October 31, 2007, 8:05 PM CT

New genetic variant for prostate cancer

Two tiny genetic variations may provide the best clues yet for finding more precise ways to estimate prostate cancer risk and improve screening and early detection for men of African descent, report scientists from the University of Chicago and the Translational Genomics Research Institute, Phoenix, AZ, in the December 2007 issue of Genome Research, published early online.

The scientists set out to determine whether results from four prior studies that linked genetic variations on one region of chromosome 8 to increased prostate cancer risk among Caucasians were also valid for men of African heritage. In the process, however, they found an additional genetic variation among African American men that was an even stronger marker for cancer risk for these men. That variation is located within a gene that plays a role in DNA repair. A malfunction in DNA repair could contribute to cancer development.

"This finding emphasizes the importance of ancestry in studying genetics," said study author Rick Kittles, associate professor of medicine at the University of Chicago Medical Center. "Prior studies led us to one specific region of chromosome 8," he said. "Then this approach -- which took advantage of genetic differences among African American men, who are at very high risk for this type of cancer -- led us to a different locus within that region and directly to a gene of interest......... Posted by: Jessica      Read more         Source

October 29, 2007, 10:34 PM CT

Preventing blood clots in cancer patients

An international panel of scientists led by an oncologist from the Duke Comprehensive Cancer Center has put together a set of guidelines for the prevention and therapy of dangerous blood clots that threaten cancer patients.

"Cancer patients are at increased risk for what is known as venous thromboembolism -- or the formation of a blood clot -- which can be deadly," said Gary Lyman, M.D., director of the Health Services and Outcomes Research Program in Oncology at Duke and co-chair of ASCOs Venous Thromboembolism Expert Panel. "These new guidelines will give clinicians some of the tools they need to prevent and treat this dangerous complication of cancer".

The guidelines, which are based on studies that have been published in the medical literature, would be reported in the December 1, 2007 issue of the Journal of Clinical Oncology. They will also appear early online on the American Society of Clinical Oncology Web site on October 29, 2007.

It is estimated that venous thromboembolism (VTE) affects four to 20 percent of cancer patients, and is one of the leading causes of death in this population, Lyman said.

"We have long known that there is an association between cancer and risk for VTE, and we can speculate what some of the reasons for this link might be," he said. "Tumor cells may release proteins that encourage clotting, and these patients are often bedridden and immobile, which also puts them at increased risk"......... Posted by: Jessica      Read more         Source

October 29, 2007, 10:26 PM CT

Breast cancer returns more often in black women

Contrary to prior studies, African-American women with early-stage breast cancer who have surgery to remove the cancer (lumpectomy) followed by radiation treatment have a higher chance of their cancer coming back in the breast and lymph nodes 10 years after diagnosis, in comparison to their Caucasian counterparts, as per the largest study of its kind, presented at a scientific session October 29, 2007, at the American Society for Therapeutic Radiology and Oncologys 49th Annual Meeting in Los Angeles.

The study also shows that early-stage patients with breast cancer who are African-American women who are diagnosed with the disease at a younger age have a higher disease stage at diagnosis (larger tumors and cancer that has spread to the lymph nodes) and more aggressive tumors than Caucasian women who undergo similar therapy.

This study confirms the aggressive nature of breast cancer in African-American women and emphasizes how important it is for all African-American women to see their healthcare providers regularly and to go for screening mammograms to try to catch any abnormalities early, said Meena S. Moran, M.D., the lead author of the study and a radiation oncologist at the Yale University School of Medicine in New Haven, Conn. This study also points out the need for further research in evaluating the underlying molecular, genetic and biological differences in breast cancers in African-American women so that we can develop better strategies for helping these women beat their cancer......... Posted by: Jessica      Read more         Source

October 29, 2007, 9:46 PM CT

One Step Closer To Cancer Vaccine

When cells become malignant, the sugars on their surfaces undergo distinct changes that set them apart from healthy cells. For decades, researchers have tried to exploit these differences by training the immune system to attack malignant cells before they can spread and ravage the body.

Now, scientists at the University of Georgia Cancer Center have synthesized a carbohydrate-based vaccine that - in mice - has successfully triggered a strong immune response to cancer cells. The finding, reported in the recent issue of the journal Nature Chemical Biology, brings the researchers one step closer to a much-sought-after "cancer vaccine".

"In mice we can illicit very strong antibody responses and we have shown that the antibody responses are functional - that they can kill cancer cells," said lead author Geert-Jan Boons, Franklin professor of chemistry.

