Drug may double cancer risk: study

Researchers from the University of Oxford’s Cancer Epidemiology Unit and the Medicines and Healthcare products Regulatory Agency found that those who have taken oral bisphosphonates for over five years are twice as likely to develop the cancer than those who have not.

Oral bisphosphonates are a type of drug used to treat osteoporosis and other bone diseases and are the most commonly recommended treatment for such conditions.

The experts,who used a huge public database to analyse the disease,found that it increased from 1.5 to three per 1,000 men and from 0.5 to to one per 1,000 women.

Among those aged 40 and over,2,954 had oesophageal cancer,2,018 had gastric cancer and 10,641 had bowel cancer,all diagnosed between 1995 and 2005.

The results also showed that the chance of oesophageal cancer was 30 per cent higher in people with one or more previous prescriptions for oral bisphosphonates,compared to people who had never taken the drugs,the Telegraph reported.

The risk was almost double for those who had 10 or more prescriptions compared with those who had had between one and nine,according to the study.

However,the researchers,who looked at the use of oral bisphosphonates,including Fosamax,and three types of cancer,said there were no links between the drugs and stomach or bowel cancer.

Dr Jane Green,lead author of the study,said their results were “part of a wider picture” because bisphosphonates were “increasingly prescribed to prevent fractures”.

She said: “what is lacking is reliable information on the benefits and risks of their use in the long-term.”

But she added: “Oesophageal cancer is uncommon. The increased risks we found were in people who used oral bisphosphonates for about five years,and even if our results are confirmed,few people taking bisphosphonates are likely to develop oesophageal cancer as a result of taking these drugs.”

Their study contradicts one published only a few weeks ago,using the same dataset,that showed no link between the drugs and the disease.

However,the latest research followed patients for almost twice as long and had greater statistical power.

A spokesman for the MHRA said there is no need for patients to stop taking their bisphosphonate medicine on the basis of the findings of this study.

The findings are published in the British Medical Journal.