THURSDAY, Aug. 7 (HealthDay News) -- Shelley Volz, now 59, got the news about her breast cancer diagnosis 10 years ago, right before she was headed from San Francisco to New York for the wedding of her younger brother.

After much thought, she decided to tell only her mother before the wedding and to hold off telling other family members. "My mother had a typical mother's reaction, tears and hugs, and we moved on," Volz said. "She really appreciated the fact that I didn't want to steal the limelight there."

Volz waited until after the wedding celebration to calmly tell others. Ten years later, after successful treatment, she is doing fine.

While she says she doesn't think she found it as difficult as many people to disclose the diagnosis, she did think about others' reactions.

In that sense, she is typical, according to a new study. "Even when women are facing a breast cancer diagnosis, they are still concerned about caring for everyone else, especially the emotions of others," said study author Grace J. Yoo, a medical sociologist at San Francisco State University's Biobehavioral Research Center.

She presented the findings Monday at the American Sociological Association annual meeting, in Boston. The research is especially timely, given the recent news that actress Christina Applegate, 36, is being treated for early breast cancer.

Yoo and her team interviewed 164 San Francisco-area breast cancer survivors, average age 57, of different ethnicities to evaluate the "emotion work" involved in telling others about the diagnosis.

In interviews with the researchers, the women talked about their feelings and actions after getting the diagnosis.

"Even telling someone, 'I have breast cancer,' it's well thought out," Yoo said. "They know the statement, to some, can overwhelm." Women react in different ways -- stifling their own emotions so they don't appear vulnerable, paying attention to the timing of their news, or sometimes letting it all out, she said.

>Women find it somewhat easier to tell friends than family members, she found. "Women are trying to protect older, aging parents and younger children and even their spouses, even during illness. Women are socialized to care about others."

Ideally, Yoo said, women should do less of that at this time. "It's a time they should be caring about themselves, what decisions they should be making about breast cancer. They shouldn't emotionally burn themselves out by caring for others' emotions."

One woman, for instance, told the interviewer that she didn't tell her mother about her breast cancer until after the surgery, because she knew her mother would worry. Many women said once they were told about the diagnosis, they were surprised about the outpouring of help, even from acquaintances. But some feared that if they told, people may not care enough to help.

The findings ring true with what another expert has seen in clinical practice. This has "documented what we have known instinctively," said Lori Worden, an oncology social worker in Grants Pass, Ore.

Her advice to women? "You don't need to tell people today." Feel free to process it yourself first. Practicing what you will say, by saying it out loud to yourself or writing it down, can help, she said.

Yoo's advice: "We tell women to seek out other breast cancer survivors, other women who understand, to increase their resources." And focus more on getting emotional support than giving it.

More information

To learn more about how to tell others about your diagnosis, visit the Lance Armstrong Foundation  .

WEDNESDAY, Aug. 6 (HealthDay News) -- Physical activity can reduce the risk of colon cancer, but few American adults are aware of this, a new study shows.

A sedentary lifestyle accounts for as many as 14 percent of all colon cancer cases in the United States. People who get lots of exercise have a 30 percent to 40 percent lower risk of developing colon cancer, according to study co-author Elliott Coups, of the Division of Population Science at the Fox Chase Cancer Center in Cheltenham, Pa., and colleagues.

But their analysis of survey data from 1,932 adults who answered questions about colon cancer risk found that only 15 percent said they used physical activity as a way of reducing their colon cancer risk. The findings were published in the August issue of Patient Education and Counseling.

Several factors may contribute to this lack of knowledge about the link between exercise and colon cancer risk.

"Patients may not be learning this information from their health-care providers and information regarding colon cancer prevention is not as well publicized as it could be," Coups said in a new release from the Center for the Advancement of Health.

Doctors may find it easier to tell patients about the general health benefits of exercise, rather than specifically referring to colon cancer, even if a patient has a family history of colon cancer or other risk factors for the disease.

"In the context of busy clinic visits, it is, in some ways, efficient for patients to be reminded that physical activity is good for their health in general. Going through each specific health benefit of physical activity would take considerable time," said Coups.

Sedentary people can greatly benefit from starting a modest exercise program, such as gardening or walking two to three hours a week, according to Dr. Edward Giovannucci, a professor at the Harvard School of Public Health.

"Sedentary people should first set such moderate, achievable goals. More benefits could accrue from higher levels and more intense exercise, such as jogging, running or tennis. To some extent, more may be better, but it is important to note that a little is much better than nothing," Giovannucci said in the news release.

