"Screening is always a double-edged sword," said Dr. Otis Brawley, the chief medical officer of the American Cancer Society.
"We need to be more cautious in our advocacy of these screening tests."
In part, doctors and patients are stuck in a sort of cancer time warp.
The disease was defined in 1845 by a German doctor, Rudolf Virchow, who looked at tumors taken at autopsy and said cancer is an uncontrolled growth that spreads and kills. But, of course, he was looking only at cancers that killed. He never saw the others.
“Now we are backing away from that,” Dr. Brawley said.
In recent years, researchers have found that many, if not most, cancers are indolent. They grow very slowly or stop growing altogether. Some even regress and do not need to be treated — they are harmless.
“We are going from an 1845 definition of cancer to a 21st-century definition of cancer,” Dr. Brawley said.
Dr. Brawley, too, noticed that more people are starting to understand the limitations of screening, and its risks.
-Gina Kolata, "News Analysis: Considering When It Might Be Best Not to Know About Cancer," New York Times, October 29, 2011-
For Part I of this post, click here.
If you received this post via email, and you're unable to view the videos, go to the web version, here.
So, do you still need a little more informaton before you decide if you're ready to make the switch to an every-other-year mammogram? Or, to feel comfortable waiting until age 50 before you start having mammograms?
It can't hurt to know a little more, right?
Maybe the results of two recent studies published on October 18, 2011 in the Annals of Internal Medicine will help you sort out the pros & cons?
The Bottom Line: According to these two Annals of Internal Medicine studies, there's no one size fits all. And who can argue with that one?
You have to consider your own health risks, your tolerance for the anxiety & worry over false-positives, and your willingness to bear the risks of overdiagnosis or overtreatment for indolent/innocuous cancers. But unless you're aware of the risks & benefits you can't make an informed decision. Combine this information with that of my previous post's, and then talk to your doctor. It looks to me like every-other-year is going to be a good decision for me.
I hope this will help!
- Watch the 2 videos below, produced by the Annals of Internal Medicine. They're short.
- Then take a look at the Summaries for Patients produced by the Annals of Internal Medicine. They're lay-language explanations of the studies. Kudos to the American College of Physicians!
1. "The Benefits and Harms of More and Less Frequent Screening Mammography" Click here to read this quick easy-to-understand research summary.
2. "The Accuracy of Film Versus Digital Screening Mammography" Click here to read this quick easy-to-understand research summary.
What the research found:
- False-Positive Mammography Results on the annual versus two year plans: After 10 years, more than 60% of the women who were on an annual mammogram schedule had false-positive results, with a need for additional imaging or a biopsy. Women who were screened every 2 years had 41% false-positive results. But, there was a small statistically insignificant increase in the diagnosis of late-stage breast cancer on the 2 year screening plan. Yes, statistically insignificant. The study found that getting screened every 2 years will decrease the probability of getting called back for repeat imaging & biopsies because of false-positives. The article is here.
- Film Versus Digital Mammography Screening: Both digital & film screening had similar cancer detection rates in proportion to early-stage breast cancers diagnosed. Digital screening had higher sensitivity in women with dense breasts & it was better at detecting the harder-to-treat estrogen-negative cancer. However, the specificity was also lower for ages 40-47 than for the older age ranges. The article is here.
Breast Cancer Prevention Strategies I Omitted on My Previous Post! Shame on me:
- Does Diet Matter in Breast Cancer? Yes, say two MD Anderson Center dietitians. A big thank you to blog reader Doug for sending the CNN link to me. You can read what these saavy dietitians have to say below.
- Vitamin D for breast cancer protection. I left vitamin D out of my previous post, and a DVM/MPH reader reminded me about its importance. According to one recent UCSD study that reviewed 11 observational studies, a serum 25(OH)D level of 47 ng/mL was associated with a 50% lower risk of breast cancer. It may take more than 800 IUs of vitamin D/day to get up to 47 ng/mL, especially if you live up North! Click here and here to read more.
What about the vitamin D cancer connection? It seems so far-fetched. (read more here)
Dr. Bruce Hollis of the Medical University of South Carolina has collaborated with Dr. Walter Willett and the Harvard School of Public Health for over 15 years, studying epidemiologic data on the effects of vitamin D on cancer. These studies have routinely shown that an adequate vitamin D status protects against 13 or 14 different cancers, including breast, prostate, and colon cancer.
Hollis is skeptical that vitamin D could treat cancer once you get it--its benefit is in preventing it in the first place--and having adequate levels will lower your risk.
Researchers in Nutrition Reviews project that a vitamin D blood level over 52 ng/mL would reduce breast cancer by 50%, and levels over 34 ng/mL would prevent 50% of the colon cancers. (Note: a more recent study put the number at 47 ng/mL)
Here's how it works: Vitamin D helps control cell growth and that's why we think that it will reduce the risk of many deadly cancers like prostate, breast, and colon by as much as 50 percent. In its role as a hormone, vitamin D travels all over our body delivering messages to activate genes and control cell growth.
If a cell turns cancerous, vitamin D delivers the instructions for that cell to self-destruct. Not enough vitamin D and that cancer cell might keep reproducing. According to Hollis, "vitamin D acts as a brake" when it comes to cancer. It prevents cells from growing wildly out-of-control--and this mechanism has been studied for years.
- Avoiding unnecessary diagnostic radiation whenever possible. More than a few readers asked me why I didn't mention "avoiding unnecessary radiation" as a prevention strategy in my last post. I just forgot. Here's what breast cancer surgeon & spokesperson, Dr. Susan Love has to say about it: “Don’t get that X-ray unless it’s absolutely necessary. Stay away from unnecessary radiation--so if somebody orders an X-ray, you've got to say, 'How is this going to change my care?' And if it’s not, don’t do it."
