How does lymphoma develop?

In lymphoma, blood cells called lymphocytes become abnormal. Over time there are enough lymphoma cells to form a lump.


Lymphoma is a cancer of the lymphatic system.

Cancer starts in the cells of our body. Cells are the tiny building blocks that make up the body’s organs and tissues. Cells receive signals from the body, telling them when to grow and when to divide to make new cells. This is how our bodies grow and repair.

Sometimes the process of cell division can get out of control. Too many cells may be made and a cancer, such as lymphoma, can develop.

In lymphoma, blood cells called lymphocytes become abnormal. These are the lymphoma cells. Usually, the body’s immune system destroys abnormal cells. But lymphoma cells are often able to avoid the immune system. This means they can keep dividing and grow out of control.

Over time, there are enough lymphoma cells to form a lump. The most common place for this to happen is in the lymph nodes. But lymphoma can start growing in other parts of the body. Lymphoma that grows outside the lymph nodes is called extra-nodal lymphoma.

Lymphocytes travel around the body. This means that lymphoma can travel from where it first started. It can travel through the lymphatic system from lymph nodes in one part of the body to lymph nodes in another part of the body.

Lymphoma cells can also travel in the bloodstream to organs such as the bone marrow, liver or lungs. The cells may then divide to form a new area of lymphoma.