How far have we come in women’s cancer? Keeping up with the latest treatment trends and studies about cancer of the breast, ovary, uterus, and cervix can be daunting. New studies come out seemingly every week with hot-off-the-press -- and often contradictory -- results. Mammograms? They’re either the key to prevention or misleading at best. And what’s the final word on hormone replacement therapy? Does it prevent or cause cancer? Experts have even recently challenged the value of sticking to a low-fat diet to help keep cancer at bay.
We need answers. An estimated 251,140 U.S. females will battle breast, ovarian, uterine, or cervical cancer in 2007. For a clearer picture of the state of women’s cancer treatment today and tomorrow, WebMD chief medical editor, Michael W. Smith, MD, turned to WebMD’s resident cancer expert, Harold J. Burstein, MD, PhD.
What breast cancer advances are you most excited about?
Two big ongoing trends in breast cancer medicine today offer patients tremendous promise. One is the development of new drugs that target cancer cells directly. Some interfere with specific molecules involved with cancer cell development or tumor growth. Others slow the growth of breast cancer cells that enlarge in response to the hormone estrogen. These drugs work by blocking estrogen’s effect. Still others target the vascular system and block development of blood vessels that help feed the cancer cells.
These drugs are an exciting development for a couple of reasons. One, targeting a cell process that has gone awry allows the treatment to actually get right at the molecular process that has contributed to developing cancer. Second, these treatments have much less effect on normal, noncancerous cells. This usually leads to fewer side effects than with typical chemotherapy.
What is the second trend?
Breast cancer treatment is much more personal than in the past, and we’re able to tailor a woman’s treatment based on the genetic makeup of her own cancer cells. It perhaps sounds obvious, but what we’re finding is that not all breast cancers are the same.
Specific genes in these cells can tell us how the tumor will grow, how likely the cancer is to recur, in general how it will behave. This information helps shape treatment -- how aggressive to be with chemotherapy, for example, or even which patients really need chemotherapy and which patients don’t.
Women hear a lot about the benefits of a low-fat diet and exercise, and popular rumors advocate avoiding chemicals such as those in antiperspirants. What’s your take on breast cancer prevention strategies?
With some cancers, we do know what the major risk contributors are. For instance, we know smoking is directly associated with lung cancer, bladder cancer, head and neck cancer, cervical cancer, and pancreatic cancer.
But with breast cancer, we don’t have such clear risk factors; in fact, most are fairly weak -- such as whether you had children or at what age you first became pregnant, how much you weigh, and how much alcohol you drink. They increase the risk of getting diagnosed with breast cancer only by a little bit. For most women, we don’t really know why they develop breast cancer.
However, the one risk factor that’s different is heredity. It’s clear that women who have a strong family history of breast or ovarian cancer have a greater risk of developing breast cancer themselves.
And we know now that there are at least two specific genes associated with both cancers: BRCA1 and BRCA2.
Common sense suggests that habits such as getting more cardiovascular exercise and eating more fruits and vegetables are good for everyone’s overall health. But it’s not clear that avoiding red meat, going on an all-vegetarian diet, drinking red wine, eating soy or avoiding soy, or similar actions will lower the chances of being diagnosed with breast cancer.
You mentioned genes earlier, and certainly BRCA1 and BRCA2 are in the news. Also, I see the occasional study looking at other genes that may or may not predispose women to breast cancer, or that may point to their getting a more aggressive type. Given this, should women seek out genetic testing or be more proactive in learning about their own genetic profile?
Not really, because breast cancer’s hereditary risk factors probably account for only 5% to 10% of cases. However, genetic counseling may be useful for women who do have several relatives who have had breast or ovarian cancer; or women from families where breast cancer strikes at a very early age, typically younger than 40; or women who have had breast and ovarian cancers -- these all could signal a possible hereditary risk.
What about mammograms? Experts say they are the best detection we have, although not everyone agrees on how effective they are.
Mammography is a remarkably effective tool. That said, it is not a perfect tool, and that’s where the controversy lies. Even though it’s the best screening tool we have, it can still miss breast cancers in some women. And in other women mammograms may indicate something abnormal, but further testing shows there’s nothing to worry about. So some women undergo what some consider to be unnecessary testing, including a possible biopsy.
There is also debate about which women might need something more than a mammogram. For example, some women have dense breast tissue, which makes it more difficult to detect a tumor with a mammogram screening.
Even so, my view is that there’s no question women should get mammograms on a regular basis starting at age 40. There’s no question that the last decade’s decrease in breast cancer death rates in the United States and Western Europe is due in large part to public health programs such as widespread mammography.
The news on the screening front right now is trying to figure out who needs extra testing and what tests we should give. The most commonly discussed “other test” is the MRI, a very sensitive technique that allows a radiologist to look in more detail at breast tissue, to pick up smaller abnormalities that may be difficult to see or may be hidden on a mammogram.
