For patients with breast cancer, it's important to know which stage of the disease they have. Breast cancer stages may indicate the size of a patient's tumor and if the cancer has spread.

It's also key to be aware of different survival rates for women. Read on to learn more.

Stage 0

Patients in this category may have ductal carcinoma in situ (DCIS), which is noninvasive but can possibly turn into invasive cancer.

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Stages 0, 1, 2 and some stage 3 cancers "are treatable and very often curable" using combinations of things like surgery, radiation, chemotherapy and hormone therapy, Stanford University Medical Center professor Dr. Douglas Blayney told Fox News.

Stage IA

A tumor can be as large as 2 cm, the National Cancer Institute (NCI) says.

Stage IB

At this stage, patients may have a tumor as large as 2 cm, along with “small clusters of breast cancer cells” in lymph nodes, the NCI says. Patients with with no tumor discovered -- but that still have these clusters -- are also considered to have Stage IB breast cancer.

Stage IIA

A patient can have a tumor as large as 2 cm, and as many as 3 lymph nodes have cancer, the NCI says. There may also be Stage IIA patients where a tumor hasn't been discovered, but there's cancer in up to three lymph nodes.

Other people in this cancer stage don't have cancer in their lymph nodes, but have tumors between 2 and 5 cm, the cancer institute explains.

Stage IIB

Patients can have a tumor between 2 cm and 5 cm, along with cancer cell clusters in lymph nodes, according to the NCI. It's also considered Stage IIB if someone has a tumor between 2 cm and 5 cm and 3 or fewer lymph nodes have cancer.

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The NCI says another possibility is for someone to have no cancer in their lymph nodes and have a tumor that's bigger than 5 cm.

Stage IIIA

Someone may have a tumor along with cancer in 4 - 9 of their lymph nodes, the NCI says. Patients with no discovered tumors, but have cancer in 4 - 9 lymph nodes, are also in Stage IIIA.

Stage IIIA includes patients who have cancer cell clusters in lymph nodes and tumors bigger than 5 cm, the NCI explains. The category also includes people with tumors larger than 5 cm who have cancer in 3 or fewer lymph nodes.

Stage IIIB

Cancer may have extended to the chest or caused skin issues like an ulcer, the NCI says. As many as 9 armpit lymph nodes could have cancer.

Stage IIIC

Patients in this category either have a tumor or one hasn't been discovered, the cancer institute says. The disease may be in other parts of their bodies, like in at least 10 armpit lymph nodes.

Stage IV

Patients in this category have cancer that's metastasized, meaning it's spread distantly.

What about 5-year survival rates?

The NCI's Surveillance, Epidemiology, and End Results Program (SEER) program online lists relative 5-year survival rates for female breast cancer.

"Relative survival statistics compare the survival of patients diagnosed with cancer with the survival of people in the general population who are the same age, race, and sex" with no cancer diagnosis, it says.

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When female breast cancer is diagnosed when it's localized, the 5-year relative rate is 98.9 percent, according to SEER.

"Localized does not include stage 0, but it is not exactly stage 1 either," NCI spokeswoman Shannon Hatch told Fox News in an email. "Local means confined to breast tissue and fat including nipple and/or areola. Includes some stage II as well."

The relative 5-year survival rate for female breast cancer drops to 85.2 percent if the disease is found when it has extended to "regional lymph nodes," SEER says online. If it's caught when it has already metastasized, the relative 5-year survival rate is 26.9 percent.