The short answer
Lymph nodes are small immune-system structures found throughout the body. A scan may call a node enlarged because it is bigger than expected in that location. Enlarged lymph nodes can happen with infection, inflammation, immune conditions, lymphoma, or cancer spread, so radiologists interpret size with shape, location, pattern, PET uptake, and history.
Lymph nodes are part of the immune system.
Enlarged means bigger than expected, not automatically cancer.
Location, size, shape, number of nodes, and prior scans matter.
Ask whether follow-up imaging, PET, biopsy, or observation is recommended.
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The full explanation.
The short answer
An enlarged lymph node means a lymph node is bigger than expected for its location. Lymph nodes are part of the immune system and filter lymph fluid. Bigger does not automatically mean cancer.
Why nodes enlarge
Lymph nodes can enlarge because of infection, inflammation, immune activity, lymphoma, or cancer cells spreading through the lymph system. Recent vaccines, dental infections, skin infections, and inflammatory conditions can also affect nearby nodes.
What radiologists look at
Size is only one clue. Shape, fatty hilum, border, location, number of nodes, PET uptake, and whether the node is growing or shrinking over time all matter. A small but abnormal-looking node can sometimes matter more than a larger reactive node.
What follow-up can look like
Depending on your cancer history and the report, follow-up may be observation, repeat imaging, ultrasound, PET, or biopsy. Sometimes a node is watched because the most likely explanation is benign.
What to ask next
Ask whether the node is suspicious, indeterminate, or likely reactive, whether older scans were compared, and what result would change the plan. If biopsy is discussed, ask which node is safest and most useful to sample.
Words to know
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Common questions
Does enlarged lymph node mean cancer spread?
Not always. Enlarged nodes can happen for many reasons, including infection and inflammation. Your team interprets the finding in context.
Can PET uptake help?
Sometimes. PET uptake can add information, but inflammation and infection can also show uptake, so it still needs context.
Questions to ask your doctor
Being prepared helps you get the most out of your appointments. Save or print these questions.
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Your next step
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