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.
Swollen lymph nodes. Non-Hodgkin lymphoma can cause lymph nodes to become enlarged. When this occurs in lymph nodes close to the surface of the body (such as on the sides of the neck, in the groin or underarm areas, or above the collar bone), they may be seen or felt as lumps under the skin.igns and symptoms of non-Hodgkin lymphoma. Non-Hodgkin lymphoma can cause many different signs and symptoms, depending on where it is in the body. In some cases it might not cause any symptoms until it grows quite large. Common signs and symptoms include: 1  Enlarged lymph nodes.