Almost 56 percent of patients who underwent the therapy, called stereotactic body radiation therapy (SBRT), were still alive three years after their treatment, according to preliminary findings from a study published in the March 17 issue of the Journal of the American Medical Association, a themed issue on cancer.

By contrast, only about 25 percent to 30 percent of patients who receive conventional fractionated radiotherapy survive that long.

“Stereotactic body radiation therapy controlled peripheral small tumors in a large majority of patients and had an impressive overall survival rate at three years,” said study lead author Dr. Robert Timmerman, professor of radiation oncology at the University of Texas Southwestern Medical Center at Dallas, speaking at a Tuesday teleconference.

Unfortunately, the risk of the cancer spreading to other parts of the body was still high, the researchers noted.

The U.S. National Institutes of Health-funded Radiation Therapy Oncology Group is planning further trials to refine the procedure.

“The study was done by the leading radiation therapy research group in the world but it was very small,” commented Dr. Jay Brooks, chairman of hematology/oncology at Ochsner Health System in Baton Rouge. “It’s provocative but it’s not for all patients with lung cancer. This is for people who can’t undergo surgery, so I think surgery is still the best way to treat early lung cancer,” Brooks said.

“The radiation was effective at controlling the cancer in the spot but the cancer still has a high risk of spreading to other parts of the body,” he added.

Patients who cannot undergo surgery for early-stage lung cancer tend to be frail, with many other medical conditions. They are therefore unable to withstand invasive procedures that would track cancer recurrence, and even the initial biopsy can pose a risk.

Standard treatment right now for these patients is conventional radiation treatment given every weekday for six weeks, or simply observation with supportive care.

In addition to a high mortality rate, only 30 to 40 percent of these patients see their tumors controlled, meaning they don’t grow. Some 8,000 to 10,000 patients in this group are diagnosed each year in the United States, Timmerman said.

“Stereotactic body radiation therapy uses numerous small beams that converge on the target. Each beam is fairly weak [although the overall effect is strong] so there’s not as much entry damage and each beam, being very small, has to be guided very carefully with image guidance,” Timmerman explained.

This study involved 55 patients with inoperable early-stage non-small cell lung cancer, the most common type of lung cancer. Individual tumors were small with most measuring 3 centimeters or less.

Treatment involved 20- to 60-minute sessions one to five times a day or every other day. The entire course of therapy lasted only one-and-a-half to two weeks.

Three years after treatment, almost 98 percent of primary tumors were controlled; local control (the primary tumor and the lobe) was close to 91 percent; and the local-plus-regional control rate was just over 87 percent. This was about double the rate seen with conventional radiotherapy.

Just over 48 percent of participants made it to the three-year mark without a recurrence of their disease.

Disappointingly, 11 patients (22.1 percent) did develop distant metastases, eight of them within two years. The authors speculated that these patients already had metastases that were not detected at the time of diagnosis. But the rate of these recurrences was higher in patients with a certain type of larger tumors, suggesting there may be ways to address this.

Many individuals also had treatment side effects including rib fractures, chest-wall burns, painful swallowing and fluid build-up around the heart.

And the researchers note that many patients continued to smoke throughout and after their treatment.

“There’s definite room for improvement moving forward with therapies,” Timmerman said.

Timmerman reported receiving monies from two companies who manufacture equipment used in SBRT. The study itself, however, was not funded by private interests.

Trauma patients are particularly vulnerable to hospital-acquired infections, Dr. Heather L. Evans of Harborview Medical Center in Seattle, one of the study’s authors, told Reuters Health.

“Many of these patients will go directly to the operating room and maybe not get the best preoperative cleansing, just because the circumstances are such that they need an immediate operation,” she explained.

Researchers had previously shown that bathing medical intensive care unit (ICU) patients with cloths containing the antiseptic chlorhexidine gluconate reduced infections with two types of drug-resistant bacteria, Evans and her team note in their report in the Archives of Surgery.

