I had hodgkins & im done chemo and radiation, my mass in the chest is still present, but no further growth is noticed. why is the mass still present?

Hodgkin: it may just be a necrotic mass due to the therapy. However I would recommend a biopsy to see if there are any alive cells. If yes, then further therapy may be needed

Needs biopsy: of course to say what the mass is. sometimes it is scar tissue, or a cyst of fluid after the tumor has gone but certainly you'd be concerned that it just hasn't totally responded.