An Article published Online First and in an upcoming edition of The Lancet concludes that radiotherapy plus chemotherapy, with or without surgery, are both treatment options for patients with stage IIIA (N2) non-small-cell lung cancer. The Article is written by Dr Kathy Albain, Loyola University Chicago Stritch School of Medicine, Cardinal Bernardin Cancer Center, Maywood, IL, USA, and colleagues.

Non-small-cell lung cancer makes up some 80% of lung cancers, and its most common cause is long-term exposure to tobacco smoke. Of all cases of non-small-cell lung cancer, the disease is locally advanced in the chest only in about 30% (stage IIIA), where front-line surgery cannot cure the disease because it has already spread to lymph nodes in the centre of the chest (N2). In this phase III randomised controlled trial, the authors compared concurrent chemotherapy and radiotherapy followed by surgery with standard concurrent chemotherapy and radiotherapy without surgery, the current standard for this group patients.

Patients with stage IIIA (N2) non-small-cell lung cancer were randomly assigned to concurrent induction chemotherapy (two cycles of cisplatin [50 mg/m² on days 1, 8, 29, and 36] and etoposide [50 mg/m² on days 1-5 and 29-33]) plus radiotherapy (45 Gy) in multiple academic and community hospitals. If no progression, patients in group 1 underwent surgery and those in group 2 continued radiotherapy uninterrupted up to 61 Gy. Two additional cycles of cisplatin and etoposide were given in both groups. The primary endpoint was overall survival (OS).

202 patients (median age 59 years, range 31-77) were assigned to group 1 and 194 (61 years, 32-78) to group 2. Median OS was 23•6 months in group 1 versus 22•2 months in group 2 (a non-statistically significant difference). Number of patients alive at 5 years was 37 in group 1 and 24 in group 2. Progression free survival (PFS) seemed better in group 1 than in group 2, median 12•8 months versus 10•5 months; the number of patients without disease progression at 5 years was 32 (group 1) versus 13 (group 2). Lower white blood cell counts (neutropenia) and oesophagitis were the main grade 3 or 4 toxicities associated with chemotherapy plus radiotherapy in group 1 (77 [38%] and 20 [10%], respectively) and group 2 (80 [41%] and 44 [23%], respectively). In group 1, 16 (8%) deaths were treatment related versus 4 (2%) in group 2. In an exploratory analysis, OS was improved for patients who underwent lobectomy*, but not pneumonectomy**, versus chemotherapy plus radiotherapy.

The authors suggest the reason for an absence of effect of surgery could be inadequate power in the trial or reduced delivery of later chemotherapy (cycles 3 and 4) in the surgery group. However they say the mostly likely reason could be increased mortality following pneumonectomy, mainly due to acute respiratory distress syndrome and other respiratory causes. The authors conclude: “Chemotherapy plus radiotherapy with or without resection (preferably lobectomy) are options for patients with stage IIIA (N2) non-small-cell lung cancer… medically healthy patients with stage IIIA (N2) non-small-cell lung cancer should be assessed by a team skilled in multimodality treatment, and treatment options can be considered during assessment. On the basis of the findings of our study, patients should be counselled about the risks and potential benefits of definitive chemotherapy plus radiotherapy with and without a surgical resection (preferably by lobectomy).”

In an accompanying Comment, Dr Wilfried E E Eberhardt, West German Tumour Centre, University Hospital Essen of the University Duisburg-Essen, Essen, Germany, and colleagues say: “Can we undertake surgery in patients with stage IIIA (N2) NSCLC after induction chemoradiotherapy from now on? Yes, we can-selectively in patients with less extensive resection (eg, lobectomy) than pneumonectomy.”

Link to article

Source
The Lancet

HOUSTON, July 29 — Tanning beds have moved to the highest-risk cancer category of radiation sources in an update from the International Agency for Research on Cancer (IARC).