To investigate whether the cloths would be helpful for trauma ICU patients as well, the researchers used antiseptic-free disposable cloths to bathe these patients daily for six months, and then used the antiseptic cloths for another six months.

Antiseptic bathing cut the likelihood that patients would develop catheter-related bloodstream infections, as well as the risk of ventilator-associated pneumonia caused by methicillin-resistant Staphylococcus aureus (MRSA, popularly known as a “superbug”). Such superbugs kill about 25,000 people a year in Europe and 19,000 in the United States.

Patients who had the antiseptic baths were also significantly less likely to have MRSA or another tough-to-treat bug, Acinetobacter, growing on their bodies, known medically as “colonization.”

Patients in the non-antiseptic group were at nearly triple the risk of having MRSA colonization compared to those who got the antiseptic baths. The only adverse effects that occurred were rashes in two patients.

Evans noted that all ICU patients at Harborview are now being bathed with the chlorhexidine-containing cloths. In 2007, she added, there were 20 cases of MRSA infection per every 1,000 patients admitted; now there are 7.6 for every 1,000 admissions. “That’s pretty impressive,” she said.

Still, the design of the study did not prove the new cloths were responsible for the change, and there is an expense involved: Chlorhexidine cloths cost $5.52 per bath, according to the study, while the regular bath product costs $1.23 per bath. Whether that expense is worth it for thousands of patients per year will require further study, the authors note.

Another potential concern, notes Dr. Shirin Towfigh, of Cedars-Sinai Medical Center, Los Angeles, is that using the chlorhexidine cloths could actually lead to other drug-resistant bacteria. However, Towfigh writes in an accompanying editorial, the study demonstrates important benefits.

SOURCE: Archives of Surgery.

A drug-releasing stent placed in the blocked artery below the knee might re-establish blood flow, new research shows.

Critical limb ischemia, the most severe form of peripheral arterial disease (PAD), causes more than 100,000 leg amputations in the United States each year. Now, researchers from Mount Sinai Medical Center in New York City say insertion of a stent can prevent many of these amputations.

“Traditional balloon angioplasty is plagued by high incidence failure, restenosis [recurrence] and inability to elevate the patient’s symptoms,” said lead researcher Dr. Robert A. Lookstein, associate director of Mount Sinai’s division of interventional radiology.

Patients with critical limb ischemia have leg pain even when resting and sores that don’t heal because of lack of circulation, Lookstein said. They are at risk of gangrene and amputation.

But placing a stent in the affected artery during angioplasty greatly improves these problems, Lookstein added. The drug-eluting stent keeps the narrowed artery open and releases a medication for several weeks after implantation, preventing the artery from closing again, he said.

“Patients with the least severe form of the [severe] disease, those with pain at rest, as well as the patients with minor skin infection of their legs, were able to avoid major amputation,” he said.

But some patients with severe disease and those with gangrene still lost a limb, said Lookstein, who was scheduled to present the finding Monday at the Society of Interventional Radiology’s annual meeting in Tampa, Fla.

For the study, Lookstein’s team followed 53 patients with critical limb ischemia who had a total of 94 drug-eluting stents implanted to treat leg arteries that would not stay open after angioplasty alone. These are the same stents commonly used to open blocked coronary arteries.

The treatment was effective in all the patients, the researchers said.

A year after the procedure, 81.8 percent of the stented arteries were still open, allowing blood to flow freely, the researchers found. And, over an average of 17 months’ follow-up, fewer than 10 percent of the patients required a major amputation, Lookstein noted.

“These results show that when angioplasty doesn’t work, this is an excellent option,” Lookstein said. “Patients should know that if angioplasty fails, there are treatment options that offer excellent outcomes.”

Dr. Juan Pablo Zambrano, an assistant professor of clinical medicine at the University of Miami Miller School of Medicine, said a downside of stent insertion is the need to take blood-thinning drugs for at least a year after surgery.

