Left Saline Breast Implant: Shooting Pain when Breathing, Lump in Center of Breast. What Does This Mean?

I have saline implants that are appraoching 8 yrs old. I have a lump in the same place on each implant: directly in the center of each breast. When I asked surgeon about this several years ago, he said that scar tissue had likely formed around the port used to fill up the implants during surgery. About 2 yrs ago I stared feeling pain when breathing or lying on my left side.This lasts for a few days then goes away, comes back every 8wks. I can feel the lump when I touch it but it is not visible.