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.
The most common cause of a groin lump is swollen lymph nodes. These may be caused by: Cancer, most often lymphoma (cancer of the lymph system) Infection in the legs. Bodywide infections often caused by viruses. Infections spread through sexual contact such as genital herpes, chlamydia, or gonorrhea.