Scientists at the University of Hong Kong have homed in on the specific cancer stem cells that are responsible for the usually fatal spread of colorectal cancer to other organs.
The research finding, described as revolutionary, marks a paradigm shift in dealing with colorectal cancer. Current treatments regard all cancer cells homogenously and try to eliminate them all via chemotherapy or surgery.
'It will revolutionise the approach to cancer treatment in future,' said one of the researchers, Ronnie Poon Tung-ping, an HKU professor in surgery. 'If you just target mature cancer cells, you are not targeting the roots of the disease. What the industry needs to work on now is drugs that will target cancer stem cells.'
The breakthrough will allow doctors to predict high-risk patients whose cancers are liable to spread - in a process known as metastasis - accurately before it occurs.
Treatments can also be developed that specifically target these cancer stem cells, called CD26+.
Scientists do not know how CD26+ cells come about. Such cells are not only resistant to chemotherapy but can be enriched by the process. More than half of patients who undergo colostomies, where part of the colon is removed, still experience metastasis.
The study found that even when most of the cancerous cells were eradicated and the tumour appeared to shrink, it could take as few as 1,000 cancer stem cells for it to regrow. These cells can change into various cell types and drive the spread of tumours, sometimes exponentially.