Still, while our threshold for ordering an MRI has gotten lower, not every woman needs an MRI.
Given these new targeted therapies, individualized treatment, and widespread screening, where do you think we’ll be in the near future? What about a cure for breast cancer?
I can tell you where I hope we are. As for a cure, people sometimes imagine we’ll have a magic bullet or a super pill or some other treatment that will make the cancer go away. So far that has proven elusive.
I think that, over the next few years and decades, we’ll continue to devise even more specific, individualized treatments for each woman who is diagnosed with breast cancer. That means that some women will have less treatment, some more.
We’ll also continue to make progress on treatments that have fewer side effects. And I believe we’ll discover more about the risk factors for breast cancer and the behavior of tumors -- both may lead to lower incidence.
Obviously, early detection is key, and that requires more sensitive tools than we currently have. I’m hopeful that we’ll develop increasingly sensitive techniques to catch breast cancer as early as possible.
Let’s move on to ovarian cancer, which is difficult to diagnose and therefore more deadly. What are researchers looking at right now in the fight against ovarian cancer?
You’re right. It has remained a more lethal cancer, for two reasons: One, we’ve lacked good early detection, and two, new treatments have been slow to develop. But we now know that giving chemotherapy drugs directly into the lining of the abdomen means we can target more closely the source of the cancer and also where it’s likely to spread. Emerging data also suggest that newer drugs such as the antiangiogenesis drugs might be valuable for treating ovarian cancer, so that’s an area of active clinical investigation. These drugs essentially starve the cancer by blocking blood supply and depriving the cells of oxygen and nutrients.
Of course, we now have a consensus on early ovarian cancer signs, which are subtle and may not indicate cancer at all. The main value here is to raise awareness of the disease and not to frighten women.
We still need a good tool to catch this cancer earlier. The National Cancer Institute has been sponsoring early detection trials for ovarian (as well as prostate and cervical) cancer for quite some time. Researchers are looking at screening by ultrasound or by a specific blood test, so the results of these trials could someday lead to earlier diagnosis.
What about cervical cancer? The recent HPV vaccine certainly seems to be the biggest news in cancer in recent years. Do you agree?
Absolutely. The HPV [human papillomavirus] vaccine is an amazing breakthrough because it’s the first vaccine targeted against the actual cause of a specific type of cancer. Cervical cancer deaths in the United States are relatively uncommon, though that isn’t true in other parts of the world. Nevertheless, cervical cancer is a great example of how prevention can help. Before the vaccine, the No. 1 prevention tool was the Pap smear. And, like mammograms for breast cancer, fewer deaths from cervical cancer are due to the widespread use of Pap smears, which detect very early precancerous changes.
We know that cervical cancer is a sexually transmitted disease, through the transmission of the human papillomavirus, which is responsible for most cases of cervical cancer. It is also caused by smoking. So now, women can take even more steps to help prevent this cancer. They can quit smoking and exercise careful judgment in sexual activities, get regular Pap smears, and get the vaccine.
Right now, the vaccine is recommended for girls as young as 9 and women up to age 26 who didn’t get it as youngsters. The vaccine is only effective before a woman is infected with HPV, which is why it’s recommended for girls and young women. The vaccine is also being studied for older women and for boys. I would expect a significant decrease in cervical cancer cases 20 years from now.
Uterine cancer is the most common cancer of the female reproductive system, but I don’t hear about it too often. What’s your outlook on this cancer?
It’s typically a disease of older women, and most cases are cured with a hysterectomy. We’ve seen a drop in incidences, largely due to more awareness and more early detection. Another factor is that fewer women are taking HRT [hormone replacement therapy], once a very common treatment for menopausal symptoms. Given all this, I’d expect the decrease in uterine cancer to continue in the years ahead.
We’ve seen a drop in breast cancer cases, but at the same time we know that fewer women may be getting mammograms. The public also appears to be more aware of cervical and ovarian cancers. Overall, what is the prognosis for women’s cancers going forward?
Our best hope is early detection. We’ve seen how that’s made an enormous difference with breast cancer. If we can develop more detection tools for other cancers, the outlook for all will be much better. That’s my best guess at the future right now.
Biography: Harold J. Burstein is an assistant professor of medicine at Harvard Medical School and a medical oncologist in the Breast Oncology Center at Dana-Farber Cancer Institute in Boston. He also serves on the National Comprehensive Cancer Network Breast Cancer Panel, the Cancer and Leukemia Group B (CALGB) Breast Committee, and several working groups on breast cancer in the American Society of Clinical Oncology.
Originally published in the September/October 2007 issue of WebMD the Magazine.