Lobular carcinoma in situ means that the tumor cells are still confined to the lobules of the breast and have not broken through the ducts or the end of the lobules, including some basement membranes of the alveoli. In theory, metastasis and recurrence will not occur, so the condition of lobular carcinoma in situ is relatively mild. Although the name of lobular carcinoma in situ is called carcinoma, it is not a real carcinoma and usually does not turn into a real invasive carcinoma within a few years, but mostly after 10 or 20 years, or longer. It still has a relatively high percentage of invasive carcinoma occurring at a later stage, so it needs to be actively prevented and treated. However, it usually does not require surgery, radiotherapy or chemotherapy as it does to deal with invasive cancer.