Breast Cancer Recurrence?

Sometimes breast cancer comes back. That's why doctors prescribe treatment to reduce the risk of recurrence after surgery.

Treating breast cancer is all about managing risk. By striving to understand how risk changes with treatment, doctors say women are best able to make good decisions in the management of their disease.

When a person has breast cancer and is treated with surgery, there's always the possibility the disease will recur.

The actual risk is highest for the first few years. Therefore, it's important to begin treatment to combat the return of disease as soon as possible.

The range of risk of recurrence with early stage disease can be anywhere from 5 percent for a 5 millimeter invasive breast cancer to as much as 70 to 80 percent for a woman who has eight to ten lymph nodes involved.

Your risk is dependent on the characteristics of the cancer and the stage of the cancer.

The stage of the cancer is a rating based on three factors, and it's often determined after surgery.

Staging of cancer is the concept of classifying tumors based on their size, extent of local spread as well as extent of systemic spread.

For example, for breast cancer, staging depends on the size of tumor, the presence or absence of lymph node involvement and the presence or absence of metastatic disease.

Staging assesses risk using broad strokes. Doctors take a variety of data and circumstances into account as well, what are called "prognostic factors."

With regards to tumor-related factors, focus is not just on tumor size and nodal status, but also on grade. How aggressive is the cancer histologically?

With regards to the woman herself, we focus on her age. Data shows us that women diagnosed with breast cancer under 35 have a significantly worse prognosis than same-size cancers that are diagnosed in an older woman.

When cancer returns, it can be in the breast where it first was diagnosed, in the other breast, or elsewhere in the body.

To reduce the risk of recurrence in the original breast, women who undergo lumpectomies usually receive radiation treatment.

There is ample data to suggest that if a woman has a lumpectomy and does not proceed with radiation therapy, the risk of local failure in the breast is quite high, as high as 30 to 35 percent.

What radiation does is by radiating the breast it limits the risk of that failure.

Women with lumpectomy and radiation have maybe a 5 percent risk of local recurrence versus the 30 to 35 percent that they would have if they had not had radiation.

Other therapies reduce the risk of recurrence in other parts of the body.

In order to reduce risk of recurrence, one has to think of therapies that are systemic in nature, and they are often called adjuvant therapies, or after-the-fact therapies, that focus on eliminating microscopic sites of disease.

A common systemic treatment is chemotherapy.

The risk reduction for chemotherapy, based on the worldwide overview, which looked at all of the randomized studies done through to the year 2000, is 24 percent each year.

In addition, that adds up to about a one-fifth to one-quarter reduction in risk at five years. Again, what that means is, if you have a high risk — let's say a 40 percent risk of recurrence — you might gain ten percentage points in your odds.

However, if you had a very low risk — say, 4 percent — you might gain only one percentage point.

Different combinations of chemotherapy agents are used to fight the possible return of cancer. Regimens that use drugs in a class called anthracyclines are the most widely used in the United States.

Research shows the chemotherapy regimens that are the most effective are ones that include drugs in another class, called taxanes.

The prognostic factors to determine risk of recurrence include what's called the "hormone receptor status" of the cancer.

When cancer is "hormone receptor positive," it has receptors on its cells for the hormones estrogen and progesterone. These cancers can be treated with hormonal therapy, which reduces estrogen in the body or blocks its effect on the cancer.

The mainstay of hormone therapy is tamoxifen. Tamoxifen given for five years to women with hormone responsive breast cancer lowers the risk of recurrence by 40 percent each year, and the overall benefit will be close to one-third.

Women who are post-menopausal have another choice in hormonal therapies, a class of drugs called aromatase inhibitors. There are three drugs in this class: Arimidex, Femara and Aromasin.

Arimidex has been approved for adjuvant use against all types of breast cancers including early-stage disease, when the cancer has not spread beyond the breast.

Femara is approved for locally advanced cancer and metastatic cancer.

Moreover, Aromasin has been approved for use against metastatic cancer if tamoxifen has proved ineffective.

New data suggests aromatase inhibitors may have the most impact on risk of recurrence.

We have three large randomized trials as of May of 2004, all of which show the same thing and that is that the risk of an event, being a recurrence of breast cancer in the breast or a recurrence of breast cancer outside the breast is reduced when a woman is on a aromatase inhibitor compared to tamoxifen.

One of those studies, called the ATAC trial, shows Arimidex is more effective than tamoxifen against early-stage disease in post-menopausal women.

The study included 9000 women, done worldwide, 3000 on tamoxifen, 3000 on Arimidex, 3000 on the combination. And it showed that women on Arimidex did significantly better in terms of risk of recurrence and had less of the expected toxicities that we see with tamoxifen: less uterine cancer, slightly less hot flashes, less thrombotic events or clotting.

We did see an increased risk of osteoporosis and slight fracture risk, which seems to be a common phenomenon for the aromatase inhibitors.

Source: Medaus Pharmacy