Skip to 0 minutes and 5 seconds In week one, we discussed that radiation therapy is a personalised treatment where each individual has their own treatment plan. However, many patients ask why the length of treatment and type of radiation therapy prescribed may be different, even for the same cancer. We’re going to answer this question by speaking with Dr. Laure Marignol, an associate professor in radiobiology at the Discipline of Radiation Therapy, Trinity College Dublin. Laure will outline the role of a radiobiologist in helping doctors to treat cancer patients. She will also tell us of the exciting developments ahead that help personalise patient treatments. Hello. My name is Laure Marignol. I am a scientist specialising in the field of radiobiology.
Skip to 0 minutes and 47 seconds I’m going to answer some of the most common queries about my job. What is radiobiology, and why is it important in radiation oncology? Radiobiology is a field of science that focuses on understanding how radiation affects the biology of cancer and normal cells. This knowledge is very important, and it helps with the design of radiotherapy treatment protocols. Can you explain to us your work as a radiobiologist? My work as a radiobiologist is mainly laboratory based. Our research group perform experiments using cancer cells in the laboratory, but we also collect blood and tissue specimens from consenting radiotherapy patients. These samples are very precious, and they allow us to determine whether our scientific discoveries are clinically relevant.
Skip to 1 minute and 35 seconds How does knowledge of radiobiology impact the decisions made in a radiation therapy department? The field of radiobiology was created at the same time as radiotherapy began to be used to treat disease. The work of radiobiologists, very early on, has had in mind the optimal delivery of radiotherapy treatments. For instance, it impacts decisions on how much radiation dose should be given to each treatment, how often the patient should be treated, and how we may be able to reduce the severity of side effects. Today, radiobiologists are working on new tools to provide doctors with clues as to how well the patients will respond to radiotherapy. With this information, doctor will be able to adapt each treatment to each patient’s requirement.
Skip to 2 minutes and 21 seconds This is what we call personalised radiotherapy. This approach is very exciting, and will likely improve the efficacy of radiotherapy. Why do some patients have fewer treatments in their course of radiation therapy compared to others? The number of treatments can change between patients, depending on the nature of the disease. For instance, we know that some tumours will be controlled better if we deliver a lot of radiation at each treatment, and therefore, this patient will not need as many sessions. Or the tumours are located close to healthy tissue that is easily injured by radiation. In this case, it is often better to deliver a small amount of radiation more frequently.
Skip to 3 minutes and 4 seconds Can you broadly explain, from a biological perspective, why patients experience side effects from radiation therapy? A malignant tumour grows in a very chaotic fashion. That means that the edges of the tumours are not very sharp, and can be very difficult to see exactly where the tumour ends. To ensure that we kill all of the tumour cell with radiation, we therefore have to give radiation to an area that is bigger than where we think the tumour is. This means that we cannot avoid giving radiation to healthy tissue, and that will generate side effects for the patient.
Skip to 3 minutes and 40 seconds What new developments in radiobiology will impact positively on patient quality of life in the future? I think that the biggest impact for patients will come from our ability, in the future, to personalise radiotherapy. First, there are new tools being developed, as we speak, that will tell whether a tumour would respond well, or whether a tumour might need a more aggressive treatment approach to respond fully. At the same time, radiobiologists are working with chemists, cancer biologists, and engineers to develop new treatments that will help also efficacy of radiation therapy. My work as a radiobiologist is innovative, that is, enables me to be creative and think and design new treatments for radiotherapy cancer patients.
Who's who: Radiobiologist
Radiobiology is considered a relatively new field of science, even though it has existed since the early 1900s. Radiation was seen as a miracle cure and used in medicine within years of discovery. Few discoveries these days would reach the clinic in such a short period of time!
While radiation therapy patients will not normally meet with a radiobiologist, the scientific community of radiobiologists interacts with clinicians and shares their determination to advance our ability to improve radiation therapy treatment delivery. Indeed, radiobiologists have had a huge impact over the years on the design of radiation therapy protocols.
For instance, they have helped doctors define the daily dose of radiation that can be safely delivered, how many doses should be given, and warned against the missing too many daily doses.
Today, our efforts are focusing on the exploitation of the most intricate analysis of a patient’s genetic make up to increase radiation therapy success.
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