Vaccines are currently used to prevent diseases by priming the immune system to recognize and attack a virus or bacteria. The vaccine that Boons and his team have developed, conversely, is a therapeutic vaccine that trains the body's immune system to fight an existing disease.

The discovery in the 1970s of unique sugars on cancer cells set researchers in search of a way to get the immune system to recognize and attack cells that express these cancer-associated sugars. Until now, however, the results have been less than spectacular......... Posted by: Jessica      Read more         Source

October 28, 2007, 2:04 PM CT

Patient navigators help low-income cancer patients

Volunteers who guide low-income and minority cancer patients through cancer treatment, called lay patient navigators (LPN), help them to overcome major obstacles that prevent them from receiving quality care and achieving better outcomes, according to a study presented October 28, 2007, at the American Society for Therapeutic Radiology and Oncologys 49th Annual Meeting in Los Angeles.

Minority and low-income cancer patients continue to receive inferior care in the detection and treatment of cancer, compared to the general population. They are also under-represented in cancer clinical trials, which can potentially save or extend the lives of trial participants, especially those who have few treatment options.

To better understand how LPNs can help these at-risk patients, researchers studied nearly 500 African American and Latino cancer patients with mean family incomes below the poverty level. Almost two-thirds (60 percent) of patients studied accepted help from LPNs to overcome their barriers to getting cancer treatment. Results show that the time it took to reduce these barriers decreased from an average of 42 days to only one day. The study also showed that LPNs offered patients more access to participation in cancer clinical trials.

The study was conducted by the Urban Latino African American Cancer Disparities Project to identify and confront the root causes of treatment disparities in underserved communities and offer better access to clinical trials. It was supported by a grant from the National Cancer Institutes Cancer Disparity Research Program......... Posted by: Jessica      Read more         Source

October 28, 2007, 2:00 PM CT

Positioning pelvic cancer patients on stomachs

Oregon Health & Science University Cancer Institute scientists have observed that positioning pelvic cancer patients on their stomachs rather than their backs is a better method for delivering radiation treatment. Because patients return for multiple therapies, being able to reproduce.

the positioning of the patient allowed more precision, which reduces toxicity.

It was a surprising finding, as per as per Martin Fuss, M.D., the director of the Program in Image-Guided Radiation Therapy, OHSU Radiation Medicine, and OHSU Cancer Institute member.

This finding runs contrary to the common perception that the supine (on the back) position is more stable, convenient and therefore caused less variation in day-to-day setups. Variation in setups require the use of margins that extend beyond the tumor into normal tissues, exposing organs with limited tolerance to radiation to a higher risk for therapy-induced toxicity, said Fuss, who is also a professor in the OHSU School of Medicine.

A poster presentation from this study will be presented Sunday, Oct. 28 at the 2007 American Society of Therapeutic Radiology and Oncology (ASTRO) meeting in Los Angeles.

Having a patient lay on his belly, or prone position, has been considered to be uncomfortable and can lead to more patient movement, which can cause more damage to healthy cells that need to be spared from high-dose radiation. But through this study it was observed that lying on the stomach, using a belly board, with a hole cut out for the stomach area, may actually aid in sparing normal tissue. Lying on a belly board not only removes the bowel from the pelvis but also reduces pelvic setup variation. The type of radiation used in this study was helical TomoTherapy......... Posted by: Jessica      Read more         Source

October 28, 2007, 1:52 PM CT

IMRT provides quality care for head and neck cancer

Results from a University of Pittsburgh study demonstrate that intensity-modulated radiation treatment (IMRT) for head and neck cancer can be uniformly delivered in a large health care system of academic and community cancer centers through a centralized planning and therapy process. The findings were presented today at the 49th annual meeting of the American Society for Therapeutic Radiology and Oncology (ASTRO) in Los Angeles.

Our study demonstrates that it is feasible for head and neck cancer patients to receive IMRT in their own communities without sacrificing high-quality care, said Dwight Heron, M.D., associate professor of radiation oncology, University of Pittsburgh School of Medicine and director of radiation oncology, University of Pittsburgh Medical Center (UPMC). This is possible through an integrated network in which therapy is standardized across all cancer centers.

