Combatting cancer in the third millennium – The contribution of medical physics

Abstract

In this invited opening Plenary Lecture at the 1st European Conference on Medical Physics, I indicated some of the roles of medical physics, and specifically medical radiation therapy physics, in the development of improved cancer care for the third millennium. It is said that you are only asked to predict the future if you are seriously old and/or will not be around long enough to know if you were correct. Hopefully, however, I will be able to contribute to this field for many years to come and many of my suggestions will be enacted. “Crystal ball gazing” is, however, a very unscientific process. Scientists are trained to study and analyse situations, report their findings and stop at that. “Future gazing” is not predicting the short-term developments; it is about being bold, radical and stating what today is impossible or almost unthinkable. So-called “scientific prophets” can be entertaining (which I also hope I was in this lecture) but at worst look egocentric and possibly ridiculous. I seem to have survived three previous requests to make scientific predictions [Webb S. The future of photon external-beam radiotherapy: the dream and the reality. Physica Medica 2001;17(4):207–15; Webb S. Radiotherapy physics: the next ten years of technical development. Imaging and Oncology 2005;1:43–50; Webb S, Evans PM. Innovative techniques in radiation therapy editorial, overview and crystal ball gaze to the future. In: Webb S, Evans PM, editors. Innovative techniques in radiation therapy. Seminars in Radiation Oncology 2006;16(4):193–8]. I proposed that important progress usually comes from two quite distinct directions. Firstly, there is “big hit science”, that is discoveries or inventions so important that the medical world changes forever because of them. These are what people remember, what reaches the media and what make some people household names. These are rare. Secondly, there is “incremental development” which is how the vast majority of scientists work. Small parts of a big problem are dissected out, solved and contribute to the progress of a bigger field. Sometimes the second way leads to the first, often unplanned to be so. To set the scene I briefly told the story of a few famous “big hit science” stories in which medical physicists have played a leading role – the invention of X-ray computed tomography (CT), the development of intensity-modulated radiation therapy (IMRT) and the invention of the emission tomography imaging modalities: single-photon emission computed tomography (SPECT) and positron emission tomography (PET). I suggested some of the areas I consider important for development. Some are fairly easy to identify and others are more speculative and unusual. I suggested that the goal of medicine and supporting science is to ensure that people live long and die quickly and I contrasted this with the past scenarios. Digressing to philosophy I suggested that there may be a difficulty in that the highly developed world works mainly to make itself even more developed and that many developed governments and aspiring medical physicists may not be as interested as they should be in assisting developing countries. There is therefore, sadly, likely to be an ongoing imbalance of resources. Scientific publishing is also at cross roads where the need to act independently, openly and with wide availability clashes somewhat with the need to generate revenue and support learned societies. Turning to detailed observations, I described how I think the following fields can be advanced: (1) improving the diagnosis of disease, (2) improving the planning of radiotherapy, (3) improving the delivery of radiation treatment and (4) improving the assessment of response to treatment. I ended on a highly philosophical note, which is somewhat critical of how much practical medical physics is currently organised in universities and hospitals and I suggested what should be the real agenda for scientific progress.