I have read that painless swollen lymph nodes that are non tender are mostly cancerous. Is this true?

Concerning... Painless lymphadenopathy can be caused by many different things. Anytime there is persistent, painless lymphadenopathy it is concerning for malignancy. However, there are some benign things that can also cause it like autoimmune disorders, skin diseases, tattoos, and medication reactions to name a few. Make sure to follow up and find out what is causing this.
Not true. Lymph nodes can become enlarged from infections, inflammation, and many benign conditions. They can also be enlarged (and painless) if involved by cancer. Typically, we don't worry about cancer for lymph nodes that return to normal size after a few days or weeks.

Related Questions

Are painless swollen lymph nodes for 2 years likely yo be cancerous? No other symptoms. No other conditions related.

How big? That is a good long time. In a young woman it could be hodgkin's disease even with minimal symptoms. In an older patient it could be indolent non-hodgkin's lymphoma. This is worst case, but may be deserving of some work-up. Read more...

Can you guys tell me how big are swollen lymph nodes that are cancerous?

Size is Size. Lymphatic system absorbs/carries things too big to go into the arteries/veins like bacteria eaten by white cells and digested food. Lymph nodes "taste" the lymph for anything bad like bacteria/viruses/cancers, etc. When it detects a problem, it alerts the immune system and your body reacts. They enlarge in response to the inflammation they create when they react regardless of the cause. Read more...

Swollen lymph nodes in left groin, tender to touch.

You need to see MD. Swollen tender lymph node is sign of infection or inflammation. In this particular region they drain the genital area and part of the thigh, that means it could be an infection or inflammation in those areas. I would recommend seeing a physician, specially if you have been sexually active or have any genital ulcer/lesion. I hope you will feel better. Read more...

Why do I have tender swollen lymph nodes in my neck since yesterday?

Infection? You probably have some form of upper respiratory tract infection, likely viral. Lymph nodes help fight this and enlarge and are tender in the process. Hope you are better soon. Read more...
Monitoring Centers. Lymphatic system absorbs/carries things too big to go into the arteries/veins like bacteria eaten by white cells and digested food. Lymph nodes "taste" the lymph for anything bad like bacteria, viruses, cancers, etc. When it detects a problem, it alerts the immune system and your body reacts. They enlarge in response to the inflammation they create when they react. They shrink when all is well. Read more...

I've had swollen lymph nodes all my life on my neck. I get sick a lot, and sometimes the lymph nodes feel tender and bigger.

Hematologist. It is not feasible to provide a meaningful opinion without examining you and your symptoms warrant evaluation by a physician. It would be preferable to consult a hematologist for an evaluation. Read more...