In breast cancer we have so many research ongoing in radiation, of course in chemo and surgery as well. But for the radiation part the major change and shift is what we call de-escalation - I'm talking about radiation only moving from the six weeks of radiation on a daily radiation, now we are moving into three weeks with the hypofractionation, one week with the partial breast radiation, one day with in the intraop radiation or no radiation at all. So these are the most important changes that are ongoing in breast cancer. The challenge, though, is to find out who are the patients who would be eligible for each one of those.
So this is where the focus of the research right now and the discussion in the session was around the hypofractionation or this three week regimen, how to use it, who could benefit from it and if we can extend it to patients who have advanced cancer, not only the small and early stage cancers. So we discussed that.
The second point is discussion of the partial breast radiation technique and update on the latest trials and also discussion of the cases when we can avoid radiation therapy. In the past we used to give it for everybody but now, as we understand the biology and the natural history of some molecular types of breast cancer, we realise that all cancers are not the same and some of them could actually go without the use of radiation to avoid the toxicity of radiation. And as we understand more now about the biology and the molecular profiles of these tumours then we really can make a decision for patients and avoid the unnecessary treatment. Any time you can limit the treatment and retrieve the same level of cure it's a benefit for the patient.
In hypofractionated regimens all studies have shown that you decrease acute toxicity, which is the skin reactions mainly and the pain that the patient experiences during radiation. So this is very well proven that we have a decrease in acute reactions and in some studies there is improvement in cosmesis and the late effects, not all studies though. And one study, actually the largest study, has shown actually a benefit on survival. We don't know how and why but it is actually in the START UK trial where there is a benefit on survival. It has not been duplicated in other studies.
Are you aware of any ongoing trials that confirm the survival benefit?
There are no similar studies ongoing, there are no studies going to improve on the de-escalation in time. The current UK study that they call FAST-Forward is actually a combination of hypofractionation, lower dose per fraction, and a decrease in time. Now instead of three weeks we are moving to one week but treating the entire breast with 27Gy, which is quite a bit of a dose, but over one week. And I think this is a quite provocative design to see if we can compress all the treatment in five sessions. They have completed what we call the pilot, or phase II, study to see if it's feasible, not toxic, and they published no excessive toxicity and now the phase III comparative trial is ongoing.
So we are moving in this direction, at the same time we are moving in the direction of the partial breast radiation where we are treating only the site of the tumour in some low risk patients.
Any further points?
The very important topic that I discussed also at the end of my presentation was the importance of a very simple technique called deep inspiration breath hold to separate the heart from the chest wall and improve on the toxicity of radiation, vis-à-vis the heart, by pushing the heart away. And I urged the audience to practice this technique and to acquire this technique which is not very expensive just to improve on the tolerance of radiation therapy for breast cancers, specifically for left-sided tumours, because it's not allowed nowadays to still deliver incidental radiation to the heart because we can technically avoid it.