How the Tumor Characteristics of DCIS Affect Treatment Options

Each cancer has a set of specific characteristics that doctors refer to as its personality. DCIS is a group of cancer cells that haven't learned how to break through normal tissue barriers. In this way, DCIS may threaten to cause a problem, like a group of rebellious teenagers. They are showing a lot of attitude, but they haven't yet done anything that's truly dangerous. Doctors may describe the DCIS cancer cells as looking "angry" or "disorganized" as opposed to relatively quiet and easy-going. Pathologists describe these personality features based on a variety of qualities.

Cancer grade:

Doctors give DCIS one of three grades, based on how similar or different the cells are from normal cells.

• Grade I (low grade): These cells are slow-growing and look a lot like normal cells.
• Grade II (moderate grade): These cells grow faster than normal cells and do not look like them.
• Grade III (high grade): These fast-growing cells do not look at all like normal cells.

The higher the grade of DCIS, the higher the risk of having an invasive breast cancer in the future.

Dead cells (necrosis) in the tumor:

The pathologist looks for dead (necrotic) cancer cells in the midst of the tumor. If they are there, it means that the tumor is growing extra fast, and there's not enough blood supply to feed all the cancer cells. As a result, some of the cancer cells have died off.

A pathologist who sees pockets of dead cells may use the terms "punctate necrosis," "high grade," or "comedo" to describe the cancer. The presence of these dead cells means the DCIS is associated with an increased risk of developing an invasive cancer in the future.

Pattern of growth:

DCIS has certain distinct patterns of growth. These patterns tell the doctor which grade the DCIS is. If it is low-grade or moderate-grade, it may be solid, cribriform, or papillary. These specific characteristics show

• how fast- or slow-growing the cancer is
• the risk that it may come back
• if it does come back, whether it is likely to return within five years, or later

Presence or absence of microinvasion:

Although DCIS is a non-invasive breast cancer, there is still the possibility that a few cancer cells may start to break through the wall of the duct. This is called "DCIS with microinvasion." It is considered a slightly more serious type of DCIS. The early signs of invasion are associated with a small increased risk of developing a real invasive cancer that can grow all the way through the wall of the milk duct and spread to other areas.

When microinvasion is found, your surgeon may recommend a sentinel lymph node biopsy to see if there is any lymph node involvement.

It's important to remember that a diagnosis can change from the first biopsy to the final surgery. For example, the first biopsy may show just DCIS. Later biopsies may show an area of invasive cancer (not just microinvasion). When both DCIS and invasive breast cancer are present in the same cancer, the cancer is considered invasive. The DCIS part of the cancer should also be described in the pathology report, but it becomes less important than the invasive cancer.

Hormone receptor status:

If the DCIS is hormone-receptor-positive, your doctor might recommend hormonal therapy (anti-estrogen therapy). This is a type of medicine that reduces the amount of estrogen in your body or keeps estrogen away from the hormone receptors.

In order to find out the hormone status, the DCIS needs to be tested for hormone receptors. Hormone receptors are like ears on breast cells that listen to signals from the hormones estrogen and progesterone.

• An "ER-positive" cancer has receptors for the hormone estrogen.
• A "PR-positive" cancer has receptors for the hormone progesterone.
• An "ER/PR negative" cancer has no such receptors.

Both estrogen and progesterone receptors should be tested. If the DCIS is hormone-receptor-positive, then you might get a significant benefit from taking anti-estrogen therapy.

Testing DCIS for hormone receptors is relatively new, however. Don't assume that your hospital will automatically perform this test. Be sure to ask your doctor to have the cancer tested this way.

If the DCIS has no hormone receptors, a variety of very good treatments are still available.

Possible Change of Stage for Disease

After all of the pathology results come back, the stage assigned to the cancer can stay the same or change. It all depends on the nature and extent of the disease.

The description of each cancer takes into consideration

• size or T (tumor) status
• nodes or N-status
• metastases or M-status

The total TNM information determines the stage.

Your diagnosis may stay "Stage 0, DCIS" throughout the process. You might see "Tis, N0, M0" in your report, which means that the tumor is "in situ" and there is no lymph node involvement or metastasis. Or, if a very small, microscopic area (less than a millimeter) of microinvasion is found, the stage may change to "Tis-mic." If there is mostly DCIS, but there is an area of microinvasion that equals one millimeter, the stage is T1-mic. The category would then be upgraded to Stage 1, but it is the least serious of any Stage I disease.

Of course it's upsetting to learn that what you were told was "just DCIS," the least serious type of breast cancer, is actually more significant. Keep in mind that no matter what is found, your doctors have many effective treatment options to offer you.