“The current recommendations for drug-eluting stents require taking antiplatelet drugs for one year,” Zambrano said. This is usually a combination of a drug like Plavix and aspirin, he said.

Not taking them greatly increases the chances of clotting in the stent, which can cause a thrombosis (a blood clot), and the likelihood that a clot will break loose and travel to the heart or lungs, Zambrano said.

“If you leave these patients without treatment, you get very early amputations,” he said. “If you can change the fate of the disease by stenting those vessels and keeping them open for longer, then you are going to have a significant impact,” he said.

About 10 million Americans suffer from peripheral arterial disease, but only one in four is diagnosed and treated, according to background information with the study. The condition results from plaque build-up, which hardens in the arteries, blocking and reducing blood flow to the legs, arms, brain and other organs.

Bypass surgery, the standard treatment to open an artery, isn’t an option for many patients because of other medical problems, Lookstein said. He said their results show that stent insertion is as effective as bypass surgery.

The alternative is angioplasty, which involves threading a catheter through the artery and inflating a balloon at the tip of the catheter to open the vessel. But arteries below the knee often close up again after angioplasty.

Those patients would be candidates for a stent in the artery, Lookstein said.

This suggestion, released Wednesday in a U.S. National Institutes of Health draft consensus statement, could pave the way for more people to eat more dairy products, thus helping to ensure they get adequate nutrition in their diet.

Not enough data is available to estimate the prevalence of true lactose intolerance in the United States, the report stated, but it’s likely the numbers are lower than those reported, said Natalie J. Miller, a member of the panel that issued the draft statement and a graduate student at the University of Pennsylvania School of Veterinary Medicine, at a Wednesday teleconference.

People with lactose intolerance usually are told to avoid milk and milk-containing products, but this can deprive them of needed nutrients, particularly calcium and vitamin D.

“Particularly in children and adolescents, it’s very difficult for them to receive enough calcium and vitamin D if they avoid diary completely. The same thing may hold true for adults,” said Dr. Frederick J. Suchy, chairman of the conference preceding the statement and professor and chief of pediatric hepatology at Mount Sinai School of Medicine in New York City.

“Vitamin D and calcium have important effects, for certain for bone health, and may have implications in other areas such as cardiovascular health, hypertension and maybe even colon cancer,” he said.

Lactose is a sugar found in both human and cow’s milk.

“In order to be absorbed as a nutrient, lactose has to be digested by lactase, an enzyme present in the lining of the small intestine,” Suchy explained. “It’s well recognized that during the period of suckling in the infant, levels of lactase in the intestine are at their highest in order to be able to digest and absorb an important food source.”

By age of 3 or 4, however, lactase production usually decreases, and most people become “lactase nonpersisters.”

“The majority of the world’s population, after weaning and gradually over childhood, lose lactose activity,” Suchy said. “It’s a normal state. Only those people that are largely from northern European descent have retained lactase and have the ability to ingest and process lactose later in life.”

But even most “nonpersisters” aren’t really intolerant to lactose and could consume more dairy products.

It’s first important to distinguish whether symptoms attributed to lactose intolerance — diarrhea, abdominal pain, bloating and flatulence — result from another, potentially serious gastrointestinal condition, such as irritable bowel syndrome or celiac disease.

But, said Suchy, even “if it is a problem with lactose, there may be strategies to cope with that.”

Right now, when lactose intolerance is suspected, “the reflex response oftentimes is to tell the patient to stop taking dairy products completely,” Suchy said. “There may be some patients where that has to be done and whatever nutritional deficiencies could be made up with supplements.”

But for others, alternative strategies like taking small amounts of milk throughout the day or with meals or including yogurt and hard cheeses, especially low-fat hard cheeses, in the diet might be tolerable.