Citing evidence from case-control studies and a meta-analysis, the IARC monograph working group “raised the classification of the use of UV-emitting tanning devices to Group 1, ‘carcinogenic to humans,’ ” the authors reported in the August issue of The Lancet Oncology.

In a meta-analysis published in 2006, the IARC working group concluded that people who begin using tanning devices before age 30 have a 75% greater risk of cutaneous melanoma than the general population (Int J Cancer 2006; 120:1116-22).

The working group also cited case-control studies showing “consistent evidence of an association between the use of UV-emitting tanning devices and ocular melanoma.”

The IARC reclassified all forms of ultraviolet radiation as a single carcinogenic entity. Historically, mutations caused by exposure solar radiation had been attributed to UVB. However, the same mutation was identified in UVA-induced skin tumors in mice.

UVA, UVB, and UVC previously had been classified individually as “probably carcinogenic to humans” (group 2A in the IARC system). In the updated report, the IARC moved UV radiation as a whole into the highest-risk category, eliminating distinctions between UVA, UVB, and UVC.

With regard to other sources, the IARC working group found insufficient evidence to conclude that welders face an increased risk of UV radiation-induced ocular melanoma. However, the group said, “a full review of the carcinogenic hazards of welding will be undertaken with high priority.”

The working group also classified all forms of ionizing radiation as group 1. Forms of radiation affected by the action included radon, plutonium, radium, phosphorus-32, and radioiodines.

Working group member Nicholas Priest is an employee of Atomic Energy of Canada. Co-author Ron Mitchel is a consultant to Atomic Energy of Canada. Co-author Colin Muirhead disclosed a financial relationship with the UK Ministry of Defense. Co-author J. Hall disclosed a financial relationship with Electricite de France. Co-author A. Green disclosed a relationship with L’Oreal Recherche.

A new study by researchers at the Georgetown’s Lombardi Comprehensive Cancer Center finds a higher level of common household pesticides in the urine of children with acute lymphoblastic leukemia (ALL), a cancer that develops most commonly between three and seven years of age. The findings are published in the August issue of the journal Therapeutic Drug Monitoring.

Researchers caution that these findings should not be seen as cause-and-effect, only that the study suggests an association between pesticide exposure and development of childhood ALL.

“In our study, we compared urine samples from children with ALL and their mothers with healthy children and their moms. We found elevated levels of common household pesticides more often in the mother-child pairs affected by cancer,” says the study’s lead investigator, Offie Soldin, PhD, an epidemiologist at Lombardi. Soldin cautions, “We shouldn’t assume that pesticides caused these cancers, but our findings certainly support the need for more robust research in this area.”

The study was conducted between January 2005 and January 2008 with volunteer participants from Lombardi and Children’s National Medical Center who live in the Washington metropolitan area. It included 41 pairs of children with ALL and their mothers (cases), and 41 pairs of healthy children and their mothers (controls). For comparison purposes, the case pairs were matched with control pairs by age, sex and county of residence. Previous studies in agricultural areas of the country have suggested a relationship between pesticides and childhood cancers, but researchers say this is the first study conducted in a large, metropolitan area.

Urine samples were collected from all child-mother pairs and analyzed by the Centers for Disease Control and Prevention to look for evidence of organophosphates (OP), the chemical name of some household pesticides. The body breaks down OP into metabolites which can be tracked in urine samples. The researchers say pesticides were detected in the urine of more than half of the participants, but levels of two common OP metobolites, diethylthiophosphate (DETP) and diethyldithiophosphate (DEDTP), were higher in the children with ALL compared to the control children (p< 0.03 and p< 0.05).

Also for the study, the mothers completed a questionnaire to collect information about the family’s exposure to pesticides, their medical history, home and neighborhood characteristics, diet, and history of smoke exposure. More case mothers (33 percent) than controls (14 percent) reported using insecticides in the home (p< 0.02), however there was no correlation found between high levels of the OP metabolites in urine and reported use of pesticides.

