Radiotherapy cuts bowel cancer recurrence: study

LONDON (Reuters) - Giving bowel cancer patients radiotherapy before surgery to remove the tumour, rather than after, can reduce the risk of the disease recurring to as little as one percent, researchers said on Monday.

Surgery is the standard treatment for the illness but there is still a risk that the cancer can return. If it does, the disease is more difficult to treat and often incurable.

In a international study known as the CR07 trial, British scientists compared the impact of giving radiotherapy before surgery and after on 1,350 patients in Britain, Canada, South Africa and New Zealand.

They found that patients in the pre-operative group had a lower rate of recurrence and a better five-year survival rate.

"The results of the CR07 trial show that giving a patient radiotherapy before rectal surgery gives them the best chance of avoiding re-growth of the cancer and of survival in the longer term," said Dr David Sebag-Montefiore, of the Cookridge Hospital in Leeds.

Patients in the pre-operative group of the trial, which was presented at the National Cancer Research Institute (NCRI) meeting in Birmingham, England, were given five daily treatments of radiotherapy followed by surgery within two weeks.

In the post-operative group, surgery was followed by 25 radiotherapy sessions over five weeks and chemotherapy if necessary.

Five percent of patients who had pre-operative radiotherapy had a local recurrence of the cancer after five years, compared to 17 percent in the other group. They also had a 75 percent chance of five-year survival while in the post-operative group it was 67 percent.

"This is good news for patients and clinicians alike and could lead to an increase in the use of pre-operative therapy," Sebag-Montefiore added in a statement.

Bowel cancer kills nearly half a million people worldwide each year. In developed countries it is the second most common cancer, according to the International Agency for Research on Cancer (IARC). Most cases occur sporadically but about 5 percent of patients have a family history of the disease.