“This is not an allergic condition where if you take a little bit of milk you get sick. That’s quite rare,” noted Dr. Marshall A. Wolf, a panel member and professor of medicine at Harvard Medical School in Boston. “This is a quantitative condition and most people, even those with malabsorption, can take a certain amount of milk products without any symptoms, and there is some evidence to suggest that if you take milk products on a regular basis, you can build up your tolerance for milk.”

SOURCES: teleconference with Frederick J. Suchy, M.D., panel and conference chairperson, and professor and chief of pediatric hepatology, Herbert H. Lehman Professor and Chair, Department of Pediatrics and Pediatrician-in-Chief, Mount Sinai School of Medicine; Natalie J. Miller, graduate student, School of Veterinary Medicine, University of Pennsylvania, Philadelphia; Marshall A. Wolf, M.D., professor, medicine, Harvard Medical School and Brigham and Women’s Hospital, Boston; U.S. National Institutes of Health Consensus Development Conference: Lactose Intolerance in Health draft consensus

The problem was more pronounced among men 20 to 29 years of age, 35 percent of whom went without coverage for medical care. As a result, these uninsured 20-somethings are less likely to visit a doctor on a regular basis, less likely to fill prescriptions and more likely to arrive at the emergency room.

“The highest uninsured rate is among people in their 20s and even though this is a relatively healthy group, they do need some access to health care,” said Robin A. Cohen, lead author of a data brief just released by the National Center for Health Statistics, part of the U.S. Centers for Disease Control and Prevention.

“If you don’t have insurance you’re less likely to have a usual source of medical care. You’re also less likely to have visited a doctor and you’re more likely to have an unmet medical need,” Cohen added.

“This is a problem that’s existed for some time, and it’s worsened over the last few years,” said Sara Collins, vice president of the Affordable Health Insurance Program at The Commonwealth Fund in New York City. “We have an employer-based health insurance system so to the extent that you are without strong connections to that system when you have a transitional period, you’re going to be at risk of losing your health insurance coverage.”

And people in their 20s generally are in transition, moving from home where they could be on their parents’ plan, to college where they could be on a college plan or to the workforce, where they may be on no plan.

And children who had been covered under Medicaid aren’t likely to be eligible for that program when they turn 19, Collins added.

Based on data collected from more than 13,000 adults aged 20 to 29, the researchers discovered that:
U.S. adults in their 20s were almost twice as likely as adults aged 30 to 64 to go without health coverage (31 percent versus 17 percent).
Seventy percent of adults in their 20s had a “usual source” of medical care, although only 44 percent of young adults without insurance had such a source.
Women were more likely to have regular health-care practitioners than young men: 91 percent of women among those with private coverage versus 70 percent of men in the same category. Fifty percent of women without coverage had a regular doctor, compared with 39 percent of men in this category.
Adults in this age group without insurance were four times as likely as those with private insurance and twice as likely as those with Medicaid to have “unmet medical need.”
One-quarter of uninsured people in this age group did not fill a needed prescription, compared with 6 percent of those with private insurance and 12 percent of those on Medicaid. Women were more likely than men to have an unmet need in this area.
About 10 percent of adults in their 20s reported at least two visits to an emergency room in the past year, with women twice as likely to have visited compared with men (12 percent versus 6 percent).

Greg Scandlen, founder of Consumers for Health Care Choices, pointed out that the situation has probably worsened since 2008 as a result of the deteriorating economy, but that there was little new in the idea that many 20-somethings lack health insurance.

“It’s always been young adults who are most likely to be uninsured, and most of the people who are employed do have workers’ comp and do have auto insurance so they are actually covered for things most likely to happen to them in that age group,” he said.

“The implication here is that everyone should see a doctor once a year. I think that’s crazy. The whole notion of an annual physical exam is just a waste of money,” Scandlen said. “Women are far more likely to see a doctor more regularly because of ob/gyn issues, but the fact that young men in their 20s don’t see a doctor doesn’t bother me at all.”

