnosed with NHL are over 60 years of age.
Diffuse large B-cell lymphoma (DLCL) is the most common subtype of NHL. This is an aggressive B-cell lymphoma requiring treatment. Follicular lymphoma (FL) is a more indoent B-cell lymphoma. There are a number of other less common MHL subtypes based on B-cell and T-cell phenotypes. Mantle cell lymphoma presents as disseminated disease predominately in older male patients. The majority of patients with T-cell linage lymphoblastic lymphoma and B-cell lineage Burkitt’s lymphoma comprise children, adolescents and young adults. These are rapidly progressive disorders that require intensive multiagent chemotherapy.
For many patients with NHL, chemotherapy alone may bring long-term remission, but for others with more aggressive disease or with disease that returns after chemotherapy, a blood or marrow transplant may be the best option to achieve long-term remission. There are two types of transplants: autologous and allogeneic. An autologous transplant uses the patient’s own blood forming cells which are collected and stored. An allogeneic transplant uses healthy blood-forming cells from a family member or unrelated donor. Both types of transplants are used for NHL, but autologous is more common.
Whether a transplant is right for a specific patient depends on patient age, overall health, stage of the disease and aggressiveness of the disease. A transplant doctor will weigh the risks of the disease coming back against the risks of a transplant. There are medical guidelines for when someone should be referred for a transplant consultation, whether the patient may or may not benefit from a transplant at that time.