In their study, researchers from the University of Michigan Comprehensive Cancer Center looked at 2,582 white patients and 134 black patients, aged 66 and older.

The study found that 75 percent of whites and 73 percent of blacks saw an oncologist after being diagnosed with rectal cancer, but only 54 percent of blacks received chemotherapy, compared with 70 percent of whites. In addition, rates of referral to a radiation oncologist were similar, but only 74 percent of blacks received radiation therapy, compared with 83 percent of whites.

The findings were published in the May 13 online issue of the Journal of the National Cancer Institute.

"Although there wasn't a discrepancy between African-Americans and whites in the rates of consultation with an oncologist, we found a large discrepancy in the receipt of chemotherapy. This is very important. We knew that African-Americans were not receiving chemotherapy for rectal cancer at the same rates as white Americans, and it was contributing to their increased mortality. Now we have a better idea of where the problem lies: somewhere between the visit with the oncologist and the actual initiation of chemotherapy," study author Dr. Arden Morris, an assistant professor of surgery at the U-M Medical School and chief of general surgery at the VA Ann Arbor Healthcare System, said in a prepared statement.

Compared to whites, blacks have as much as a 20 percent worse long-term survival rate after rectal cancer surgery. It's known that the use of chemotherapy and radiation improves survival in all rectal cancer patients by as much as 20 percent. It's believed that the lack of chemotherapy and radiation treatment in blacks is largely responsible for their lower long-term survival rates.

"We now know that the initial visit with an oncologist is not the barrier to treatment. Our next step is to better understand what are the human factors that contribute to this discrepancy. We're interested in hearing what individual people have to say," Morris said.

She and her colleagues suspect social differences and priorities among different groups -- such as patient preferences or access to resources such as transportation or family care -- may contribute to these discrepancies.

"Choice is important. If there's a choice, this maybe isn't a disparity but a preference. But if it's not a choice, then we need to understand the barriers and find solutions," Morris said.

In her next study, she plans to interview patients who've been treated for colorectal cancer to learn how they reached the decision to have chemotherapy or whether they feel they even made that decision themselves.

More information

The U.S. National Cancer Institute has more about colorectal cancer.

The bad news is a risk factor you can't change: Women whose sisters were diagnosed with breast cancer face an increased risk of breast cancer throughout their lives, regardless of their sister's age at diagnosis, according to a study in the May 13 issue of the Journal of the National Cancer Institute (JNCI).

The good news comes from a risk factor you can do something about: Women who exercise are much less likely to develop breast cancer, according to two new research studies -- one from the same issue of JNCI, and the other from the 2008 online first edition of the British Journal of Sports Medicine.

The first study from JNCI compared the rate of breast cancer in nearly 24,000 sisters of women with breast cancer to the rate of cancer in nearly 1.8 million women with sisters who didn't have breast cancer. All of the women were from Sweden, and the data collection for the study spanned from 1958 to 2001.

The researchers found that women between the ages of 20 and 39 who had a sister who'd been diagnosed with breast cancer faced a sixfold higher risk of breast cancer than did women whose sisters didn't have breast cancer. The excess risk declined as the women aged but didn't disappear. Women who were older than 50 with a sister with breast cancer had about a twofold risk of developing the disease, according to the study. And, it didn't matter what age the sister was when she was diagnosed.

"After the diagnosis of breast cancer in a family, the other sisters -- especially the youngest -- have an increased risk of breast cancer that persists for 20 years," said one of the study's authors, Marie Reilly, a professor of biostatistics at the Karolinska Institute in Stockholm, Sweden. "This suggests that sisters of breast cancer patients, especially the young sisters, should be intensely screened, independent of the screening recommendations for women their age."

Dr. Julia Smith, director of the Lynne Cohen Breast Cancer Preventative Care Program at the New York University Cancer Institute and Bellevue Hospital in New York City, called the findings "interesting and troubling." She added, "Sisters have to worry about increased risk no matter when their sister was diagnosed."

