Improving radiotherapy for prostate cancer
06 August 2007 - Over the past decade, modern technologies have transformed radiotherapy. We have the ability to treat patients more safely than ever before, accurately determining correct dosages and reducing the side effects of previously dehabilitating treatments.
David Dearnaley, Professor of Uro-Oncology and Honorary Consultant in Clinical Oncology, explains how prostate cancer sufferers have benefited from the modern-day advancements.
One advancement has been in external beam radiotherapy. Previously machines have produced target beams that were square or rectangular and therefore not mimicking the exact shape and form of cancers. "The development of multileaf collimators (MLC), where individual segments or leaves can move independently, enables us to shape beams to match the cancer in steps from 10mm to as little as 2mm across," explains Professor Dearnaley.
Another major advancement in radiotherapy has been the increase in power and speed of computer systems. Originally, the planning physicist added the dose contributions of three or more radiation beams together using their experience and skill to produce the dose distributions to treat the patient. It is now possible to tell the computer to give a specified high dose to the target and a lower specified acceptable dose to the surrounding normal tissues. The computer algorithm works backwards from these instructions to produce a plan. Combining this process with MLC produces what is called intensity modulated radiotherapy, which can produce very complex target shapes, substantially avoiding sensitive surrounding normal tissues. "This gives opportunities to both increase the dose to the cancer - improving control rates and reducing the dose to surrounding normal tissues - limiting the side effects which determine the dose that can be safely given," concludes Professor Dearnaley.
Read more about Professor Dearnaley's work in The Institute's Annual Research Report 2006.
Find out more about Professor Dearnaley's research at The Institute
