Autologous stem cell transplant, also known as autologous hematopoietic stem cell transplant (HSCT), is a treatment option used in certain cases of breast cancer, particularly in advanced or high-risk situations. During an autologous stem cell transplant, a patient’s own stem cells are collected from their bone marrow or bloodstream before undergoing high-dose chemotherapy or radiation therapy. These high doses of treatment are aimed at destroying cancer cells throughout the body, including those that may have spread beyond the breast. After the high-dose treatment, the collected stem cells are returned to the patient’s body through a transfusion. These stem cells help replenish the bone marrow and restore blood cell production, which may have been depleted by the intense therapy. Autologous stem cell transplant is often considered in cases where breast cancer has not responded well to standard treatments or has recurred despite previous therapies. It may also be used as part of a treatment regimen to improve the chances of long-term remission or cure, particularly in younger patients with aggressive forms of breast cancer. While autologous stem cell transplant can be an effective treatment option for some patients with breast cancer, it is also associated with risks and potential side effects, including infection, bleeding, fatigue, and damage to healthy cells and tissues. Patients undergoing this procedure require close monitoring and supportive care to manage potential complications.