The second study from JNCI relied on data from the Nurse's Health Study II and included information from almost 65,000 women who completed questionnaires about their physical activity from age 12 until age 35. During the six-year follow-up period, 550 women from that group were diagnosed with breast cancer.

Women who walked about 13 hours a week or ran 3.25 hours a week had a 23 percent reduced risk of developing premenopausal breast cancer than women who were less active. The incidence rates of breast cancer were 194 per 100,000 "person-years" for the least active women, compared to 136 cases per 100,000 "person-years" for the most active women.

"These results suggest that consistent physical activity during a woman's lifetime is associated with decreased breast cancer risk. Unlike many risk factors for breast cancer, physical activity is an exposure that can be modified," wrote the study's authors, who were led by Dr. Graham Colditz, of Washington University School of Medicine in St. Louis.

Smith said: "For many reasons, women should continue to exercise and try to be in shape." It makes sense that exercise might reduce breast cancer risk, she said, adding, "Women who are exercising regularly are decreasing body fat and estrogen."

The third study on breast cancer risk was an analysis of 62 other studies that looked at the impact of physical activity and breast cancer risk. This review, published online ahead of the print version of the British Journal of Sports Medicine, found that women who are physically active have a 25 percent decreased risk of breast cancer.

The researchers found that both recreational or on-the-job activity could reduce risk, and that moderate and vigorous exercise caused a similar reduction in risk. This review also found that activity performed after menopause was more effective in reducing risk.

Smith recommends that women exercise at least 20 minutes, three times a week, and preferably more. She said that during those 20 minutes of moderate to vigorous exercise, the heart rate should consistently be above baseline.

More information

To learn more about breast cancer risk factors, visit the American Cancer Society.

But, the study authors noted, ultrasound also significantly increases the rate of false-positive readings.

"In our study participants, half of the breast cancers were found using mammography alone. By adding ultrasound, we found 78 percent of the cancers," said the study's lead author, Dr. Wendie Berg, a radiologist at an outpatient center in Lutherville, Md., affiliated with Johns Hopkins Medical Center.

However, identifying those extra cancers came with a cost of significantly more false-positive readings.

"With mammography, a woman has about a one in 40 chance that a biopsy will turn out not to be cancer. With the addition of ultrasound, it's one in 10," Berg said.

Results of the study, which was funded by the Avon Foundation and the U.S. National Cancer Institute, were published in the May 14 issue of the Journal of the American Medical Association.

Each year, more than 180,000 American women are diagnosed with breast cancer, and almost 41,000 will lose their lives to the disease. Death rates from breast cancer have been declining, possible due to earlier detection and diagnosis, according to the American Cancer Society.

The new study included almost 3,000 women recruited from 21 centers. The average age was 55 years old, and all of the women had a higher-than-normal risk of breast cancer.

The women were randomly assigned to receive either mammography alone or mammography plus ultrasound performed by a physician.

Forty women were diagnosed with breast cancer within a year of their initial screening. Mammography alone uncovered 20 cancers, 50 percent, while the combination screening technique found 31 of the cancers, or about 78 percent, according to the study.

That means for every woman screened, mammography alone will find 7.6 cancers, mammography plus ultrasound will detect 11.8 cancers, and three cancers will be missed altogether, the researchers said.

The study found that ultrasound was a good complementary screening tool for mammography, because it found cancers that mammography might miss.

"Ultrasound performs best in cases for which mammography performs weakest, i.e., in breast areas with dense fibroglandular tissue," Dr. Christiane Kuhl, with the Department of Radiology at the University of Bonn in Germany, wrote in an accompanying editorial in the journal. Kuhl also noted that the drawbacks to ultrasound include the frequency of false-positives, the cost of the test, and a lack of evidence that the test affects mortality.

Berg noted that there aren't currently enough physicians or ultrasound technicians trained for ultrasound to be a viable, widely used screening tool right now, even just for high-risk women.

"On average, physicians can only perform three to five ultrasounds per hour," said Berg, compared to as many as 50 mammograms in an hour, according to the editorial.