“We know pesticides - sprays, strips, or ‘bombs,’ are found in at least 85 percent of households, but obviously not all the children in these homes develop cancer. What this study suggests is an association between pesticide exposure and the development of childhood ALL, but this isn’t a cause-and-effect finding,” Soldin explains. “Future research would help us understand the exact role of pesticides in the development of cancer. We hypothesize that pre-natal exposure coupled with genetic susceptibility or an additional environmental insult after birth could be to blame.”

The authors report no related financial interests. The study was funded by Lombardi’s Cancer Center Support Grant from the National Cancer Institute, and by philanthropic support from Debbie and Scott Amey.

Source:
Karen Mallet

Georgetown University Medical Center

Smokeless tobacco products, as used in Europe and North America, do not appear to increase cancer risk. A large meta-analysis, published in the open access journal BMC Medicine, has shown that snuff as used in Scandinavia has no discernible effect on the risk of various cancers. Products used in the past in the USA may have increased the risk, but any effect that exists now seems likely to be quite small.

Peter Lee and Jan Hamling, from P.N. Lee Statistics and Computing Ltd, carried out the analysis of 89 studies from the United States and Scandinavia. They found that, after adjustment for concurrent smoking, any effect of current US products or Scandinavian snuff seems very limited. According to Lee, “It is clear that any effect of smokeless tobacco on risk of cancer, if it exists at all, is quantitatively very much smaller than the known effects of smoking”.

In 2005 in US men aged 35 or over, there were a total of 142,205 deaths from seven cancers considered to be caused by smoking. If these people had never smoked, Lee and Hamling estimated that the numbers would have reduced by 104,737, with the reduction in lung cancer deaths, 79,195, being the major contributor. If smokeless tobacco was introduced to a similar population of never smokers, this meta-analysis shows that any increase in risk would be negligible compared to the lives saved by reducing cigarette use.

Lee said, “Our paper shows very clearly that, in marked contrast to smoking, smokeless tobacco use carries little or no risk of cancer. Concerns about possible effects of smokeless tobacco on oral cancer are answered by our analyses showing a lack of relationship based on the combined evidence from those 14 studies published since 1990 which allow adequate control for effects of smoking.”

Notes:
Systematic review of the relation between smokeless tobacco and cancer in Europe and North America
Peter N Lee and Jan S Hamling
BMC Medicine (in press)
http://www.biomedcentral.com/bmcmed/

Source:
Graeme Baldwin

BioMed Central

Researchers have devised a scheme for identifying genes in yeast that
could lead to the identification of new cancer genes in humans. The study
is
published online this week in the open-access journal PLoS Biology.

Cancers arise from the accumulation of mutations or genetic alterations
resulting in the uncontrolled proliferation of cells. However, the number
of
mutations accumulated during the evolution of cancerous cells is large,
making it difficult to identify which of the mutations are responsible for
the
cancer phenotypes. Identifying new genes that sustain cancerous growth is
a major challenge in the campaign against cancers.

Aneuploidy, an abnormality in chromosome number and structure, is a
hallmark of many cancer cells. One idea is that aneuploidy may cause
cancer by
changing the dosage or expression of oncogenes (cancer-causing genes).
After decades of research, only a handful of human oncogenes have been
identified, accounting for a tiny fraction of all cancers So methods of
identifying new oncogenes through their association with aneuploidy has
become an accepted strategy in the cancer field.

The Mcm4Chaos3 mutation causes a defect in an enzyme that unwinds DNA
during DNA replication and predisposes mice to mammary tumors. In this
study, a
team led by Bik Tye from Cornell University introduced the equivalent
mutation in yeast. Yeast with this mutation generate chromosomal
abnormalities
and yield faster growing progeny, a situation reminiscent of what happens
in tumors. Using the yeast genetics tools the researchers could show that
improved growth is not linked to aneuploidy, but to point mutations in
just a few genetic loci.

Pathways and genes that regulate proliferation rates are likely to be
conserved in all eukaryotes. So, by identifying mutations that give cells
a
growth advantage in yeast, the simplest of eukaryotes, will help guide
the search of cancer genes in humans.