SOURCES: Robin A. Cohen, Ph.D., statistician, National Center for Health Statistics, Division of Health Interview Statistics, U.S. Centers for Disease Control and Prevention; Greg Scandlen, founder, Consumers for Health Care Choices; Sara Collins, vice president, Affordable Health Insurance Program, The Commonwealth Fund, New York City; Access to and Utilization of Medical Care for Young Adults Aged 20-29 Years: United States

The guidelines, which stem from a review of available research on drug treatments for cerebral palsy, also said that botulinum toxin type A, nicknamed Botox, is generally safe but does pose some risk.

“In reviewing this drug for treatment of spasticity in children, the [U.S.] Food and Drug Administration is investigating isolated cases of generalized weakness following use of botulinum toxin type A for spasticity,” Dr. Mauricio R. Delgado, of the University of Texas Southwestern Medical Center in Dallas and lead author of the guidelines, said in a news release from the academy.

The guidelines also recommend consideration of the drug diazepam for short-term treatment of spasticity, although generalized side effects have been linked to its use. Another drug, tizanidine, might also be considered but carries a risk of liver toxicity, according to the guidelines.

Delgado and his colleagues also looked at several other drug treatments but concluded there wasn’t enough evidence to make a recommendation.

“There is an urgent need for more research to establish the effectiveness of the current treatments for generalized spasticity and to find additional, safer and more effective medications,” Delgado said.

Most children with cerebral palsy have spasticity. Although the disease cannot be cured, treating its effects has been shown to improve a child’s capabilities.

The guidelines are published in the issue of Neurology.

Men who consistently failed to express their resentment over conflicts with a fellow worker or supervisor were more than twice as likely to have a heart attack or die of heart disease as those who vented their anger, claims a report in the Nov. 24 online edition of the Journal of Epidemiology and Community Health.

In fact, ignoring an ongoing work-related conflict was associated with a tripled risk of heart attack or coronary death, the study of almost 2,800 Swedish working men found.

“It is not good just to walk away after having such a conflict or to swallow one’s feelings,” said study co-author Constanze Leineweber, a psychologist at Stockholm University’s Stress Research Institute.

The study did not specify good ways of coping with work-related stress — “We just looked at the bad side of coping,” Leineweber explained.

The study doesn’t advocate being belligerent at work, Leineweber cautioned. “Shouting out, and so on, is not proper coping,” she said.

But venting one’s anger outside of the workplace didn’t seem to take a cardiovascular toll, at least. “Getting into a bad temper at home” was not associated with an increased risk of heart attack or cardiac death, the study authors found.

The findings echo those from a study published last year in the journal Occupational and Environmental Medicine. That study, also from Sweden and involving more than 3,100 men, found that having an overbearing or incompetent boss boosted workers’ odds for angina, heart attack and death.

Leineweber stressed that what is true for men might not be true for female workers. While the study included more than 2,000 women, too few of them had heart attacks or died of heart disease to allow conclusions to be drawn.

“Earlier studies have indicated that women use different coping strategies than men,” Leinewaber said. “So for women, strategies such as going away and not saying anything might not be good.”

Women in general appear to handle stressful situations better than men, noted Dr. Bruce S. Rabin, director of the Healthy Lifestyle Program at the University of Pittsburgh Medical Center.

“Social interaction, having people to talk to, is extremely important,” Rabin said. “If you keep things to yourself, you have high levels of stress hormones. Women are more comfortable in social interactions than men. They talk more, while men tend to keep within themselves.”

A study, conducted by the Swedish researchers in 2005, found that women did not have the same levels of cardiovascular risk factors as men, Rabin noted.

There is no one key to handling on-the-job stress, because the level of stress depends on an individual’s environment, at work and in the home, he said.

“Work environment is important,” Rabin said. “You need interaction between people so that everybody feels they can express their opinions about their work. You shouldn’t come to work with a feeling that no one cares.”

