ASCO 2010 Annual Meeting, 4—8 June 2010, Chicago
Interview with Dr Bridgette Rack (Munich University Hospital, Germany)
What have you been talking about at the annual ASCO 2010 meeting?
Circulating tumour cells in breast cancer. We conducted the Success Trial, which is a large trial of 3,500 patients with primary breast cancer, and they were treated with two different chemotherapy regimens and a bisphosphonate treatment afterwards. We monitored circulating tumour cells in almost of all of these patients and the data on the circulating tumour cells is what we are presenting today.
Do you consider circulating tumour cells to be stem cells?
We didn’t check in our trial, but there is some data that finds a high proportion of stem cells in the CTC population, so this might be reasonable.
What is the prognostic relevance of circulating tumour cells?
I think the prognostic relevance in metastatic breast cancer has quite a good basis. In the adjuvant setting there are some trials – I believe the Success Trial is probably the largest, and we could show prognostic relevance for CTCs before the start of chemotherapy after surgery for tumour removal. And we have a strong trend for circulating tumour cells after the end of chemotherapy, so that’s persistent cells that survive chemotherapy. And in this trial we also looked for CTC samples after two and after five years, but this is still ongoing.
What is the future for the SUCCESS Trial?
We have already started a treatment randomisation based on this prognostic data. But if you go beyond that, I believe that circulating tumour cells have a prognostic relevance. At the moment we have a couple of issues concerning the technique, the sensitivity of the systems. But if you could use any technique to select high risk patients after our normal standard treatment, you could treat these patients with additional treatment options and perhaps you could achieve an improvement for survival.
What is the message for the doctor in the clinic?
I think this is not something that’s really for prime time at this moment, to take it into clinical practice, but anyone who has the chance to participate in any trial, who has a translational program evaluating things like that, I think this will get us forward and perhaps implement these techniques in the future.
Why would patients be interested in this type of research?
What we are trying to do with several kinds of translational research work – CTC is just one part – is to make treatment more individualised. So this will increase the efficacy of the treatments we have and, on the other hand, it will also spare side effects. But this is still something for the future, unfortunately.