As per study results, there were no significant differences in toxicity profiles and therapy outcomes in 604 head and neck cancer patients treated with IMRT at 12 community cancer centers and one academic flagship facility. Two hundred and forty-eight patients (41 percent) were treated at the flagship facility, and 356 patients (59 percent) received IMRT at one of the community centers. All 13 centers, connected through a telemedicine network, followed the same clinical pathway guidelines for the radiotherapy management of head and neck cancer, which included specific details on volumes for radiation therapy planning and recommended doses of IMRT. When the researchers compared outcomes between the academic center and the community centers, they observed that there were no significant differences between survival or recurrence rates......... Posted by: Jessica      Read more         Source

October 15, 2007, 4:47 PM CT

Racial and ethnic differences in colorectal cancer

New research presented at the 72nd Annual Scientific Meeting of the American College of Gastroenterology emphasizes the importance of colorectal cancer (CRC) screening among racial and ethnic minorities, who have a higher occurence rate of colorectal cancer in comparison to Caucasians. Two studies found more African-Americans had advanced polyps on the right side of the colon than Caucasians, while results from colonoscopy screenings of Latin Americans revealed similarly high risk findings to African-Americans.

African-Americans have a high overall occurence rate of colorectal cancer and a greater prevalence of proximal or right-sided polyps and malignant lesions. The right side of the colon includes the cecum, ascending colon and proximal transverse colon and cannot be reached by flexible sigmoidoscopy.

The reasons for higher incidence rates in African-Americans are unclear; however, dietary, nutritional factors, rates of physical inactivity, variability in screening rates, lower use of diagnostic testing, and increasing smoking rates have been most usually implicated.

Dr. Roy D. Yen and colleagues from the University at Buffalo and the VA Western New York analyzed the results of 587 colonoscopies (78 African-Americans, 502 Caucasians) performed at their institution in 2004. The number and location of polyps and presence of advanced lesions between the two cohorts were examined. They found significantly more African-American patients (14 percent) had advanced right-sided, or proximal, polyps in comparison to Caucasian patients (5.4 percent). Scientists also found more black patients had advanced polyps, proximal polyps and proximal colon cancers than whites......... Posted by: Jessica      Read more         Source

October 12, 2007, 5:01 AM CT

Genome update defines landscape of breast and colon cancers

One year after completing the first large-scale report sequencing breast and colon cancer genes, Johns Hopkins Kimmel Cancer Center researchers have studied the vast majority of protein-coding genes which now suggest a landscape dominated by genes that each are mutated in relatively few cancers.

Their report, published online in the October 11 issue of Science Express, indicates that while little is known about these less-usually mutated genes, they can be grouped into clusters as per their pathways.

There are gene mountains represented by those that are frequently altered and have been the focus of cancer research for years, in part because they were the only genes known to contribute to cancer, says Bert Vogelstein, M.D., an investigator at the Howard Hughes Medical Institute and co-director of the Ludwig Center at Johns Hopkins. Now, we can see the whole picture, and it is clear that lower peaks or gene hills are the predominant feature.

In a systematic search of 18,191 genes representing more than 90 percent of the protein-coding genes in the human genome -- about 5,000 more than in the first screen -- the Johns Hopkins researchers observed that most cancer-causing gene mutations are quite diverse and can vary from person to person. They observed that an average 77 genes are mutated in an individual colon cancer and 81 in breast cancer. Of these, about 15 are likely to contribute to a cancers key characteristics, and most of these genes may be different for each patient......... Posted by: Jessica      Read more         Source

October 10, 2007, 4:45 AM CT

Potential breast cancer susceptibility gene

Like a crossword-puzzle solver who uses the letters in some answers to figure out others, scientists at Dana-Farber Cancer Institute and an international group of collaborators have used data on genes involved in inherited forms of breast cancer to identify a gene associated with non-hereditary cases of the disease.

Their approach, described in a study posted online by the journal Nature Genetics, didnt require any new experiments or lab procedures, but used standard analytic methods and "data mining" techniques to discover new cancer-related genes in information gathered from prior studies. The technique may help scientists find genes linked to other forms of cancer as well, plus non-malignant conditions that have a genetic basis, the authors stated.

"More than 85 percent of breast cancer cases dont have a hereditary link. That is, they arise in women who havent inherited an abnormal gene that increases their risk for the disease," said co-author of study David E. Hill, PhD, of Dana-Farbers Center for Cancer Systems Biology, where the research was based. "Science knows very little about which genes are involved in such cancers. Even among the 15 percent of breast cancers that do have a hereditary component, the responsible genes are known in only about three-quarters of cases"......... Posted by: Jessica      Read more         Source