Some problems grow so slowly that we almost forget they are there. A small lump on the back is a perfect example, because it sits in a place we never look at in the mirror.
For many people the first sign is not the lump itself but a feeling of pressure when they lean back in a chair or lie down at night. By then the bump may have been growing quietly for years.
Most lumps like this are epidermoid cysts. They form when skin cells get trapped under the surface and keep producing keratin, a soft protein that slowly fills a small sac.
The back is a common place for them because the skin there is thick and full of large oil glands and hair follicles that can easily become blocked.
When a cyst becomes red and swollen, it is a sign that it has become inflamed. This is the moment when many people finally decide to visit a doctor, and it is usually the right decision.
