Does the amount of swollen lymph nodes matter? if you have many painless lymph nodes in neck, groin, could it be cancer?

Swollen nodes: This cannot be answered over the internet. Self diagnosis could be extremely dangerous to your health. See your medical doctor for a thorough examination.

↓edOdds ImmuneSystem: includes lymph nodes=filters within lymph vessels (which return blood leaking out of capillaries, body wide, back into the blood stream). White blood cells in nodes screen all fluid for possible threats, including virus, bacteria & malignant cells. When specific WBCs detect something they individually respond to, they rapidly divide creating lymph enlargement. many possibilities, infection likely.