Swollen lymph nodes in the neck do not necessarily mean cancer, as there are many different causes for this. Swollen lymph nodes can be a response to various factors, including:

1. Infections: This is the most common cause. Bacterial or viral infections, such as a cold, sore throat, or tonsillitis, can cause lymph nodes in the neck to swell.

2. Inflammatory diseases: Autoimmune diseases like lupus or rheumatoid arthritis can also cause swollen lymph nodes.

3. Mononucleosis (mono): Caused by the Epstein-Barr virus, this can lead to swollen lymph nodes in the neck.

4. Medication side effects: Some medications can cause swollen lymph nodes as a side effect.

However, swollen lymph nodes in the neck can also be a sign of cancer, particularly when caused by lymphoma (cancer of the lymphatic system) or metastasis from other cancers (e.g., breast cancer, lung cancer). Cancer-related swollen lymph nodes are often painless, firm, and do not shrink over time.

If the swollen lymph nodes in your neck persist, are painless, or are accompanied by other symptoms such as unexplained weight loss, fever, or night sweats, it is important to consult a doctor for further evaluation and accurate diagnosis.