Radiotherapy before surgery minimises risk of recurrence of bowel cancer
9 October 2006
Birmingham, UK. An international clinical trial has
found a way to minimise risk of tumour recurrence in bowel cancer patients
to as little as 1% when combined with successful surgery.
The UK Medical Research Council (MRC) trial, looked at data from 1,350
patients from 52 centres in the UK, Canada, South Africa and New Zealand
between 1998 and August 2005. The results were presented at the NCRI Cancer
Conference in Birmingham, UK, this week.
Traditionally, surgical removal
of cancer found in the lower 15 cm of the bowel (rectum) has been the
treatment of choice. However, simply removing the tumour leaves a risk of
re-growth within the bowel and surrounding tissues. Not only is this
recurrence incurable in the majority of patients, but it causes distressing
symptoms that are difficult to control.
The CR07 trial compared routine
use of radiotherapy before (pre-operative) with a selective use after
(post-operative) surgery to reduce the risk of recurrence.
In the pre-op
course, patients were give five daily treatments of radiotherapy followed by
surgical removal of the tumour within two weeks.
In the post-op group, 10%
of patients were selected to receive twenty-five daily treatments of
radiotherapy over a five-week period combined with chemotherapy after
surgery. Patients were selected for chemoradiotherapy if cancer cells were
found within 1mm of the edge of the removed tissue. This was determined by a
pathologist, the specialist who conducts a detailed examination of the
removed bowel using a microscope.
Comparison of the overall treatment
approaches found that only 5% of patients in the pre-op group had local
recurrence of the cancer after five years, compared with 17% of the post-op
group. It also found that pre-op patients had a higher chance (75%) of being
alive five years later that the post-op patients (67%).
A benefit from the
PRE regime was seen irrespective of the position of the cancer or quality of
surgery received. However, the combination of PRE and the best surgery
resulted in almost complete elimination of the risk of local cancer
recurrence (1%). The trial also confirms that quality of surgery is directly
linked to risk of local recurrence.
Principal investigator Dr David Sebag-Montefiore, consultant clinical
oncologist from Leeds, said on behalf of the MRC Clinical Trials Unit:
‘There are approximately 35,000 cases of bowel cancer diagnosed every year
in the UK alone. The results of CR07 trial show that giving a patient
radiotherapy before rectal cancer surgery gives them the best chance of
avoiding re-growth of the cancer and of survival in the longer term.
is good news for patients and clinicians alike and could lead to an increase
in the use of pre-operative radiotherapy in the UK. The trial results show
that patients should have the opportunity to discuss the benefit of
radiotherapy before rectal cancer surgery.’
Research Institute (NCRI):
NCRI Cancer Conference: