Types of stage 0 breast cancer
There are two types of stage 0 breast cancer:
Ductal carcinoma in situ (DCIS) occurs when breast cancer cells develop in the breast ducts. Today, stage 0 DCIS is being diagnosed more often because more women are having routine mammogram screenings. DCIS can become invasive,
so early treatment can be important.
Lobular carcinoma in situ (LCIS) occurs when abnormal cells develop in the lobules. These cells are not cancerous and
this condition rarely becomes invasive cancer. However, women who develop LCIS may be at increased risk for developing breast cancer in the future. For women who develop LCIS, the risk of getting an invasive cancer is 20 - 25 percent
over 15 years after the initial diagnosis.
Stage I breast cancer
Stage I breast cancer is the earliest stage of invasive breast cancer. At this stage, the cancer cells have spread beyond the
original location and into the surrounding breast tissue.
Because a stage I tumor is small, it may be difficult to detect. However, breast self-exams and routine screening are always important and can often lead to early diagnosis, when the cancer is most treatable.
Types of stage I breast cancer
Stage I is divided into two categories:
Stage IA: The tumor measures 2 cm or smaller (about the size of a pea or shelled peanut), and has not spread outside the
breast.
Stage IB: Small clusters of cancer cells measuring no more than 2 mm, are found in the lymph nodes, and either there is
no tumor inside the breast, or the tumor is small, measuring 2 cm or less.
The survival rate for stage IA breast cancer may be slightly higher than for stage IB. However, all women with stage I
breast cancer are considered to have a good prognosis.
Stage II breast cancer
Stage II breast cancer indicates a slightly more advanced form of breast cancer. At this stage, the cancer cells have spread
beyond the original location and into the surrounding breast tissue, and the tumor is larger than in stage I disease. However, stage II means the cancer has not spread to a distant part of the body.
At stage II, a tumor may be detected during a breast self-exam as a hard lump within the breast. Breast self-exams and
routine screening are always important and can often lead to early diagnosis, when the cancer is most treatable.
Types of stage II breast cancer
Stage II is divided into two categories:
At stage IIA, one of the following is true:
There is no tumor within the breast but cancer has spread to the axillary (underarm) lymph nodes, or
The tumor in the breast is 2 cm or smaller and cancer has spread to the axillary lymph nodes, or
The tumor in the breast measures 2 - 5 cm but cancer has not spread to the axillary lymph nodes
At stage IIB, one of the following is true:
The tumor measures 2 - 5 cm and cancer has spread to the axillary lymph nodes, or
The tumor is larger than 5 cm but cancer has not spread to the axillary lymph nodes