Funding:
This work was supported by National Institutes of Health grant
GM072557 awarded to BKT. The funder had no role in study design, data
collection and analysis, decision to publish, or preparation of the
manuscript.

Competing interests statement:
The authors declare that no competing
interests exist.

Citation:
“Aneuploidy and Improved Growth Are Coincident but Not Causal in a Yeast Cancer Model.”
Li XC, Schimenti JC, Tye BK (2009)
PLoS Biol 7(7): e1000161. doi:10.1371/journal.pbio.1000161

Source
PLoS Biology

A new proposal from the Centers for Medicare and Medicaid Services (CMS) to cut payments for radiation therapy treatments would cause many cancer centers to close, stop accepting Medicare patients, lay off support staff and reduce services to cancer patients, according to a survey conducted by ASTRO, the American Society for Radiation Oncology.

New technology has allowed radiation oncologists to improve cancer cure rates while reducing side effects. However, on July 13, CMS announced proposed changes to the Medicare policies and payment rates for physician services, including radiation oncology, that would cut payments to radiation therapy services by nearly 20 percent. Community cancer centers, particularly those in rural and suburban areas, would be hardest hit. Running 2008 claims data from a sample of practices across the country showed overall impacts between 18 and 31 percent on the average practice, with some services receiving payment cuts by up to 44 percent. If approved, these cuts would take effect on January 1, 2010.

“Take, for example, Joyce Wittet from Ontario, Oregon, population 11,245. The 79-year-old retired teacher had breast cancer that was easily cured with radiation therapy. Fortunately, there is a cancer center 15 minutes away that accepts Medicare. If the cuts had caused her cancer center to close, she would have had to drive to a hospital nearly two hours away, roundtrip for six straight weeks. If faced with this option, Joyce might have had to choose between mastectomy or expensive travel costs to cure her cancer. Worse still, she might have even forgone treatment altogether until it was too late,” said Patricia Eifel, M.D., FASTRO, chairman of ASTRO and a radiation oncologist at M.D. Anderson Cancer Center in Houston. “We applaud Congress and the Obama Administration for their efforts to improve access to healthcare for more Americans. However, this CMS proposal would do just the opposite: limit access through longer waits to begin treatment, less time with doctors and longer, costlier drives to receive treatment.”

Five-hundred-fifteen individuals responded to ASTRO’s survey. For community-based practices, in the face of 30 percent cuts, two out of five say they would close their practice. Forty-seven percent of rural practices say they would close. Sixty percent of community practices with multiple locations will consolidate their practices. Among those community practices able to stay open, 54 percent say they will no longer accept Medicare patients and 68 percent say they will limit the number of Medicare patients they treat.

If the cuts force radiation oncologists to consolidate or close their practices, 43 percent said their cancer patients would be forced to travel more than 50 miles round-trip, for radiation therapy treatments. In rural areas, 81 percent reported that patients would have to travel more than 50 miles. Overall, 97 percent of community practices said the quality of care for cancer patients receiving radiation therapy would suffer due to the cuts.

“My center is not viable at greater than 20 percent cuts, and patients already drive an hour to us. They then would drive nearly two hours one-way to the next center. We are the primary service center for six rural counties and we are barely holding on as it is now in the recession. About four of 10 patients now have no insurance, and we treat them. With these Medicare cuts, we will be forced to close,” said a survey respondent from rural North Carolina.

Congressional leaders urge CMS to reconsider

ASTRO is running a series of ads on WTOP, Politico, Congressional Quarterly Today, Roll Call and in an AARP publication to raise public awareness of the proposed cuts and to encourage citizens to ask members of Congress to sign on to the bipartisan letter written by Reps. Lois Capps (Calif.), Parker Griffith, M.D. (Ala.), Sue Myrick (N.C.), and Mike Rogers (Mich.) urging CMS to reconsider. ASTRO praises the leadership of these representatives and more than 25 of their colleagues who’ve already committed to sign the letter.

