Does metastatic cancer cause swollen lymph nodes?

Cancer cells can travel from a primary tumour through lymphatic vessels and collect in nearby or more distant lymph nodes. The affected nodes may become enlarged, firm, or uncomfortable. Infection, inflammation, and other conditions can also enlarge lymph nodes, so the finding needs context rather than a conclusion based on touch alone.

The location of the swelling can provide a clue. Nodes near a known tumour may reflect regional spread, while nodes in another drainage area may prompt assessment for a different source. Doctors also consider whether the swelling is on one side or both sides, how it has changed, and whether there are symptoms such as fever, night sweats, unexplained weight loss, pain, or a persistent cough.

A scan can show the size and pattern of lymph nodes, but imaging cannot always distinguish cancer from infection or inflammation. Depending on the situation, a clinician may recommend blood tests, follow-up imaging, or a needle or surgical biopsy. A biopsy examines cells directly and may help identify the cancer type and guide treatment.

Arrange a medical review for a new lump that persists, grows, feels hard or fixed, or appears without an obvious recent infection. If you already have cancer, tell your oncology team about any new swelling, including when it began and whether it is changing.

Do not repeatedly press or massage the area, because this can make it sore and makes change harder to judge. Note its location and any accompanying symptoms. Bring details of recent infections, dental problems, vaccinations, medicines, and previous cancer treatment to the appointment.

Seek urgent medical help if swollen nodes are accompanied by difficulty breathing or swallowing, swelling of the face or neck, severe weakness, confusion, or rapidly worsening symptoms. Contact a clinician promptly for persistent swelling with ongoing fever, drenching night sweats, or unexplained weight loss. These features do not diagnose metastatic cancer, but they should not be ignored.

You could ask: Which lymph-node region is enlarged, and what causes are being considered? Do I need imaging or a biopsy? If I have a known cancer, would testing the node change staging or treatment? What changes should make me contact the team sooner?