Dr. Julia Smith, director of the Lynne Cohen Breast Cancer Preventative Care Program at the New York University Cancer Institute and Bellevue Hospital in New York City, said, "I already do ultrasounds on women at risk. As a complementary test, ultrasound can be a very useful test. Also, we know it's relatively inexpensive and safe."

Magnetic resonance imaging (MRI) may be more effective than either mammography or ultrasound, and it's fast becoming a popular tool for breast cancer screening, but, Smith said, the cost of MRI is prohibitive.

Given limited health-care resources, Kuhl wrote that "mammography will probably remain the basis for breast cancer screening for the foreseeable future."

Smith said what's most important is for women to talk with their doctors about their individual risk of breast cancer, and then decide which screening tests would be most appropriate.

More information

To learn more about breast cancer screening options and current recommendations for screening, visit the American Cancer Society.

Positron emission tomography with a radioactive tracer (18F-FDG PET) is one of three imaging techniques commonly used to check whether head and neck squamous cell cancer has spread to the nearby lymph nodes in such patients. This is important in determining the prognosis of the disease, since some patients who clinically appear free of these types of metastases may actually have small tumors within their lymph nodes.

The findings are based on an analysis of 32 previously published studies done on head and neck cancer patients with one or fewer nodal metastases. The team from the University of Ioannina School of Medicine, in Greece, found that FDG-PET failed to identify half the lesions in patients whose lymph nodes tested negative.

The analysis, published online May 13 in the Journal of the National Cancer Institute, also found that the imaging technique incorrectly identified normal tissue as being cancerous 13 percent of the time.

The sensitivity and accuracy of FDG-PET compared with the two other common imaging techniques used -- magnetic resonance imaging (MRI) and computed tomography (CT) -- appears to be slightly better, but researchers said the differences were not statistically significant. The rate of false positives for each of the three imaging techniques was similar.

"Thus, there is little evidence to support the routine use of 18F-FDG-PET to evaluate possible lymph node metastasis among patients with [head and neck squamous cell cancer] and a clinically negative neck," the authors wrote.

An accompanying editorial in the journal notes that clinicians typically use multiple imaging techniques and clinical examinations rather than a single test to compose a full picture of their patients condition and disease.

"Prospective data remain a critical necessity to translate imaging improvements with FDG-PET into proven treatment improvements," the editorialists wrote.

More information

The U.S. National Cancer Institute has more about head and neck cancers.

About 16 percent of the 74 breast cancer patients studied by researchers at the Ohio State University Medical experienced PTSD 18 months after their cancer diagnosis. These same patients were three times more likely to have had anxiety disorders.

"What is unique about breast cancer patients with PTSD is that they have already had this double hit of both anxiety and mood disorders even before they got the diagnosis," study co-author Barbara Andersen, a professor of psychology at Ohio State University, said in a prepared statement. "So when they are in a new situation that is very anxiety-provoking -- cancer diagnosis and treatment -- it is not surprising that they are at risk for developing PTSD."

While the study suggests most cancer patients aren't at risk for post-traumatic stress disorder, Andersen said mood disorders are a concern.

"I think depression is the mental health condition that needs the most attention as far as treating breast cancer patients, even more so than PTSD," she said. "That's the direction our research is going, and we are working to develop an intervention to treat cancer patients with depression."

She said the findings, published in the April issue of the Journal of Traumatic Stress, suggest screening newly diagnosed breast cancer patients for past mood disorders might help avoid their developing post-traumatic stress disorder.

Another 20 percent of those in the study had "subsyndromal" post-traumatic stress disorder, a condition in which they experienced significant symptoms of PTSD but not at the level of those with the full diagnosis.

About one-third of women with PTSD also had past problems with alcohol/substance abuse or dependence, compared to one-fifth of subsyndromal women and one-tenth of women with no PTSD.

Also, patients who developed PTSD tended to have a history of traumatic life events, the study reported. Half of the PTSD patients reported being physically attacked or abused previously, compared with less than 17 percent of the other women.

More information

The U.S. National Institute of Mental Health has more about post-traumatic stress disorder.