i have a large lump in my groin . i can t tell for sure if it is shrinking over the last few days or not ,but i think so. i am under tremendous stress as of late as my son is battling a 4th recurrence of brain cancer and after a stem cell replacement, we have learned his tumor markers are still rising. Needles to say the 4 year battle is taking an emotional toll on myself. I just finished taking antibiotics a week ago for an ear infection and since this ordeal has begun, i have had lumps under my arm pits that usually go away after a week or so. How long should I monitor to see if it shrinks, before going to the hospital.