I'm 24 and been type 1 for 10 years, I regularly get some form of hard lump/cyst under the skin at the bottom of my back.
I have previously had one serious lump which got to the point of surgery, however every now and again a small lump appears but always manages to sort itself out and die down.
Has anyone got any advice or tips to help keep these at bay or treat at home etc?
Sounds more like a question for your GP than for us fellow diabetics.
If you already had one removed by surgery I suppose they also could tell you its origin?
More than 30 different kind of conditions can cause raised bumps in the skin, so...
All depending on specific root cause/condition, your way to best prevent/treat may be different.