“And when you go home, it is very important to share your feelings with whomever you are sharing with,” Rabin added. “Also, you should understand that children learn from the behavior of parents. You can have a meaningful effect on the long-term health of children by being good role models. The message is that the environment you culture can affect not only your health but also the health of those who are important to you.”

The study from the Massachusetts General Hospital Cancer Center in Boston found that survival and tumor response in patients treated with bevacizumab (Avastin), an angiogenesis inhibitor that has helped slow the growth of other cancers, in addition to the chemotherapy regimen of gemcitabine and oxaliplatin — a combined treatment called GEMOX-B — was comparable to findings in previous studies in which patients were treated with gemcitabine and oxaliplatin alone.

In the new phase 2 trial, 35 biliary-tract cancer patients were given all three drugs intravenously (bevacizumab at 10 milligrams per kilogram, followed by gemcitabine at 1,000 milligrams per square meter, and oxaliplatin at 85 milligrams per square meter) on days 1 and 15, every 28 days. Whole-body PET scans were used to assess patients at the start of the study and at the end of the second cycle of treatment.

The researchers found that the overall tumor response rate was 40 percent (14 patients with confirmed partial responses) and stable disease was noted in another 10 patients (29 percent). The overall survival was found to be 12.7 months, with a median progression-free survival of seven months. However, progression-free survival at six months was below the targeted rate at 63 percent, they noted.

The most common negative side effects of GEMOX-B therapy were fatigue, an abnormally low number of white blood cells, peripheral neuropathy, high blood pressure and gastrointestinal problems, but the therapy was generally well-tolerated, the study authors pointed out.

The findings add to increasing evidence “supporting the combination of molecularly targeted agents with chemotherapy to further improve treatment outcomes in patients with biliary-tract cancers,” the researchers wrote.

The National Institute on Aging (NIA), part of the National Institutes of Health, today announced the start of a large-scale clinical trial to evaluate the effect of testosterone therapy on older men. Led by the University of Pennsylvania School of Medicine and conducted at 12 sites across the nation, the Testosterone Trial will involve 800 men age 65 and older with low testosterone levels.

“We know that, as men get older, a significant proportion are unable to carry out activities of daily living and experience decreased physical and cognitive function and decreased independence,” said NIA Director Richard J. Hodes, M.D. “We do not know the extent to which low levels of testosterone may contribute to these conditions.”

A 2004 report by the Institute of Medicine, “Testosterone and Aging: Clinical Research Directions,” noted several important unanswered questions about the effects of testosterone therapy. The NIA is aiming to answer these questions by testing the effectiveness of testosterone therapy in older men with low testosterone levels and one of the following conditions: impaired walking, low vitality, sexual or cognitive dysfunction. A key consideration is the use of testosterone as a therapy for certain conditions, rather than as a preventive measure.

The NIA is the primary source of support for this trial. Additional funding is being provided by the National Heart, Lung, and Blood Institute (NHLBI); the National Institute on Neurological Disorders and Stroke (NINDS); the Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD) and Solvay Pharmaceuticals, which is also supplying the study drug.

The Testosterone Trial will include five separate studies. At each of the 12 sites, men 65 and older with low serum testosterone and at least one of the following conditions — anemia, decreased physical function, low vitality, impaired cognition or reduced sexual function — will be randomly assigned to participate in a treatment group or a control group. Treatment groups will be given a testosterone gel that is applied to the torso, abdomen, or upper arms; control groups will receive a placebo gel. Serum testosterone will be measured monthly for the first three months and quarterly thereafter up to one year. Participants will be tested on a wide range of measures to evaluate physical function, vitality, cognition, cardiovascular disease, and sexual function.

“This study is important because testosterone products have been marketed for many years as treatments for a variety of conditions,” said Evan C. Hadley, M.D., director of NIA’s Division of Geriatrics and Clinical Gerontology, which is the primary funder of the trial. “”We hope this trial will establish whether testosterone therapy results in clear benefits for older men.”

