Research on breast cancer is leading to new approaches to treatment and increasing the survival rate. A greater understanding of the molecular biology of breast cancer is helping doctors match patients and treatments more effectively, resulting in targeted therapies that everyone hopes will improve survival. Here’s what you need to know to be up to date…
Two drugs, tamoxifen (Nolvadex) and raloxifene (Evista), can reduce the risk of developing breast cancer in women who are known to be at increased risk of developing the disease (for instance, those with a family history). These drugs are selective estrogen-receptor modulators, which block the estrogen receptor from allowing estrogen to attach to breast tissue and reduce the risk of a hormone-sensitive cancer (about two-thirds of all breast cancers). For high-risk women, they reduce the odds of cancer by about 50%. Pros and cons…
Tamoxifen reduces risk for both an early form of breast cancer, called ductal carcinoma in situ, and also for invasive cancer that spreads beyond the milk ducts. Drawback: Tamoxifen can raise risk for uterine cancer, cataracts, blood clots and stroke. It’s approved for use in women of all ages.
Raloxifene reduces only the risk for invasive cancer and has slightly fewer side effects. It can cause leg pain and reduced libido, however. Raloxifene hasn’t been approved for use in premenopausal women.
Postmenopausal women have a choice as to which drug to use now that raloxifene is available in addition to tamoxifen. The benefit of taking either drug for the recommended five years persists for a long time — at least 10 years — after you stop taking either one.
Bonus: Both drugs help reduce osteoporosis risk.
One of the major findings of the past few years is that not all breast cancers are the same. There are at least five different kinds, and each has its own characteristics, prognosis and response to therapy. Research suggests that the type of cancer is more important than the stage in determining which therapy is likely to be most effective. For instance, testing of a certain type of tumor, such as an estrogen-receptor-positive tumor, can determine whether it will respond to chemotherapy or hormonal therapy. Targeting the therapy to the particular cancer saves many women from unnecessary treatments, and the treatments they do get are likely to work better.
DRUGS TO PREVENT RECURRENCE
Tamoxifen has also been the standard drug for preventing recurrence in women who have had estrogen-receptor-positive breast cancer. Although there are risks, they’re not that high compared with the benefit. Tamoxifen has been around for at least 20 years, and it’s very well understood.
Newer drugs called aromatase inhibitors (AI) — which include letrozole (Femara), exemestane (Aromasin) and anastrazole (Arimidex) — are now also an option for preventing recurrence. These drugs work in a completely different way than tamoxifen. They block an enzyme involved in making estrogen. Their side effects are also different. AI drugs increase the risk for osteoporosis and cause joint and muscular aches and pains.
These drugs have been in use for about five years, so it’s too soon to tell whether they provide long-term protection against recurrence and what the long-term side effects will be. Research is ongoing as to the optimal type of treatment and its duration.
Radiation is a standard treatment for preventing breast cancer recurrence after lumpectomy. As the equipment has improved, doctors have been able to target the radiation more closely to just the area around the tumor, where recurrence is most likely. The better targeted the radiation, the less damage is done to surrounding tissue. Two interesting approaches being studied…
Intraoperative radiation. This involves removing the tumor surgically and giving the area around the tumor a dose of radiation while the patient is still on the operating table. It is definitely convenient and is being studied for its effectiveness.
Local therapy. After surgical removal of the tumor, a balloon is placed into the empty cavity in the breast where the tumor was located. Local radiation “seeds” are then instilled into the balloon for several days and the balloon is then removed.
Both techniques may be good alternatives to the standard six to seven weeks of daily radiation treatments, especially for older women or women with chronic conditions who might find longer radiation techniques too debilitating and otherwise choose total mastectomy. They’re both experimental and are available as part of studies of their effectiveness, so it is worth asking your doctor about them.
There are many positive developments in breast cancer treatment. For more information on the newest treatment options, check our Web site, www.dslrf.org. If you’ve recently been diagnosed, remember it’s not an emergency. Don’t panic — most women who get breast cancer don’t die from it. Take the time to understand your options and find a doctor who’s up on the very latest research.
