Nearly 140,000 people are diagnosed with leukemia each year in the U.S. Leukemia is the most common type of cancer found in children, including Shannon Tavarez, the 11-year-old who plays Nala in Broadway’s “The Lion King”.

Shannon suffers from a rare type of leukemia known as acute myelogenous leukemia (AML). Early symptoms of the disease—fever, fatigue, paleness, bone and joint pain, and infections—are easy to confuse with more run-of-the-mill illnesses like a cold or the flu. That’s what Shannon’s mother thought.

“I started noticing she was very tired and fatigued, and it wasn’t normal,” Shannon’s mother, Odiney Brown, told ABC News. “The day we found out, we immediately admitted our lives had just changed completely.”

AML can quickly go from bad to worse. In order to recover, Shannon will need a bone marrow transplant, and like so many others with the condition, she now struggles to find a donor. Finding an exact match won’t be easy, either, because Shannon is African American and Hispanic—two highly underrepresented donor groups.

Even in the event that a donor is found, it is likely that Shannon will need additional treatment. “It is generally an aggressive disease that requires chemotherapy,” Shannon’s doctor, Dr. Barbara Asselin of Golisano Children’s Hospital at the University of Rochester Medical Center, told ABC News. “The first hurdle is to see if we can achieve a remission in the bone marrow and don’t see any more leukemia cells.”

Asselin says the chances of recovery are less than other forms of childhood leukemia, but that she remains optimistic about a cure. For now, Shannon is trying to enjoy life as a normal 11-year-old girl, watching movies at home and chatting online with friends between treatments.

Read more from ABC, or find out how to become a donor through the National Marrow Donor Program.

There may be a new prevention method within reach for women at risk for developing breast cancer. The answer lies in a vaccine designed to stop the formation of tumors. The vaccine, developed by doctors from the Cleveland Clinic, has been successful in some animals.

Breast cancer forms in the mammary glands and/or ducts. Tissues in these areas grow and multiply at unregulated rates, forming tumors. The body recognizes these tumors as healthy tissues and will not destroy them as it would a virus. According to the Susan G. Komen Foundation, it could take as long as 10 years before a tumor is large enough to detect.

Most current efforts to treat breast cancer focus on how to destroy or stop the growth of already-present cancer cells using tumor antigens. The problem is that these methods essentially kill the tissues. It can also compromise the autoimmune systems of already vulnerable cancer patients. The Cleveland Clinic's vaccine takes a new approach: It’s designed to stop tumors before they’ve had a chance to develop.

Lead researcher Dr. Vincent Tuohy observed mice predisposed to breast cancer for 10 months. The vaccine targeted alpha lactalbumin, a specific protein found in most breast cancer cells. Half of the mice were given the vaccine, while the other half acted as a control group. At the end of the trial, none of the vaccinated mice had developed breast cancer. All of unvaccinated mice had.

"We believe that this vaccine will someday be used to prevent breast cancer in adult women in the same way that vaccines prevent polio and measles in children," Tuohy said in a Cleveland Clinic press release. "If it works in humans the way it works in mice, this will be monumental. We could eliminate breast cancer."

Although there is still much more to investigate before the vaccine is ready for human trials, the research team hopes to be able to administer the vaccine to women older than 40 and women at high risk in the next 10 years.

Visit the Cleveland Clinic’s website to read the press release, or visit Nature Medicine to read the study’s abstract.

Researchers from Stanford University may have discovered a way to boost fertility by stimulating dormant ovarian follicles. This could benefit women whose reproductive systems have been affected by ovarian cancer or ovarian failure.

The technique involves stimulating dormant ovarian follicles, also known as Graafian follicles. These follicles are small spherical cavities that fill with fluid to develop eggs. Once the egg is developed, the woman ovulates and prepares for fertilization.

If these follicles are damaged, however, a woman may not produce eggs and may experience infertility. Only a small portion of ovarian follicles are used each month, and some remain dormant over the course of a woman’s life. Researchers hoped that by stimulating these follicles, they could boost fertility.

Researchers first tested the technique on mice and were successfully able to produce mature eggs and then pups. They were also able to produce eggs in humans, but did not investigate the technique’s effects on conception.

