Showing posts with label cancer. Show all posts
Showing posts with label cancer. Show all posts

Thursday, December 09, 2010

Should healthy middle-aged people take daily aspirin ?

Studies have shown that aspirin, a commonly used painkiller, is linked to reductions in heart attacks and strokes, but it can irirtate the stomach and cause serious internal bleeding particularly in elderly people.

According to a new Oxford Univeristy study, published in The Lancet last week, taking a daily low dose of aspirin for reduced cancer deaths during and after the trials and the benefit increased with duration of treatment.

The researchers examined the data of 8 trials that looked at the effects of daily dose of aspirin on preventing heart attacks involving over 25,000 people. They found that aspirin reduced cancer deaths by 20% during the trial, but after 5 years, death rates were 34% lower for all cancer deaths. They also found the risk of all cancer deaths over a period of 20 years remained 20% lower for those who had taken aspirin, about 40% for bowel cancer, 30% for lung cancer, 10% for prostate cancer and 60% for oesophageal cancer. But there were not enough women participants to determine if daily aspirin could reduce breast, ovarian or endometrial cancer deaths.

The lead researcher said this study confirms the results of the previous study that found aspirin has preventive effect against cancer and has demonstrated a major new benefit of the drug. He believes that the findings have implications for guidelines on use of aspirin and the most benefit would be seen for those start taking aspirin between the age of 40 - 50 and continue for 25 years.

The previous study by the same authors, also published in The Lancet in October 2010, showed that a low dose of aspirin, 75mg per day taken for several years, reduced deaths due to colorectal cancer. However, opinions were divided on the result of the study.

Some said that the study did not give a balanced view of the effect of the treatment because it did not report the potential harms. The protective effects against cardiovascular disease were thought to be small for healthy adults. Some advised that aspirin should not be used to prevent heart attacks and strokes in "healthy" people as the risks outweigh potential benefits. Others said more research is needed before recommending taking aspirin to reduce cancer deaths.

Source: Rothwell PM, Fowkes FGR, Belch JFF, et al. Effect of daily aspirin on long-term risk of death due to cancer: analysis of individual patient data from randomised trials. The Lancet. 2010 Jan 7. [Epub ahead of print] Online publication 7 December 2010 ( f/t via Athens)


Previous studies :

Rothwell PM, Wilson M, Elwin C-E et al. Long-term effect of aspirin on colorectal cancer incidence and mortality: 20-year follow-up of five randomised trials. The Lancet 2010, Early Online Publication, October 22 (f/t via Athens)

Benamouzig R, Uz B. Aspirin to prevent colorectal cancer: time to act? The Lancet 20110, Early Online Publication, 22 October (f/t via Athens)






Wednesday, December 09, 2009

Transplanting kidneys with renal masses

According to the December issue of BJU International, surgeons at the University of Maryland have transplanted 5 kidneys that have been affected by a renal mass, 3 were cancerous. So far, 1 of the recipients has died in an accident, the remaining 4 have survived between 9 and 41 months without develoing cancer.


The head of the team, Dr Michael Phelan, said both patients and the donors were aware of the cancer in the donor kidneys and the risks including recurrence of the cancer. Before the transplanting into the recipients, the surgeons removed all visible traces of the tumours. Such approach is "controversial and considered high risk" said Dr Phelan, but "The current study provides evidence to suggest that kidneys from donors with renal masses offer a minor, yet feasible, solution to the current organ shortage" and "can be transplanted into recipients with limited life-expectancy on haemodialysis after careful removal of the renal masses".


Source : "Living-donor renal transplantation of grafts with incidental renal masses after ex-vivo partial nephrectomy" BJU International, December 2009, Volume 104, Number 11 (f/t via Athens)

Friday, October 09, 2009

telomeres and the 2009 Nobel Prize

3 American scientists, Elizabeth H. Blackburn, Carol W. Greider and Jack W Szostak, won the 2009 Nobel Prize in Medicine for their research into telomeres and telomerase that led to new insights into aging, cancers and some inherited disease and could lead to new treatments for the diseases.

Their work solved one of the mysteries of how cells duplicate without losing pieces of the chromosomes. Chromosomes are strands of DNA that carry genes. Blackburn found that at the end of each of the chromosomes was the repeating DNA sequence – CCCCAA. Szostak had developed mini-chromosomes and found that each time the cells divided, the mini-chromosomes degraded and eventually vanished completely.

Blackburn and Szostak collaborated in 1980 and made mini-chromosomes with the CCCCAA sequences at either end. They found that when these were injected into yeast, the DNA sequence protected the chromosomes when they were copied. They called the caps “telomeres”. In 1984, Greider, Blackburn’s student, discovered the enzyme, “telomerase”, that makes telomeres.

Further studies discovered that healthy telomeres delayed the aging process in cells, prompting research into anti-aging treatments. Related studies found that defective telomeres had affected the division of bone marrow stem cells and overactive telomerase was associated with the development of cancer.

However, a member of the Prize Committee said that large questions remain to be answered about the working of telomeres and telomerase. Merck, a drug company, is currently running a trial of a cancer vaccine designed to train the body to attack tumor cells that produce telomerase.

Wednesday, September 03, 2008

Vytorin's cancer saga

The New England Journal of Medicine published an editorial yesterday on its website rising the doubts of the safety of the drug Vytorin and its cancer link. It concludes that “physicians and patients are unfortunately left for now with uncertainty about the efficacy and safety of the drug”.

Vytorin is a combination of 2 drugs : a statin called simvastatin and ezetimibe, a new drug for lowering cholesterol . Vytorin is one of the best-selling drugs in the world and heavily prescribed by doctors although there is little evidence that ezetimibe offers the same benefits as stains.


The SEAS trials of Vytorin, conducted by reserachers in Norway found that Vytorin lowered the average levels of “bad” LDL cholesterol but not the aortic valve disease. It also found unexpectedly more cancer cases among patients taking Vytorin than the placebo.


This has prompted the analysis of the ezetimibe trials by Oxford researchers. When the results from all trials were combined, they did not find an increased incidence of cancer and they concluded that there is "no credible evidence of any side effect of ezetimibe on cancer risk". However, they suggest that “follow-up of longer duration will permit the balance of risks and benefits to be determined more reliably.”

Source: Both articles are published online on Sept 2 at the NEJM website ( will appear in Sept 25 issue of the journal)