Thousands of bowel cancer patients could avoid being subjected to brutal radiotherapy treatment without a drop in survival, a study has found.
Currently, people with bowel cancer, which includes colon and rectal disease, have a high cure rate when given chemotherapy and radiotherapy ahead of surgery.
However, the radiation has severe side effects such as an increased risk of pelvic fractures, bladder issues and diminished sexual function.
The study of more than 1,000 people found that in locally advanced patients with mostly stage three rectal cancer, there was no drop off in survival for people who did not get radiotherapy when compared to the usual protocol.
Data show that four out of five patients (80.8 per cent) who had the new radiation-free approach were alive five years later, compared to 78.6 per cent with the current method which has remained largely unchanged since the advent of radiation therapy in the 1980s.
“There were no meaningful differences between the two approaches,” Dr Deb Schrag, chair of the Department of Medicine at Memorial Sloan Kettering Cancer Center and study lead author, told reporters at the American Society of Clinical Oncology annual conference in Chicago.
“Here’s the take-home bottom line: most intermediate-risk rectal cancer patients can be cured without needing pelvic radiation,” she said.
“Why is this a big deal? It’s a big deal because we have been radiating pelvises to treat this type of rectal cancer for the past 30 years.”
‘A major step forward’
Around 800,000 rectal cancer cases are expected to be diagnosed globally this year and around half are thought to be locally advanced rectal cancer.
Cancer Research UK’s chief clinician Professor Charles Swanton said thousands of people in the UK will be diagnosed with this type of disease every year and could now be spared the harmful ramifications of radiotherapy on the back of the findings.
“Pelvic radiotherapy is associated with major long-term side effects. I think avoiding radiation is a major step forward,” he added.
“It’s excellent for NHS resources, being able to avoid radiation and free up radiotherapy slots for other patients.”
The current standard approach to treating advanced bowel cancer is a five-and-a-half-week course of daily pelvic chemoradiation as well as chemotherapy.
“The reason radiotherapy is so important is that rectal cancer has a nasty predilection to come back in the pelvis which is a cause of enormous suffering,” Dr Schrag said.
“Although it works well, pelvic radiation has real toxicities. It impairs bowel, bladder and sexual function and has an increased risk of pelvic fractures and secondary cancers. It can also impair the function of the bone marrow which can affect chemotherapy in the future.
“We asked the question, could we use radiation more selectively and only give it to people who don’t respond to chemotherapy rather than giving the radiation to everyone as part of the standard? It’s not a new drug, it’s a de-intensification.”
Dr Pamela Kunz, an ASCO expert, commented on the findings: “This is really a case of less is more.
“The study shows that we can spare select patients from receiving radiation without compromising efficacy.
“This leads to improved quality of life and reduced side effects including things like early menopause, and infertility. This trial is practice changing.”
The research was presented at ASCO in Chicago and also published in the New England Journal of Medicine.