The University of Pennsylvania School of Medicine is the lead institution for the trial and will serve as coordinating center for the study sites. Peter J. Snyder, M.D., professor of medicine in the Division of Endocrinology, Diabetes and Metabolism at Penn, is the principal investigator and will oversee trial activities. “This is an unprecedented opportunity for older men to learn more about themselves and at the same time help find out if testosterone will improve some of the afflictions of old age,” said Dr. Snyder.

Recruitment of study participants will begin in November of 2009. Men age 65 and older who are interested in participating should call the site closest to them. Men living within a 50-mile radius of the study centers, listed below, are especially encouraged to participate.

Participating institutions and their phone numbers include:
University of California, Los Angeles; 310-222-5297
University of California, San Diego; 877-219-6610
Boston University; 617-414-2968
University of Pittsburgh; 800-872-3653
Albert Einstein College of Medicine, Bronx, N.Y.; 718-405-8271
Baylor College of Medicine, Houston, Texas; 713-798-8343
University of Minnesota, Minneapolis; 612-625-4449
Yale University, New Haven, Conn.; 203-737-5672
University of Alabama at Birmingham; 205-934-2294
VA Puget Sound Health Care System and University of Washington School of Medicine, Seattle; 206-768-5408
Northwestern University, Evanston, Ill.; 877-300-3065
University of Florida, Gainesville; 866-386-7730, 352-273-5919

Social isolation can actually change the expression of genes important in the growth of mammary gland tumors, according to Dr. Suzanne D. Conzen, an associate professor of medicine at the University of Chicago and the study’s lead author.

“As far as we know, this is the first assessment of gene expression in mammary glands, looking at the molecular basis for differences in tumor development under the setting of social stress,” Conzen said at a news conference Tuesday.

The findings, published in the October issue of Cancer Prevention Research, follow other studies, some in humans, that showed stress can adversely impact cancer. One study, for instance, found that stressful marriages are bad for breast cancer recovery.

Conzen and her colleagues randomly assigned mice that were genetically susceptible to breast cancer to live either in isolation or in group housing.

“We separated the mice at a very young age, just a few days after they had been weaned from their mothers’ milk,” Conzen said. “Mice are social animals. In the wild, they live in groups of three or four. They have dramatic responses to isolation.”

“What we found was the isolated mice developed larger and more breast cancers than the group-housed mice,” she added.

Three and a half weeks into the isolation, Conzen’s team measured gene expression in the animals’ mammary glands, the equivalent of the human breast. “We found very reproducible changes in gene expression [in the isolated mice]. We found genes that were turned on and turned off that had to do with metabolism,” she said. These pathways are known to contribute to increased growth of breast cancer, she added.

The isolated mice also had a higher corticosterone stress hormone response than did the group-housed mice.

The changes in the expression levels of metabolic pathway genes occurred in the isolated mice even before the tumor size differences were able to be measured, Conzen said.

So what are the practical applications of the research?

The findings may suggest molecular biomarkers, or targets, for preventive intervention in breast cancer, she said.

“Many questions remain,” Conzen added. “One of the things we did note is that the isolated animals were much more vigilant, less exploratory. They released more of a stress hormone when we added another stressor to the situation [besides the isolation].”

Thea Tisty, a pathology professor at the University of California, San Francisco, who is familiar with the findings, called the research “a very exciting beginning.”

The implication is that perceived or actual stress from outside can affect which genes get turned on or off. If the research findings bear out, it could lead to a way to catch tumors in their formation before they become tumors and suppress them, she said.

Another expert speaking at the briefing cautioned that the findings, while exciting, are only preliminary and based only on animal studies.

“This is an area that has a long way to go in terms of understanding how these factors play out in humans,” said Caryn Lerman, the Mary W. Calkins Professor of Psychiatry at the Abramson Cancer Center at the University of Pennsylvania in Philadelphia.