Experiments are still in the early stages, but these results do provide hope for couples struggling with fertility. Lead author of the study, postdoctoral fellow Jing Li of Stanford University Medical School, says it will be a while before they know whether this method will be as successful in humans as it is in mice.

“We hope that aging women, women who have frozen ovarian tissues prior to undergoing cancer treatments, or women with premature ovarian failure could benefit from our research," Li told Health Day.

Read the original article in Health Day, or visit The Proceedings of the National Academy of Sciences to view the study’s abstract.

If you're having trouble keeping your daughter out of the tanning bed, and talking to her about cancer isn't helping, you may consider stressing wrinkles as a consequence of too much tanning time.

To test the effectiveness of an appearance-based intervention, Dr. June Robinson, professor of dermatology at Northwestern University Feinberg School of Medicine, and her colleagues assembled a 25-page book detailing the history of tanning and the effects it can have on skin and collagen, as well as tanning alternatives. They distributed the booklets to college-aged women (18-22) who tanned as often as four times per week.

These women said they tanned for one of two reasons: To boost mood (symptomatic of seasonal affective disorder), or because they detested their skin color. Six months after reading the booklet, tanning visits among the young women fell by roughly 35 percent and some eventually gave up tanning all together. Why?

“They’re not worried about skin cancer, but they are worried about getting wrinkled and being unattractive,” Robinson said in a press release. “The fear of looking horrible trumped everything else.”

East Tennessee State University’s Joel Hillhouse, Ph.D, was lead author of the report, and wrote the booklet used in the study. He says this experiment was originally meant to serve as an appearance intervention, which means it would have less of an effect on the group with symptoms of seasonal affective disorder (SAD).

"We found the opposite,” he said. “The intervention worked just as well for people with seasonal affective disorder as for people who didn't like their skin color. That means it's a really good intervention for everyone."

That includes your daughter, your niece, or maybe even your sister. According to the Skin Cancer Foundation, the number of women under age 40 diagnosed with basal cell carcinoma has doubled in the last three decades, and the risk of melanoma increases by 75 percent if she has used a tanning bed before age 35. Talking about responsible tanning is important.

The key?

"You have to balance the positive and the negative forces that motivate someone to change," Robinson said. "First you have the fear that they will look horrible, then you offer a positive—an alternative to meet their needs."

Read The Archives of Dermatology for more about the intervention study, or visit the Skin Cancer Foundation’s site to learn more about melanoma.

Do you suffer from recurring sinus problems? If so, a friend's cigarette could be to blame. Two out of five cases of chronic sinusitis may be due to exposure to secondhand smoke.

Sinusitis occurs when the sinuses become swollen or infected. According to Mayo Clinic, sinusitis is usually the result of a cold, allergies or other nasal problems, and can easily be treated with antibiotics, heat (to relieve sinus pressure) or a variety of over-the counter medications.

When the condition persists for more than eight weeks or recurs frequently, this is known as chronic sinusitis. Secondhand smoke contains over 50 known carcinogens; these chemicals can also cause heart problems, asthma attacks and nasal irritation.

Researchers from the Henry Ford Health System in Detroit, recruited 612 non-smokers to participate in a study investigating the relationship of secondhand smoke (SHS) and its source to chronic sinusitis. All had been exposed to SHS for five years prior to the study, and half had been diagnosed with chronic sinusitis (CRS).

Researchers focused on four locations where participants were primarily exposed—home, work, public places and social functions. All showed a marked relationship between secondhand smoke exposure and incidence of chronic sinusitis, especially at social functions (51 percent) and in public places (90 percent).

Although levels of exposure were significantly lower for nonsmokers who had not been diagnosed with chronic sinusitis, study co-author Amanda Holm, MPH, says even modest levels of exposure carry risk.

"The poisons found in secondhand smoke are quite an irritant to the sinus and nasal passages and are a major contributor to the development of rhinosinusitis," Holm said in a press release. “"Our findings reaffirm the health hazards of secondhand smoke."

Visit Mayo Clinic to learn more about chronic sinusitis, or learn more about Holm’s study in The Archives of Otolaryngology.

