When you have strep throat, lymph nodes in your neck may swell. Women who have breast cancer may get swollen lymph nodes in their armpit.
Bacteria commonly found on the skin can enter your breast Red, swollen, or hot breast tissue; Swollen or painful lymph nodes.
In rare cases, breast cancer or lymphoma may cause swollen lymph nodes in the armpit. Rarely, a person may have a node or group of nodes that grows rapidly.