The disease might then move down lymphatic ducts to nodes in the armpit on the same side of the neck.

CNN: What is Hodgkin lymphoma's effect on the lymphatic system?

There are filters at certain points throughout the lymphatic system called lymph nodes, which usually exist in grape-like clusters.

CNN: What is Hodgkin lymphoma's effect on the lymphatic system?

If you had lymph nodes removed during the mastectomy, the lymphatic channels that drain fluid from your arm to the rest of your body may have been disrupted.

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The cancer eventually moves down lymphatic ducts to other areas of the body to other lymph nodes.

CNN: What is Hodgkin lymphoma's effect on the lymphatic system?

Lymphedema is more common after surgeries that remove most or all of the lymph nodes in the under arm area because there are few if any lymphatic drains left intact after such surgeries, she says.

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