Partial mastectomy (sometimes called lumpectomy) is a breast-conserving operation in which the surgeon removes the tumour together with some of the healthy breast tissue surrounding it.
Are pregnant and should avoid radiation, or have multiple breast tumours.
A partial mastectomy surgery is done under general anaesthesia, and usually takes one to two hours. At the same time as the breast tissue is removed, lymph nodes are often removed, usually by sentinel node biopsy incorporating a separate small incision under the arm.
For a tumour that is not palpable (not obvious or big enough to be felt), a wire is sometimes placed adjacent to it to allow surgeons to locate and remove it safely. This procedure is called Hookwire localisation. (See link in page 5 of radiology section).
You will probably stay one or two nights in hospital.