Keypoints

Indolent versus aggressive non-Hodgkin's lymphoma

The classification of non-Hodgkin's lymphoma is based on a number of criteria. A simplified, but valid, way of looking at this is to have two main classifications, or gradings, of non-Hodgkin's lymphoma, which help doctors to decide what treatment to give patients:

• Indolent (also called low-grade or slow-growing)
• Aggressive (also called high-grade or fast-growing)

Indolent non-Hodgkin's lymphomas grow slowly. They often cause no symptoms at first, and so often go undetected for some time. Even after diagnosis, many do not need immediate treatment, sometimes for months or years. Treatment, when needed, is usually effective at making them shrink and even disappear, giving a disease-free period, or 'remission', to the patient. However, they often relapse, or 'recur', and more treatment will then be needed.

The table shows the main differences between indolent and aggressive non-Hodgkin's lymphoma

Aggressive non-Hodgkin's lymphomas grow more quickly. They are more likely to cause symptoms than indolent non-Hodgkin's lymphomas, and they usually need treatment straight away. Although the name 'aggressive' sounds very frightening, these lymphomas often respond very well to treatment. They are, in fact, more likely to be completely cured than indolent non-Hodgkin's lymphomas.

Indolent and aggressive non-Hodgkin's lymphomas can be distinguished by their appearance under a microscope. For this purpose, a sample of the lymphoma tissue needs to be collected in all patients. Most patients will have a biopsy in which an affected lymph node, or part of it, is removed surgically. In others, the diagnosis may have been established 'by accident' during a routine procedure such as a gastroscopy.

It is important to determine the classification of a non-Hodgkin's lymphoma, as the treatments for the two classes can be very different.