The breast is comprised of organs called lobules that can make drain and thin tubes called conduits that convey the drain from the lobules to the nipple. Breast tissue likewise contains lymph nodes, fat and connective tissue, arteries and veins. Breast cancer is a cancer that starts in the cells of the lobules or in the different tissues of the breast. The cancer may be of various types. Breast cancer that has spread from where it started in the pipes or lobules to encompassing tissue is called intrusive breast cancer. In incendiary breast cancer, the breast looks red and swollen and feels warm on the grounds that the tumor cells hinder the lymph vessels in the skin.

Breast-conserving surgery is an advanced form of lumpectomy or wide local excision, where just the tumour and a little surrounding breast tissue is excised. Breast-conserving surgery also known as a quadrantectomy or partial mastectomy.

In breast-conserving surgery, the part of breast tissue excised will depend on:

• The size of a tumour and where it is in your breast
• The size of your breasts
• The type of cancer you have 
• The area of surrounding tissue that needs to be removed.

The surgeon will always remove healthy surrounding breast tissue around the cancer part, which will be taken for biopsy to detect the extension of cancer.
If there's no cancerous tissue present in the surrounding healthy tissue, there's less chance that cancer will reoccur.
If cancer cells are seen in the surrounding tissue, more tissue may need to be removed from the breast.

After having breast-conserving surgery, you'll usually be offered radiotherapy to destroy any remaining cancer cells.