A combination of chemotherapy medicines often is given after breast cancer surgery for early-stage breast cancer to reduce the risk of the cancer coming back (recurrence). Giving a treatment after surgery is called "adjuvant" -- in this case adjuvant chemotherapy.

A study found that for women diagnosed with early-stage breast cancer that hadn't spread to the lymph nodes, including Taxotere (chemical name: docetaxel) in the adjuvant chemotherapy regimen was a little better than adjuvant chemotherapy that included fluorouracil -- also called 5-FU -- (brand name Adrucil). Still, women who got Taxotere were more likely to have serious side effects or need to stop treatment.

In this study, known as GEICAM, 1,060 women diagnosed with early-stage breast cancer that hadn't spread to the lymph nodes were treated at cancer centers in Spain, Germany, and Poland. All the women had chemotherapy after surgery because of one or more of the factors below, all of which increase the risk of recurrence:

cancer larger than 2 cm (about 4/5 inch)

hormone-receptor-negative cancer

grade 2 or 3 cancer

the woman was younger than 35

All the women were treated with an adjuvant chemotherapy combination that included three medicines. All the women got these two:

Adriamycin (chemical name: doxorubicin)

Cytoxan (chemical name: cyclophosphamide)

They were randomly assigned to get either Taxotere or 5-FU as the third medicine in the combination.

Taxotere is a taxane and weakens or destroys cancer cells by interfering with the ability of cancer cells to divide. 5-FU is an antimetabolite and destroys cancer cells by acting as false building blocks in a cancer cell's genes, causing the cancer cell to die as it gets ready to divide.

In the United States, the combination of Adriamycin, Cytoxan, and Taxotere is sometimes called ACT or TAC (depending on the dose and frequency of each medicine). The combination of Cytoxan, Adriamycin, and 5-FU is sometimes called CAF or FAC (depending on the dose and frequency of each medicine).

About 6.5 years after diagnosis, the women who got adjuvant chemotherapy that included Taxotere more likely to be alive and not have had their cancer come back -- called disease-free survival -- compared to the women who got adjuvant chemotherapy with 5-FU:

87.8% of the women who got Taxotere were alive and didn't have a cancer recurrence

81.8% of the women who got 5-FU were alive and didn't have a cancer recurrence

Still, overall survival was the same for both groups of women.

The researchers calculated that for every 17 women treated with Taxotere instead of 5-FU, one recurrence was prevented during the 77 months of follow-up. Doctors call this figure number-needed-to-treat, or NNT.

Chemotherapy can cause serious side effects, including low white blood cell counts and neuropathy (nerve damage in the hands and feet). Compared to 5-FU, there were fewer breast cancer recurrences when Taxotere was used, but more serious side effects (grade 3 or 4):

28.2% of the women who got Taxotere had grade 3 or 4 side effects, compared to only 17% of women who got 5-FU

women who got Taxotere were more likely to stop treatment because of side effects

The risk of low white blood cell counts (which makes you more likely to develop a serious infection) can be managed with medicines that help keep white blood cell counts high. These medicines are called granulocyte colony stimulating factors; Neulasta (chemical name: pegfilgrastim) and Neupogen (chemical name: filgrastim) are two examples.

A taxane, such as Taxotere, in an adjuvant chemotherapy combination is a generally preferred choice over 5-FU for women diagnosed with early-stage breast cancer that has spread to one or more lymph nodes. This study suggests that Taxotere also may be somewhat more effective than 5-FU for early-stage breast cancer that hasn't spread to the lymph nodes.

If you've been diagnosed with early-stage breast cancer that hasn't spread to the lymph nodes and are going to have adjuvant chemotherapy, you may want to talk about this study with your doctor. Together you can decide on the best chemotherapy choices for you based on your unique situation and preferences.

In the Breastcancer.org Chemotherapy section, you can learn more about the various chemotherapy medicines used to treat breast cancer, how they work, and what to expect during and after treatment.