“Radiation oncology is critical for the effective treatment of our nation’s cancer patients. While we need to work together to cut healthcare costs, lumping in radiation therapy with diagnostic imaging doesn’t serve our patients. We need to make sure that all cancer patients, including those who live in rural areas and depend on Medicare, have access to all the tools and resources they need to make a full recovery,” said Rep. Capps.

“As a radiation oncologist who practiced in the community setting, I am aware of how these severe cuts would limit access to life-saving radiation therapy for cancer patients. I am proud to be working on healthcare reform to expand access to high quality, effective care for cancer patients and all Americans, and I look forward to working with both parties as well as the administration to find a solution that averts these cuts and protects patient access to care,” said Rep. Griffith.

“Radiation therapy helped me survive breast cancer, as it has millions of other women. I believe CMS made a mistake by roping radiation therapy in with these diagnostic imaging changes. This doesn’t make sense if we’re trying to improve access to care. I’m honored to join my colleagues in protecting patient access to radiation therapy by asking Medicare to prevent these cuts,” Rep. Myrick said.

“Radiation oncology helps many people survive and even thrive after cancer diagnoses. There is no possible explanation for forcing cancer centers to close, stop seeing Medicare patients, lay off staff or use outdated equipment; doing so will certainly not help cancer patients. As a cancer survivor myself, I know how important it is to have access to every possible opportunity to fight for healing. Medicare patients should have the same opportunities to win their battle against cancer,” Rep. Rogers said.
Visit http://www.astro.org/medicarecuts/ for a copy of the survey and to see the bipartisan letter.

Source
American Society for Radiation Oncology

In the July 15th issue of G and D, Dr. Suzanne Baker (St. Jude Children’s Research Hospital) and colleagues report on their surprising discovery of cell-type specificity of PI3K signaling in the mammalian brain. This finding highlights the complexity of this clinically significant cell signaling pathway, and its relevance to the design of small molecule PI3K pathway inhibitors, to both maximize efficacy and minimize side effects.

The PI3K pathway is an intricate signaling cascade that regulates cell survival and growth under normal, as well as pathological conditions. In fact, the PI3K pathway is mutated in more cancer patients than any other. The signaling network is balanced by the PTEN tumor suppressor protein.

PTEN (Phosphatase and Tensin Homologue Deleted from Chromosome-10) is recognized as one of the most frequently mutated tumor suppressors in human cancer, and has also been associated with neurological diseases like autism. It functions primarily as a phosphatase (phosphate-group-cleaving enzyme) to antagonize PI3K signaling by dephosphorylating PIP3, the lipid second messenger that signals activation of the PI3K signaling cascade. Loss of PTEN results in the upregulation of PI3K signaling, through the increased phosphorylation of PI3K effectors such as the molecule, AKT. Thus, the PTEN/PI3K/AKT pathway represents an important target for drug discovery.

To study the role of the PI3K downstream effector molecule, PDK1, in mediating the effects of PTEN loss, Dr. Baker and colleagues generated a novel transgenic mouse strain deficient in both PDK1 and PTEN specifically in the brain. The researchers found that while some of the characteristic brain abnormalities arising from PTEN loss are corrected by the concomitant deletion of PDK1, others are not: Most notably, PDK1 did not rescue the migration defects associated with PTEN loss in neurons. PDK1-independent abnormalities in the brains of PTEN-deficient mice suggests that additional, alternate downstream effectors of the PI3K signal exist.

This finding underscores the consideration that, as Dr. Baker explains, “inhibitors that block downstream effectors in PI3K signaling may not correct all of the defects caused by loss of PTEN function.”

Dr. Baker’s team also observed differential feedback regulation of the PI3K pathway in different CNS cell types. Clinical evidence has shown that some human tumors achieve chemoresistance through the increased phosphorylation of the PI3K downstream component, AKT. Quite surprisingly, Dr. Baker and colleagues found that PDK1 deletion caused a selective, dramatic increase in the phosphorylation of AKT in glial cells, but not neurons, indicating unanticipated cell-type specificity in PI3K feedback regulation in the brain.

