how those breast cancer start?

I have read in one newspaper that commonly woman who has breast cancer may have no problems. Sometimes, however, she may find a painless lump in her breast. I know that if women examine their breasts monthly, they can help find lumps that a doctor should examine. Now I have a question that especially interests me. I would like to hear how does breast cancer start.

First, I have to tell you that most breast lumps are not cancer. However, all lumps should be checked out by a doctor to be sure diagnosis is not dangerous. Non-cancerous breast lumps may be scar tissue or cysts, which are fluid-filled lumps or sacs. Those breast lumps can be due to normal breast changes associated with hormone changes or aging. When a lump is found, the doctor will want to test it, so the best way to do this is usually with a biopsy. The biopsy may be benign, which means the lump is not cancer. If the biopsy shows cancer cells, the lump is malignant. If a breast lump contains cancer cells, the woman will, decide together with her doctor and family, what to do next. For the beginning, you need to know that breast cancer start with lump, so further searching is recommended.