Breast Cancer

Breast Cancer

Substantial investment in breast cancer research has led to advances in screening, treatment, and prevention over the last four decades. As a result, over 90 percent of breast cancers are diagnosed at an early age, surgery has become less invasive, and the development of more effective therapies have boosted cure rates to current highs. Crucial insights from genetics research have also led to new, preventive drugs and surgeries that have helped to reduce the risk of occurrence for women who are at high risk for the disease, including those predisposed as a result of genetic mutations.

Today, nine out of ten women are alive five years after diagnosis and mortality has fallen by more than a third since the 1980s. However, more research is still needed to develop better treatments for advanced stages and currently resistant forms of breast cancer, and to address profound racial disparities in breast cancer mortality. 

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1999

First targeted anti-breast cancer drug, trastuzumab (Herceptin), has major impact on care

First targeted anti-breast cancer drug, trastuzumab (Herceptin), has major impact on care

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The FDA approves the groundbreaking drug trastuzumab (Herceptin) after research shows that adding the monoclonal antibody to chemotherapy dramatically increases survival for women with advanced breast cancer that over-produces a protein called HER2. In 2006, the drug is also approved as part of adjuvant therapy (after surgery) for women with early-stage HER2-positive breast cancer, after two major trials show that it reduces the risk of recurrence by more than 50 percent, an unprecedented result.

About 25 percent of breast cancer patients have HER2-positive disease, and prior to the introduction of trastuzumab, there were no effective treatments for these cancers, which were considered some of the most aggressive, deadly forms of the disease. Recently, trastuzumab was also FDA-approved to treat patients with stomach cancers that have a similar over-production of the HER2 protein.

1998

Chemotherapy before surgery helps more women benefit from breast-conserving treatment

Chemotherapy before surgery helps more women benefit from breast-conserving treatment

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A major trial reports that an approach called neoadjuvant chemotherapy – providing chemotherapy before surgery – allows more than two-thirds of women with large breast tumors to undergo breast-conserving surgery, called lumpectomy, instead of full mastectomy. The goal of neoadjuvant therapy is to shrink tumors so they can be removed surgically. Breast-conserving surgery, also called lumpectomy, is easier to recover from and results in far better cosmetic outcomes – without compromising survival – compared with mastectomy. Neoadjuvant therapy is later shown to benefit patients with rectal and other cancers.

Drug therapy can reduce breast cancer risk in women at high risk

Drug therapy can reduce breast cancer risk in women at high risk

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The FDA approves tamoxifen (Novaldex), a hormonal drug already used to prevent recurrence of breast cancer, to reduce the risk of developing breast cancer in women who are at high risk for the disease. The approval is based on a large trial showing that tamoxifen reduced breast cancer risk by more than 40 percent in women with a strong family history of breast cancer or with mutations in the BRCA1 and BRCA2 genes. Later research shows that a different drug used to treat osteoporosis, raloxifene (Evista), is as effective as tamoxifen at preventing invasive breast cancer, but with a lower risk of certain side effects.

Oral chemotherapy drug, capecitabine, approved for advanced breast cancer

Oral chemotherapy drug, capecitabine, approved for advanced breast cancer

Capecitabine (Xeloda) becomes an important treatment option for women whose breast cancer has progressed despite other commonly used forms of chemotherapy. The drug is approved by the FDA based on studies demonstrating the drug slows cancer progression. Unlike other traditional chemotherapies that are administered intravenously, capecitabine is administered orally – a convenient alternative that requires fewer doctor's visits for patients with advanced cancer.

1996

Sentinel lymph node biopsy introduced to assess breast cancer spread

Sentinel lymph node biopsy introduced to assess breast cancer spread

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An important study establishes a technique called sentinel lymph node biopsy as a standard part of breast cancer surgery. The procedure involves removing the lymph node closest to the primary tumor – the "sentinel" node – and examining it under a microscope for evidence of cancer. If the sentinel node is cancer-free, no further lymph nodes are removed and the patient is spared the previous practice of removing a large number of nodes and possibly larger sections of the breast. This more conservative approach allows for easier recovery and reduces the risk of postoperative side effects such as lymphedema, a painful swelling of the arm. If cancer is found, additional nearby lymph nodes are assessed, and often removed, and the patient is treated with additional chemotherapy after surgery. Recently, studies have shown that for some women, removing just the sentinel node may be sufficient.

1995

Bone-building drugs help reduce complications of breast cancer and its treatment

Bone-building drugs help reduce complications of breast cancer and its treatment

For women with advanced stages of breast cancer, it is common for their tumors to spread to the bones, increasing their risk of bone fractures and causing significant pain. In the mid-1990s, a class of drugs called bisphosphonates, originally designed to treat osteoporosis, are proven to prevent and treat these bone-related complications.

Bisphosphonates are also introduced as an option for younger women whose breast cancer treatment induces early menopause. In these women, bisphosphonate treatment following breast cancer surgery is proven to prevent the loss of bone strength, a relatively common side effect of early menopause.

1994

Taxanes emerge as vital chemotherapy option for breast cancer

Taxanes emerge as vital chemotherapy option for breast cancer

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Paclitaxel (Taxol), a chemotherapy drug, proves highly effective for treating advanced breast cancer in women whose disease continues to grow after treatment with other drugs. The drug is later shown to slow cancer growth and extend survival for women with early-stage breast cancer when added to chemotherapy with the drugs doxorubicin (Adriamycin) and cyclophosphamide (Cytoxan).

The drug, which was first proven effective against ovarian cancer, is derived from the bark of a yew tree, and is the product of a field of research exploring 'natural' products for treatment of a range of diseases. Until drugmakers discovered a synthetic method for producing the drug, there was widespread concern that the natural resources needed to produce the drug would not meet demand.

BRCA1 and BRCA2 gene mutations linked to increased breast cancer risk

BRCA1 and BRCA2 gene mutations linked to increased breast cancer risk

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Researchers discover that women who have mutations in the genes known as BRCA1 and BRCA2 have a 50 to 85 percent increased risk of developing breast and ovarian cancers. These mutations are found to be particularly common among women of Ashkenazi Jewish descent. The identification of this important genetic cancer risk factor enables women with these mutations to undergo more frequent screening, and in some cases to undergo preventive surgical removal of the breasts, ovaries or both. Preventive use of tamoxifen (Novaldex) or raloxifene (Evista) becomes an additional option after the drugs are proven effective for this purpose in the following years.

1986

Tamoxifen reduces breast cancer recurrence

1977

Breakthrough drug, tamoxifen, receives initial FDA approval

Breakthrough drug, tamoxifen, receives initial FDA approval

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The chemotherapy drug tamoxifen (Novaldex) is approved for the treatment of advanced breast cancer, based on studies showing the drug caused significant tumor shrinkage. Tamoxifen blocks the activity of estrogen, a hormone that fuels the growth and spread of many breast tumors. Over the next two decades, the FDA approves additional uses of tamoxifen, including as a preventative for breast cancer, based on clinical trials that provide a deeper understanding of which women are most likely to benefit. Researchers also learn that the drug is only effective in women whose tumors contain receptors for the hormones estrogen and/or progesterone – a finding that spares women without these receptors from the unnecessary side effects of the drug.

Growing use of mammography saves lives

Growing use of mammography saves lives

Regular breast cancer screening with mammography becomes increasingly common, helping to detect cancers at an earlier, more treatable stage. By the mid-1980s, nearly one-third of U.S. women over age 40 are screened. By 2008, the proportion screened approaches 70 percent. High screening rates – and resulting early detection – have contributed to a 27 percent reduction in breast cancer mortality among U.S. women since 1975.

Many women can opt for breast-conserving surgery

Many women can opt for breast-conserving surgery

Studies show that a procedure called lumpectomy – involving the removal of only the tumor, and not the entire breast – followed by radiation therapy is as effective as mastectomy for women with early-stage breast cancer. The finding helps dramatically reduce the physical and cosmetic side effects of breast cancer treatment and enables women to recover more quickly after surgery and return to their normal lives.

Estrogen receptor status proven to predict risk of breast cancer recurrence

Estrogen receptor status proven to predict risk of breast cancer recurrence

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Researchers had long known that reproductive hormones play a role in breast cancer growth. But in 1977, investigators first demonstrate that tumors that grow in response to estrogen (known as estrogen receptor-positive disease) are less likely to recur soon after surgery than tumors that are not affected by estrogen (estrogen receptor-negative disease). This discovery helps doctors determine which women need more aggressive treatment following breast cancer surgery, including chemotherapy or radiation.

1975

Adjuvant chemotherapy increases cure rates for early-stage breast cancer

Adjuvant chemotherapy increases cure rates for early-stage breast cancer

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After overcoming concerns in the cancer community about whether the benefits outweigh the risks, Drs. Bernard Fisher and Gianni Bonadonna demonstrate that chemotherapy after surgery – known as adjuvant chemotherapy – prolongs the lives of women with early stage breast cancer. Their studies explore use of the drugs 1-phenylalanine mustard or a combination of cyclophosphamide, methotrexate and fluorouracil. Over time, adjuvant chemotherapy becomes a major component of treatment for the disease, improving survival and cure rates in the years ahead. Today, about 9 in ten women with early stage breast cancer are alive five years after their diagnosis.

This research also sets the stage for research on adjuvant therapy in other common cancers, including colon and lung cancer, making it one of the most important advances in modern cancer care.

1974

Doxorubicin active against advanced breast cancer

1971

More limited mastectomy proven effective for early-stage breast cancer

More limited mastectomy proven effective for early-stage breast cancer

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While radical surgery had been routinely used to treat breast cancer, a more limited surgical procedure called total mastectomy (removing just the breast tissue instead of removing the breast, chest wall muscle and underarm lymph nodes) is confirmed to be as effective for women with early-stage breast cancer. The procedure reduces pain after surgery and speeds recovery for patients. This advance paves the way for future breast-conserving surgeries.