Further research will be needed to determine if PDK1, itself, represents a useful therapeutic target. However, this example of a cell type-specific response to PDK1 deletion supports the notion of personalized cancer treatment, in so far as emphasizing the relevance of tumor cell of origin and genotype to help predict which patients will respond positively to specific PI3K inhibitors.

Dr. Baker emphasizes that, likewise, “There may be profound differences in the effects of inhibitors on different types of normal cells, which could be relevant in terms of side effects induced by systemic treatment with a pathway inhibitor.”

Source:
Heather Cosel-Pieper
Cold Spring Harbor Laboratory

Researchers funded by the National Institutes of Health have completed a critical first step in the eventual development of a technique to retain fertility in women with cancer who require treatments that might otherwise make them unable to have children.

The researchers have developed a method to advance undeveloped human eggs to near maturity, in laboratory cultures maintained outside the body. The technique focuses on the follicle, a tiny sac within the ovary that contains the immature egg. The researchers were able to grow human follicles in the laboratory for 30 days, until the eggs they contained were nearly mature.

The research seeks to provide women who require a fertility-ending treatment with options for reproduction after their treatment is complete. Men facing such treatments can freeze their sperm for use at a later date. Female cancer patients have fewer options. Unlike sperm, eggs rarely survive freezing and thawing.

The accomplishment represents the successful completion of the first of three steps needed to preserve a woman’s fertility after radiation treatments or chemotherapy. For the next step, researchers will need to induce the egg’s final division, so that it contains only half the genetic material of its precursors. Finally, the researchers will have to demonstrate that they can freeze and thaw human follicles before growing them in culture.

“The new technique could provide an option for women and girls who have cancer and are not yet ready to start families,” said Duane Alexander, M.D., director of NIH’s Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), which funded the research as part of the NIH Roadmap Interdisciplinary Research Consortium program. “An additional benefit is that it will allow researchers to more closely follow the process by which immature eggs grow and mature. In turn, these observations may lead to new advances for treating other forms of infertility.”

The best option currently for a female cancer patient to preserve fertility is to collect eggs, fertilize them with sperm, and freeze the resulting embryos. But that technique may not be acceptable to all female cancer patients.

Researchers have already identified experimental methods to freeze entire ovaries or strips of ovarian tissue and implant them in a woman’s body when she is ready to have children. This is a good option for some patients, but it is possible that some cancer cells may hitch hike on the ovarian tissue and result in a new cancer after treatment is completed.

Developed by Teresa K. Woodruff, Ph.D. and Lonnie D. Shea, Ph.D., of Northwestern University’s Feinberg School of Medicine, and their colleagues, the new technique would avoid both concerns.

The findings were published online in Human Reproduction.

The new findings build on earlier efforts by the research team, who grew mouse follicles in culture, induced the eggs they contained to mature, fertilized them with mouse sperm, and implanted them into female mice to establish pregnancy. The earlier research is described in an article that appeared in The NIH Record, here.

The researchers made the new advance by suspending the human follicle in a three-dimensional matrix of a gel-like material. They then flushed the follicle with the same hormones and growth factors that the follicle would be exposed to inside a woman’s body.

In previous attempts to grow follicles, researchers had set the follicles on a flat surface, which the study authors now believe does not mimic closely enough conditions inside the body. These earlier attempts failed to develop good quality eggs that were healthy enough for fertilization.

For the current study, the researchers started with so-called secondary follicles, which are at an intermediate stage of development. They collected them from the ovarian tissue of 14 cancer patients.

During the 30-day experiment, the follicle grew and produced hormones and the immature egg matured just as it would inside a woman’s body. The researchers found that the follicles would grow if injected into a gelatin mixture. The gelatin (called alginate) provided three-dimensional support for the follicle, much like the support it receives inside the body.

