Radiation therapy uses high-energy radiation to shrink tumors and kill cancer cells (1). X-rays, gamma rays, and charged particles are types of radiation used for cancer treatment.
1 Lymph nodes of the armpit and neck may also be involved. 2  Viral infections such as infectious mononucleosis may affect the whole body and cause generalized lymph node swelling in various parts of the body, such as neck, armpit or groin.
Some medications and allergic reactions to medications can cause the lymph nodes to swell. Antiseizure and antimalarial drugs can also cause lymph nodes to swell. Sexually transmitted infections, such as syphilis or gonorrhea, can cause the lymph nodes in the groin area to swell. Other causes of swollen lymph nodes include: cat scratch fever