More information

The American Cancer Society has more about colorectal cancer  .

TUESDAY, Aug. 5 (HealthDay News) -- New research with mice suggests that intravenous doses of vitamin C could one day reduce the size of cancerous tumors in people.

The findings are preliminary and still must be confirmed in humans. And even if the treatment works, it's not a cure but would likely be used in combination with other drugs, the researchers said.

Still, the research does show an unexpected use for vitamin C, which has previously been thought of as a nutrient, not a drug, said study co-author Dr. Mark Levine, chief of the U.S. National Institutes of Health's Molecular and Clinical Nutrition Section.

"There's potential promise that [vitamin C] is part of the armamentarium for treating some cancers," he said. "Which ones? We've got to do more and find out."

Vitamin C has long been one of the most respected of all vitamins, lauded for its supposed powers to treat many ills, from colds to heart disease. The late scientist Dr. Linus Pauling increased the vitamin's profile by touting it as a cancer treatment.

But getting heavy doses of vitamin C into the body is a challenge. Unlike some other vitamins, it's virtually impossible for people to overdose on vitamin C since the body only ingests a certain amount through the mouth and then stops allowing it to build up, Levine said. "The body wants to get to a certain place and no more," he said.

Researchers have found that they can disrupt the body's "tight control" over vitamin C levels by giving the nutrient intravenously and bypassing the digestive system, Levine said. The intravenous approach involves "short-circuiting the body's normal control mechanisms and finding there's an unexpected surprise that may be beneficial," he said.

In the new study, published in the Aug. 4-8 issue of the Proceedings of the National Academy of Sciences, Levine and his colleagues found that intravenous vitamin C produced hydrogen peroxide, which proceeded to reduce cancerous tumors in the mice by 43 percent to 51 percent. The mice had ovarian, pancreatic and brain cancer.

It's not clear why some tumors are immune to the treatment and others are not, Levine said, although normal cells are unharmed by the therapy.

According to the researchers, it's possible to intravenously boost levels of vitamin C in humans to the levels used in the mice.

But Levine cautioned that the treatment isn't ready for prime time with humans. "Should patients with any kind of tumor go out and get IV ascorbate [vitamin C]? That's not the message here," he said.

Instead, he said, the study shows the need for more research.

Dr. Len Lichtenfeld, deputy chief medical officer of the American Cancer Society, said the research is interesting but not yet proven.

"Like so many things that are intriguing or appear to be promising, there appears to be a long way to go from the theory in the lab to the practical application in the clinic."

More information

To learn more about vitamin C, visit the U.S. National Institutes of Health.

WEDNESDAY, July 2 (HealthDay News) -- An experimental drug that inhibits tumor blood vessel formation slows the progression of metastatic thyroid cancer in some patients, an international study finds.

Of the 93 patients with rapidly progressing cancer, 49 had a positive response to treatment with motesanib diphosphate. Of those 49 patients, 14 percent had their tumors shrink and 35 had their tumors stabilize for more than 24 weeks. Median progression-free survival was about 40 weeks.

Genetic analysis of 25 patients revealed that drug response was better in those with a mutation known as BRAF V600E in their tumors than in those without the mutation. Further research into this genetic connection is needed, the researchers said.

"Finding that patients whose tumors bear a particular mutation were more likely to respond to the drug is an example of where we would like to head in our research," study author Dr. Steven I. Sherman, chairman and professor of the department of endocrine neoplasia and hormonal disorders at the University of Texas M.D. Anderson Cancer Center, said in a prepared statement.

"This is the first of the various thyroid cancer trials to identify specific mutations that might allow us to individualize or personalize therapy," he said.

The study, published in the July 3 issue of the New England Journal of Medicine, was funded by drug maker Amgen Inc.

Motesanib diphosphate -- a VEGF inhibitor -- targets a protein called vascular endothelial growth factor (VEGF), which plays a critical role in the formation of new blood vessels that allow tumors to grow and spread.

Currently, there are few treatment options for metastatic thyroid cancer.

"There is no standard accepted chemotherapy for advanced metastatic differentiated thyroid cancer, and response rates have typically been 25 percent or less," Sherman said. "Most patients are not treated with systemic chemotherapy, because the limited benefit rarely justifies the side effects. Treatment of thyroid cancer has been a completely unmet need."

More information

The American Cancer Society has more about thyroid cancer  .