“The researchers have demonstrated that the technique produces healthy eggs,” said Charisee Lamar, Ph.D., M.P.H., R.R.T., director of the Fertility Preservation Program in NICHD’s Reproductive Sciences Branch. “The next step would be to investigate the viability of follicles from frozen tissue.”

Another component of the NICHD program is attempting to grow follicles of monkeys in culture. The ability to do research on mouse and monkey follicles might lead to advances that could later be used to perfect the technique’s use with human eggs.

Reference: “In vitro grown human ovarian follicles from cancer patients support oocyte growth.” Human Reproduction.

Source:
Robert Bock
NIH/National Institute of Child Health and Human Development

New research published in the July issue of the Journal of the American College of Surgeons reveals that African Americans with gastrointestinal stromal tumors (GIST), a rare cancer that begins in the wall of the gastrointestinal tract, now have survival rates equivalent to those of Caucasians. Prior to 2000, African Americans were more likely to develop GIST and less likely to undergo surgical treatment for this type of cancer.

Racial disparities in survival rates have been demonstrated for a number of cancers, typically due to unequal access to care. Through the National Institutes of Health and Healthy People 2010, a national health promotion and disease prevention initiative, the federal government has set forth goals to explore, account for and minimize these disparities.

“Over the last decade, racial gaps in the treatment of GIST appeared to have closed,” said Michael Cheung, MD, DeWitt Daughtry Family Department of Surgery, University of Miami, Miller School of Medicine. “Both perioperative and long-term survival have improved among African Americans.”

“Our study suggests that better diagnosis and increased use of surgery - which still provides the best chance for cure - have contributed to improvements in care for African Americans,” said Leonidas G. Koniaris, MD, FACS, associate professor of surgery, DeWitt Daughtry Family Department of Surgery, University of Miami Miller School of Medicine, and surgical oncologist at Sylvester Comprehensive Cancer Center at UM. “In addition, increased access to new targeted therapies through medication assistance programs may be helping to eliminate racial disparities in cancer treatment.”

A statistical analysis was performed using the Surveillance, Epidemiology and End Results (SEER) database that identified 3,795 patients diagnosed with GIST and other intestinal mesenchymal tumors between1992 to 2005. Patient demographics showed 72.2 percent Caucasians, 15.6 percent African Americans, and 9.1 percent Hispanics. Survival was calculated from the time of initial diagnosis to the date of last contact or death.

Both perioperative and long-term survival had improved among African Americans since 2000. In patients diagnosed before the year 2000, 30-day surgical mortality was higher in African Americans (0.56 percent versus 0.76 percent Caucasians, p=0.012). After 2000, 30-day surgical mortality was equivalent between races (0.46 percent versus 0.35 percent for Caucasians, p=0.517).

Before the year 2000, three-year disease specific survival was better in Caucasians than African Americans (79.3 percent versus 75.1 percent, p=0.025). There was no racial difference in tumor stage (p=0.446) or grade (p=0.495), and African Americans underwent surgical procedures less frequently than Caucasians (p=0.003). Multivariate analysis correcting for patient demographics, socioeconomic status and clinical data demonstrated African American race and failure to undergo surgical treatment were independent predictors of poor prognosis. In patients diagnosed after 2000, three-year disease specific survival was nearly equivalent between Caucasians and African Americans (82.1 percent versus 80.7 percent, p=0.680) and African Americans underwent surgical procedures just as often as Caucasians (p=0.153) did. Multivariate analysis for patients diagnosed after 2000 demonstrated no difference in survival by race (p=0.126).

Source:
Sally Garneski
Weber Shandwick Worldwide

Lifestyle choices are pieces of the cancer prevention puzzle, but exactly which steps to take remain unclear, even to scientists. Still, more and more individuals are incorporating small changes into their daily routine such as drinking green tea in hopes of keeping cancer risk at bay.

Is it working? A large new Cochrane review of studies that examined the affect of green tea on cancer prevention has yielded conflicting results.