Summer is here, which means it will soon be time to hit the beach. Every beachgoer knows the importance of sun block, but are all sunscreens the same? Your sunscreen may protect against sunburn, but not all sunscreens provide equal protection from the UVA rays that cause skin to age.

Comparing Apples to Oranges: UVA&UVB Rays

According to The Skin Cancer Foundation, long-wave UVA rays make up about 95 percent of the UV rays that hit Earth. These rays aren’t as intense, but there are 30-50 times more of them, and they’re present year-round in all daylight conditions. UVA rays have deeper penetration, too, and can cause wrinkles, aging, and skin cancer.

Although the effects of UVB rays are more superficial, they can cause serious damage to the epidermis. These rays are responsible for skin reddening and those nasty sunburns you get at the beach. UVB damage is more visible, and can also lead to skin cancer.

SPF: Get to Know Your Sunscreen

“For sunscreen to be really effective in preventing skin cancer, it has to provide broad-spectrum coverage,” Dr. Henry Lim, chairman of dermatology at Henry Ford Hospital, told MSNBC. “The U.S. is the only country with no guidelines for UVA protection, so consumers here have no way of knowing.”

One common misconception about a sunblock’s sun protection factor (SPF) is that the numbers—15, 30, and clear up to 100—indicate the level of protection. In actuality, it represents the amount of time a person can be exposed before the skin starts to redden. Dr. James Spencer, a St. Petersburg, Florida, dermatologist explains:

“SPF is very misleading,” he told MSNBC. “If I were a logical consumer, I would think that SPF 30 is twice as good as SPF 15. But SPF 15 blocks 94 percent of UVB rays. SPF 30 blocks 97 percent. Past 30, there isn’t much additional benefit to be had.”

Where to go from here:

The best thing you can do for your skin is to protect against both UVA and UVB rays.   Seek shade during peek daylight hours (10 am to 2 pm), wear clothing that will cover or protect the skin, and find a sunscreen that has ingredients that protect against both UVA and UVB rays. These ingredients include dioxybenzone, ecamsule, oxybenzone, titanium dioxide and zinc oxide.

Read more about UV rays at MSNBC.com, or contact the FDA about establishing guidelines for UVA protection.

Smoking, heavy drinking, a poor diet, and too much time spent on the couch are bad for your health, but they may also be taking years off your life. These four bad habits could actually be causing your body to age up to 12 years, research suggests.

Nearly 4,900 men and women age 18 or older were randomly chosen to participate in a University of Oslo study examining the effects of certain habits—smoking, excessive alcohol consumption (3 or more drinks for men, and two or more for women), getting less than 2 hours of exercise per week, and not eating well (specifically, not enough fruits and vegetables).

The study began in 1985, and followed participants for 20 years, checking death certificates and doing follow-ups. Of the 314 participants who had all four habits, almost one-third died over the duration of the study, while less than 10 percent of the 387 people who had none passed away.

Heart disease and cancer topped the list for cause-of-death for people who had a combination of these habits, while the health of those still living was “equivalent to being 12 years older” than their healthier counterparts.

Lead researcher Elizabeth Kvaavik thinks these findings may be the extra incentive some people need to improve their lifestyles.

"You don't need to be extreme to be in the healthy category,” Kvaavik said in a news piece by MSNBC. "These (healthy) behaviors add up, so together it's quite good…It should be possible for most people to manage."

Kvaavik and her colleagues acknowledge that changing these habits may not be easy, but that they pay off.

“The combined effect of poor health behaviors on mortality was substantial, indicating that modest, but sustained, improvements to diet and lifestyle could have significant public health benefits,” authors of the study concluded.

Visit the Archives of Internal Medicine to read more on the study.

When it comes to finding the perfect person, forget asking the standard ‘What’s your dream date?’ questions. Now it may be practical to ask which terminal illness he or she has. Prescription4Love.com, a new dating site has been doing just that.

Ricky Durham created the site in 2004 in honor of his brother, Keith. The site is geared to match people with special health needs to others with similar conditions. Whether this search is for friendship or something more is entirely up to the user.

Ricky’s brother Keith had Crohn’s Disease, a form of irritable bowel disorder. It could make meeting people for the first time awkward. That’s when Ricky came up with the idea for Prescription 4 Love.

