Of Breast and Cancer
The pill lowers risk, benign lesions up it, treatment switch to anastrozole tames recurrence
Sigmoidoscopy fails to detect polyps
WASHINGTON
Sigmoidoscopy, a technique commonly used to check for colon cancer, fails to show precancerous polyps in two-thirds of women tested, according to a study published in the New England Journal of Medecine.
Earlier research had already showed a failure rate in men of 30 percent using the technique, which examines the lowest one-fourth of the colon, said the study financed by the National Cancer Institute.
"Our study found that the sigmoidoscopy results told us little if anything about the health of the colon beyond the lower one-quarter reached by the sigmoidoscope," said coauthor Andrew Flood, epidemiologist at the University of Minnesota Cancer Center and School of Public Health. "To detect polyps in the upper or proximal portion of the colon, which is where about two-thirds of the polyps found in study participants were, we need to rely on colonoscopy," said Flood.
The study was performed on 1,463 women aged between 50 and 79 years at four US military hospitals. The more expensive colonoscopy was recommended as a much more reliable test, used for exploratory examinations of the large intestine, and strongly recommended for people 50 years and older.
Contraceptive pill could lower breast-cancer risk
SYDNEY
Young women who have a family history of breast cancer could substantially reduce their risk of developing the disease by taking the contraceptive pill, according to new research. The study of 2,000 women with a genetic mutation, placing them at high risk of developing breast cancer, showed they were about four times less likely to contract the disease if they used the pill, lead researcher Prof. John Hopper said.
The research found that women with the BRCA1 genetic mutation, and therefore a 40- to 80-percent chance of developing breast cancer, reduced their risk to 10 to 20 percent if they used oral contraceptives. The results were the same in all three countries surveyed -Australia, the United States, and Canada.
Researchers say they don't understand how the hormones in the pill interact in the body to lessen the risk of the cancer, but they are supported by a previous study that found use of the pill reduced the risk of ovarian cancer. "These findings are important because women who carry a mutation in BRCA1 or BRCA2 (another gene linked to breast cancer) are also at increased risk of ovarian cancer," Hopper said.
The finding has surprised researchers at the University of Melbourne who had presumed the pill would have a harmful influence.
While Hopper is cautious about the findings, he said they could have major implications for women whose genetic make-up places them at high risk of developing breast or ovarian cancer and currently have no other means of preventing the disease except surgery.
Bone-marrow cells trigger breast cancer
HAMBURG, Germany
The hospital at Hamburg-Eppendorf said its researchers had found a way of detecting dormant cancer cells in bone marrow that can serve as an early warning sign in breast cancer cases. The technique enables them to see malignant cells likely to trigger a relapse in breast-cancer patients in remission.
The findings, published in the New England Journal of Medicine, are the results of 10 years of research in which more than 4,000 patients were studied. The technique could become widely used in three years and could one day help to prevent lung, prostate, stomach, and bowel cancer, said the head of the cancer-biology institute at the university, Klaus Pantel.
Risk still present despite some benign lesions
WASHINGTON
Women with benign breast lesions bear a higher risk of eventually developing breast cancer. A study published in the New England Journal of Medicine gave evidence for the need for women whose biopsies of breast lesions proved benign to remain wary of the possibility that a malignancy could later develop.
"Our findings indicate a link between select types of benign breast lesions and the later development of breast cancer," said Lynn Hartmann, an oncologist with the Mayo Clinic who led the study. Women who have a breast biopsy that is benign must discuss the possibility of additional risks with their doctors."
The Mayo team, which is examining risk factors related to breast cancer, showed after tests on 9,087 women that the most common types of benign lesions, those classified as nonproliferative, do not increase the risk of a subsequent malignancy. However, proliferative lesions that were benign in a biopsy were shown to have a high correlation to the later development of breast cancer.
Treatment switch boosts chances
PARIS
Women diagnosed with early breast cancer who switch treatment after two years on the mainstream drug tamoxifen can greatly improve their chance of avoiding a recurrence of the disease, a study published in The Lancet says.
Austrian and German doctors looked at data from two big trials in which patients were randomly assigned just tamoxifen for their postsurgery drug, or were switched to anastrozole, an aromatase inhibitor, after two years on tamoxifen. At a follow-up five years after surgery, women who made the switch to anastrozole were 40 percent less likely to have a recurrence of breast cancer. Of the 1,606 women in the tamoxifen-only group, there had been 110 cases of recurrence by the five-year mark. Among the 1,618 in tamoxifen-then-anastrozole group, there were 67 cases of recurrence.
The study was headed by Raimund Jakesz, a professor at Vienna Medical University.
Single-malt whisky can protect against cancer
LONDON
Single-malt whisky can beat the threat of cancer, thanks to high levels of a powerful antioxidant that kills cancer cells.
