Cancer Radiation : Hit Or Miss

"When I started training, we basically laid someone down on the bed, put a plastic mask on them and took some X-rays from the front and the side."

"We would then blast away at them every day for six or seven weeks, treating the same area irrespective of the fact that during the treatment the patient would lose up to ten percent of their body weight."

"Their body would shrink, the shape of the area we were radiating would shrink and, as they subsided and lost weight, the position of their head would slightly change and we wouldn't adjust one iota to that, we just carried on the way we were."

"The new technique cuts out a very laborious, time-consuming step without any detriment to our ability to target the cancer, as we found it to be 99.9 percent as good as a fully bespoke [patient-individualized] program."

Kevin Harrington, head, radiotherapy and imaging, Institute of Cancer Research, U.K.

 

Medical science progresses rapidly, as in a newly revealed cancer tool with the potential to dramatically reduce the time that patients require in radiotherapy for head and neck tumours, developed by British researchers. A machine combining MRI imaging and X-rays for a swift and accurate view of the tumour's location is revolutionizing this type of specific cancer treatment by adjusting the aim of the treatment, with an accuracy of 99.9 percent.

Time spent administering radiotherapy can be reduced from two hours to 30 minutes, according to the team of researchers representing the Institute of Cancer Research and The Royal Marsden NHS Foundation Trust, in London, England. Over 12,000 people are diagnosed with head or neck cancer annually in the United Kingdom, with treatment involving radiation to shrink a tumour while the patient lies motionless within a mask protecting healthy tissues.

In the most ideal of treatment situations, scans would be an every day occurrence in the creation of a bespoke program supervised by a doctor. Such an individually tailored and infinitely more accurate protocol however, is both time=consuming and labour-intensive. With the use of the MRI-Linac machine, the scientific team arrived at a middle ground between customizing the treatment, and the older, inflexible, prone-to-inaccuracy approach.

The method was used on two patients in a study published in the journal Clinical and Translational Radiation Oncology, and was found to be highly accurate. In over 50 doses of radiation delivered, one case only exceeded the acceptable threshold. The previous approach, in contrast, scored just 92.4 percent.

"The failure rate of the old approach was as high as seven percent which means that there was a significant risk of either missing the tumour target, and therefore reducing the chance of curing the disease, or overdosing the normal organs and increasing the risk of toxicity."

Kevin Harrington, Institute of Cancer Research