How To Treat Pain And Discomfort In Testicle Due To A Lump?

My son had a a small lump on his left testical when he was 13. He was seen by his gp who said it felt like a cyst, but said he would refer him to see a consultant , he is 27 now and this lump has got a bit bigger and there is also one on the right side to. He says they feel gritty and don't move around. If he try's to move them they will cause pain and discomfort for a day or two. And some times they will flare up them selfs and cause a lot of discomfort.