Dr. Jim Swan, an independent consultant to the global drinks industry, said that, according to research, single-malt whisky contains "more ellagic acid than red wine." He said that ellagic acid is an effective "free-radical scavenger" that "absorbs" or "eats up" rogue cells that occur in the body during eating. "The free radicals can break down the DNA structure of our existing cells, which then leads to the risk of the body making replacement rogue cancer cells," he said. "So, whether you indulge in the odd tipple, or you are a serious connoisseur, whisky can protect you from cancer--and science proves it."
Lesley Walker of Cancer Research UK finds the claim dubious.
"There is considerable data documenting the link between drinking excess alcohol and the increased risk of a number of cancers, particularly in smokers," she said. "Ellagic acid is a powerful antioxidant, but that does not mean it is necessary to hit the bottle," she said, noting that the ellagic acid can also be found in soft fruits.
Pineapple crush can fight cancer
SYDNEY
Australian scientists have discovered pineapple molecules can act as powerful anticancer agents and said the research could lead to a new class of cancer-fighting drugs.
Scientists at the Queensland Institute of Medical Research said their work centered on two molecules from bromelaine, an extract derived from crushed pineapple stems that is used to tenderize meat, clarify beers, and tan hides. One of the molecules--CCZ--stimulates the body's immune system to target and kill cancer cells. The other--CCS--blocks a protein called Ras, which is defective in 30 percent of all cancers.
Researcher Tracey Mynott said her team had set out to find why the enzyme-rich bromelaine crush had such strong effects on biological material. "In searching for these components, we discovered the CCS and CCZ proteins and found that they could block growth of a broad range of tumor cells, including breast, lung, colon, ovarian, and melanoma," Mynott said.
While clinical trials are a long way off, Mynott said the research had huge potential. "The way CCS and CCZ work is different to any other drug in clinical use today," she said. "Therefore, CCS and CCZ will represent a totally new way of treating disease and potentially a whole new class of anticancer agent."
The institute has launched a two-year study to examine the safety of the treatment and means of securing a reliable source of CCS and CCZ. If it succeeds it will seek a commercial partner to develop a drug that could be used in human clinical trials.
Combo treatment ups survival rates
PARIS
Combination treatment can double the survival rates for pancreatic cancer, a disease that has very high mortality, according to a small-scale study published by The Lancet.
Many patients with pancreatic cancer die within a few months of diagnosis because their condition is already far advanced by the time it is spotted. The standard treatment is a single chemotherapy drug, gemcitabine (Gemzar), which interferes with the growth of cancer cells. However, the survival rate is not good. Only 17 to 28 percent of diagnosed patients using gemcitabine survive beyond a year.
Italian researchers recruited 99 volunteers with pancreatic cancer and assigned gemcitabine-only treatment to 47 of them, while the other 52 were given gemcitabine in combination with other chemotherapy drugs--cisplatin (Platinol), epirubicin (Ellence), and flourouracil (Adrucil). After a year, about 40 percent of the group on the combination treatment had survived, twice that of the gemcitabine-only group.
The study was led by Michele Reni, an oncologist at the San Raffaele H. Scientific Institute in Milan, who suggests that a wider trial be carried out before the combination treatment is enshrined as the new standard.
Hong Kong researchers develop liver-cancer drug
HONG KONG
Researchers at Hong Kong's Polytechnic University have developed a drug that can prolong the life of liver cancer patients by several months. Scientists Thomas Leung, Thomas Lo, and Paul Cheng said their drug--called BCT-100--could lengthen the average life expectancy of a liver-cancer patient from six months now to 10 months.
It would cost US$3.8 million to create and was considered a first step in finding a more permanent cure for liver cancer, which kills some 1,400 people in Hong Kong each year, The Standard reported.
Human trials were to begin soon on the drug, which is made of an edible bacterium called Baccilus subtillis. The bacterium creates a natural chemical that kills off cancer-causing arginine proteins.
Childhood cancer linked to overhead power lines
PARIS
British researchers have found that children who had lived within 200 meters of high-voltage cables at birth faced a 69-percent higher risk of childhood leukemia. But they admitted there was no known biological mechanism to explain this, and that some of the association may have been due to chance.
The team looked through the records of more than 29,000 children in England and Wales who had had cancer, 9,700 of them leukemia, and compared this with the location of their homes in relation to power lines. Compared with those who lived 600 meters from power lines, children who lived within 200 meters faced an increased risk of 69 percent that they would develop leukemia. Those born between 200 meters and 600 meters faced an increase of 23 percent.
The study, published in the British Medical Journal, stressed that there remained a lot of uncertainty and added that even if the link were confirmed, power lines could be blamed only for about one percent of all cases of childhood leukemia in England and Wales.
The research was carried out by Gerald Draper and colleagues from Oxford University's Cancer Research Group and John Swanson, a scientific adviser at National Grid Transco, which is in charge of Britain's high-voltage infrastructure.
In 2001, the International Agency for Research on Cancer classified low-frequency magnetic fields as "possibly carcinogenic," but admitted that the data were sketchy.
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