Researchers looked at 51 medium- to high-quality studies that included more than 1.6 million participants. The studies focused on the relationship between green tea consumption and a variety of cancers, including breast, lung, digestive tract, urological prostate, gynecological and oral cancers.

The comprehensive review analyzed studies conducted from 1985 through 2008. Many of the reviewed studies took place in Asia, where tea drinking is widespread and part of the daily routine for many.

The review appears in the latest issue of The Cochrane Library, which is a publication of The Cochrane Collaboration, an international organization that evaluates medical research. Systematic reviews draw evidence-based conclusions about medical practice after considering both the content and quality of existing medical trials on a topic.

“Despite the large number of included studies the jury still seems to be out on the question of whether green tea can in fact prevent the development of various cancer types,” said lead review author Katja Boehm, Ph.D. Since people drink varying amounts of green tea, and different types of cancers vary in how they grow, it is impossible to state definitively that green tea is “good” for cancer prevention.

“One thing is certain…green tea consumption can never account for cancer prevention alone,” said Boehm, a member of the Unconventional and Complementary Methods in Oncology Study Group in Nuremburg, Germany.

Three types of tea black, green and oolong come from the plant Camellia sinensis, and all contain polyphenols. Catechins, a subgroup of the polyphenols, are powerful antioxidants. Some say the polyphenols in green tea are unique, preventing cell growth and thus having the potential to prevent cancer.

The review found that green tea had limited benefits for liver cancer, but found conflicting evidence for other gastrointestinal cancers, such as cancer of the esophagus, colon or pancreas. One study found a decreased risk of prostate cancer for men who consumed higher quantities of green tea or its extracts.

The review did not find any benefit for preventing death from gastric cancer, and found that green tea might even increase the risk of urinary bladder cancer. Despite conflicting findings, there was “limited moderate to strong evidence” of a benefit for lung, pancreatic and colorectal cancer. None of the studies that simply observed a group of people over time found a benefit for breast cancer prevention. However, both of the case control studies which compare people without a condition to people with it found a positive association between green tea consumption and a decreased risk of breast cancer.

Nagi Kumar, Ph.D., director of Nutrition Research at Moffitt Cancer Center in Tampa, Fla., is optimistic about the potential for green tea in cancer prevention. “The substances found in green tea are certainly promising,” Kumar said. “The field now has progressed to where we [can]…test the effectiveness and safety of green tea polyphenols using a drug form similar to the constituents in tea to see if we can prevent cancer progression. Time will tell.”

Kumar said the Cochrane review was “more an inventory of studies completed rather than a systematic scientific review,” adding that “the discussion lacks a scientific approach in the interpretation of the discordant findings.”

Kumar also noted that several groups are conducting randomized clinical trials, including one comprising six institutions: the Moffitt Cancer Center and the James A Haley VA Medical Center, University of Chicago, Jefferson in Philadelphia, University of Florida and Louisiana State University.

Both scientists agreed that more research is a good idea. Boehm said she highly recommends the conduction of a large, well-designed, study with adequate green tea consumption levels.

“The review provides where we have been in this field of research and where we are going and how much more we have on hand,” Kumar said. “Although not as thorough as I would like it, it is a good quality review.”

Therefore, while the questions about green tea consumption and cancer prevention remain unanswered, one thing remains clear: It is fine to consume green tea if you enjoy it and it might prove beneficial in the over time.

“If not exceeding the daily recommended allowance those who enjoy a cup of green tea should continue its consumption,” Boehm said. “Drinking green tea appears to be safe at regular, habitual and moderate use at its recommended dosage of up to 1200 ml/day.” That comes to a little over five cups a day.

The Cochrane Collaboration is an international nonprofit, independent organization that produces and disseminates systematic reviews of health care interventions and promotes the search for evidence in the form of clinical trials and other studies of interventions.

Boehm K, et al. Green tea (Camellia sinensis) for the prevention of cancer. Cochrane Database of Systematic Reviews Issue 3, 2009.

Source: Health Behavior News Service

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