“Deciding when to tell someone you have a colostomy bag is incredibly difficult,” Durham explains. “I thought if Keith had a chance to meet someone with a similar condition, there would be no need to have to disclose anything.”

Prescription 4 Love is set up like most other online dating sites. Users can create their own profiles, browse through the forums, and chat with each other in an open environment without a hidden medical history. Durham’s recently added instant messaging, blogging and virtual gifts to the mix.

Durham’s site began with a focus on just 11 chronic illnesses, but has expanded to include more than 30. Prescription4Love welcomes anyone from amputees to recovering alcoholics, people with diabetes or heart disease, people who have or have had cancer to little people. Durham has even added STDs to the list. In fact, HIV and herpes are among his most popular groups.

“One lady in particular called me who had cancer said that whenever she told the person she was dating she had cancer they stopped dating her within a matter of days,” he says. Now she can find acceptance in a community where everyone can relate in one way or another.

As of now more than 8,000 people have used the site, and although Keith passed away before the site was fully developed, he is still very much the driving force behind Ricky’s work.

“Keith is the inspiration behind everything that I do for Prescription4Love,” he says. “I have had phone calls and emails from different people thanking me for stating such a web site…the response has been great.”

Cancer and Alzheimer’s appear to be inversely related. That is, people who have had cancer have a decreased risk of developing Alzheimer’s, and vice versa.

The purpose of the study, which appears in Neurology, was to discover whether or not cancer was linked with Alzheimer’s and types of vascular dementia, such as Parkinson’s disease. There was no significant relationship between Alzheimer’s and vascular dementia, but they were able to link cancer and Alzheimer’s disease.

Researchers made adjustments for factors such as smoking, obesity, and physical activity. They also adjusted for hypertension, diabetes, and coronary heart disease. Researchers monitored 3,020 people, age 65 or older, for dementia and cancer, for roughly five and eight years respectively.

“Prevalent cancer was associated with reduced risk of any Alzheimer's disease and pure Alzheimer's disease among white subjects after adjustment for demographics,” authors wrote. “The opposite association was found among minorities, but the sample size was too small to provide stable estimates.”

White participants who’d had cancer before or at the beginning of the study were 43 percent less likely to develop Alzheimer’s disease. In turn, those with Alzheimer’s had a 69 percent decreased risk of developing cancer.

Despite not finding a direct link between Alzheimer’s and vascular dementia, the study does provide implications on its relationship to cancer.

“Together with other work showing associations between cancer and Parkinson disease, these findings suggest the possibility that cancer is linked to neurodegeneration,” authors concluded.

View the study’s abstract in the online version of Neurology.

Your vitamin regimen may be boosting more than your immunity/metabolism. Certain herbal supplements can also increase blood lead levels.

A study in the Journal of General Internal Medicine. investigates the effects different herbal supplements on blood lead levels. Supplements with high heavy metals levels included Ayurvedic herbs, echinacea, ginseng, St. John’s wort, bee pollen, ginko, and nettle.

Lead exposure can result in medical complications, including high blood pressure, kidney disease, cancer, heart disease and peripheral artery disease. High blood lead levels also pose a risk for women planning to become pregnant. Lead can lead to pregnancy complications for both the mother and the developing child.

“Among adults, the potential implications of low-level lead exposure are most relevant to women of child-bearing age,” study authors write. “As lead is especially harmful to developing nervous systems of fetuses and children and passes through the placenta and breast milk.”

Researchers recruited 6,712 Unites States women in good health who were of reproductive age—20 or more years old. Participants self-reported their vitamin regimen for 30 days, and were divided into groups based on the type of supplements they used.

Women who took these supplements had significantly higher lead levels than women who took other herbal medicines. Blood lead levels of women who took Ayurvedic supplements were 24 percent higher than non-users. St. John’s wort wasn’t far behind with 23 percent higher levels.

Greater lead levels were not seen in individuals who used other supplements, such as garlic. Researchers acknowledge that these supplements can have some beneficial effects on personal health, but recommend firmer regulations.

“Our data suggest testing guidelines for herbal supplements,” they write, “and regulations limiting lead in supplements are needed.”