The Annals of Internal Medicine: What Are the Benefits & Risks of Women's Cancer Screenings
Listen to Dr. Christine Laine, MD, MPH, the editor-in-chief of the Annals of Internal Medicine discuss the latest research on women's cancer screenings--2:43 minutes.
If you do not see the video on your screen, click here
Listen to Dr. Rebecca Hubbard, co-author of both recent mammography studies, discuss the latest research on "The Benefits and Harms of More & Less Frequent Screening Mammography"
If you do not see the video on your screen, click here
The MD Anderson Cancer Center's Recommendations for a Diet to Reduce the Risk of Breast Cancer
After I wrote my post about mammography--that included just a little bit about the strategies we can all use to help prevent breast cancer--a reader sent me a link to Dr. Melina Jampolis' excellent CNN article, "Does Diet Really Matter in Breast Cancer", October 28, 2011.
To find out if diet made a difference in breast cancer, Jampolis went straight to the experts, registered dietitians Sally Scroggs, MS,RD,LD, and Clare McKinley, RD,LD, who work at the University of Texas M.D. Anderson Cancer Center, one of the leading cancer hospitals in the world.
And here's what they had to say:
Does Diet Really Matter in Breast Cancer?
Written by Dr. Melina Jampolis
"Since October is Breast Cancer Awareness month, this is the perfect time to answer this question.
And the answer is a resounding yes. To get you the best possible information, I turned to registered dietitians Sally Scroggs, MS,RD,LD, and Clare McKinley, RD,LD, at the University of Texas M.D. Anderson Cancer Center, one of the leading cancer hospitals in the world. They explained that breast cancer risk could be decreased by up to 38% through lifestyle factors including maintaining a healthy weight, exercising regularly, and eating a healthy diet. In fact, less than 10% of breast cancer appears to have a genetic basis.
1. Limit Alcohol. For prevention of breast cancer, limiting alcohol to one drink a day (5 ounces of wine, 12 ounces of beer, or 1.5 ounces of spirits) is one of the most important things that you can do. In addition, a plant-based diet loaded with at least two cups a day of a variety of produce is beneficial.
2. A Whole Food Plant-Based Diet is Best. It's Synergistic. According to the American Institute for Cancer Research, "no single food or food component can protect you against cancer by itself. But scientists believe that the combination of foods in a predominantly plant-based diet may. There is evidence that the minerals, vitamins and phytochemicals in plant foods could interact in ways that boost their individual anti-cancer effects. This concept of interaction, where 1 + 1 = 3, is called synergy."
3. The Best Cancer-Fighting Fruits & Vegetables. Some of their top picks for cancer prevention include beans, berries, cruciferous vegetables (broccoli, cauliflower, cabbage, brussels sprouts), dark leafy green vegetables (spinach, kale, chard, romaine, mustard greens), flaxseed, garlic, grapes/grape juice, green tea, soy, tomatoes and whole grains. A recent study in mice suggests that walnuts may also play a role in breast cancer prevention, but these findings need to be confirmed in humans.
4. Curcumin--a possible cancer-fighting spice. There is also a growing body of research suggesting that curcumin, one of the active components of curry, may play a role in both the treatment and prevention of various types of cancer including breast cancer.
5. Weight Matters. Lose It! Being overweight is strongly associated with the risk of postmenopausal breast cancer. Adult weight gain of 22-44 pounds is associated with a 50% greater risk and a weight gain above 45 pounds is associated with an 87% increased risk.
6. Banish the Belly Fat. Excess belly fat seems to be particularly harmful, most likely because of its effects on inflammation and its association with elevated insulin levels, so if you tend to be more "apple shaped" and carry extra weight in your belly, it is especially important to lose weight, exercise regularly, and limit refined grains, sugar sweetened beverages, and added sugar in your diet.
7. Whole Soy Foods are OK--Limit Processed Soy or Soy Protein Supplements. When it comes to breast cancer survivors, a healthy lifestyle is just as important, if not more so. Many women are concerned about soy consumption, which I've written about before. Sally and Clare agree that up to three servings per day is safe, but they emphasize that soy should come from whole foods like soy milk, edamame and tofu, and that supplements like smoothies, bars and soy fortified cereals should be limited.
8. Supplement? Should I or Shouldn't I? Finally, during treatment, diet is very important to maintain health and optimize energy levels, but before taking any supplements, it is best to consult with a registered dietitian, preferably one that has experience with cancer treatment, because some supplements may actually interfere with chemotherapy or radiation.
In general, the emphasis should be on whole foods rich in anti-oxidants. Vitamin C may need to be supplemented in some cases if not enough is consumed in the diet. To find a registered dietitian, go to the American Dietetic Association website.
I hope you are encouraged by the fact that you can make a difference in your risk of breast cancer through lifestyle. Here a few breast cancer fighting recipes from M.D. Anderson to get you started in the right direction." (reprinted from CNN: "Does Diet Really Matter in Breast Cancer?" by Dr. Melina Jampolis, physician nutrition specialist.)
Dr. Joel Fuhrman Weighs in on Breast Cancer Prevention, Too!
Don't miss Dr. Joel Fuhrman's just-posted "tell us what you really think" breast cancer article. Find it on his Disease Proof blog: "October was Breast Cancer Awareness Month, Didn't You Hear?"
Here's an excerpt:
Is there anyone out there who has never heard of Breast Cancer?
Do you want to know why it wasn’t called Breast Cancer Prevention Month?
I’ll tell you why, because its purpose is not to help women by preventing breast cancer; it is all about money.
If the main purpose is saving women’s lives, I would prefer that we call it Breast Cancer Prevention Month!
I couldn't agree more!