Breakout Group C Summary and Recomendations with Group Discussion: Improving Therapy and Reducing Morbidity of Primary Therapy for Localized Disease

SLIDES & TRANSCRIPTS
Tuesday, June 18

Breakout Group C Summary and Recomendations with Group Discussion: Improving Therapy and Reducing Morbidity of Primary Therapy for Localized Disease

Peter W.T.Pisters , MD

Slide 1:

DR. PISTERS: I also would like to thank the organizing committee for the privilege of working with Bob and the rest of the local management team. Before I begin, maybe I will just add my own personal thoughts to the dialogue about the tissue banking and biopsy issue. I think, if our goal here is to develop recommendations for future research, I think we would be remiss if we did not include, among our recommendations, an initiative to investigate the feasibility of a collaborative tissue bank. I personally feel that has got to be among the list of recommendations, or we won't make progress.

With that, I will move briefly through the issues specific to retroperitoneal sarcoma. These were the points where we found general agreement, and I will just step through these quickly. First, I think there is general acknowledgement that local control is a major problem for all patients with this disease.

Secondarily, distant metastatic disease is also a significant problem for the subset of patients who have high-grade retroperitoneal lesions.

There was a general consensus with our group that at this point in time, surgery with attempted R0 or R1 resection remains the standard of care for this disease, and that radiation treatment remains investigational. Based on the pilot data available from several centers, it appears that pre-operative radiation is feasible and may be considerably less toxic than post-operative radiation, for reasons that Brian articulated yesterday very eloquently.

Slide 2:

One research strategy that was proposed here is basically based on the proven benefit of extremity sarcoma, where it appears now, for this disease, the main therapeutic question is does radiation treatment improve local control?

There is general acknowledgement among our group that, given the rare nature of these tumors, that collaborative research efforts are essential and for a trial to be successful this would most certainly need to be international in scale. To follow up on the recommendations of some of the other groups, I would agree that a consortium, perhaps on an international scale, would be essential to help complete a trial like this.

There is already an existing Cooperative Group trial in this disease in this country, and that is a fairly small sample size study of 48. I think it seems fairly intuitive that, if that trial cannot be completed, it is probably unlikely that a successful phase III trial that might conceivably involve hundreds of patients could be successfully completed in this country.

Slide 3:

The last issue that we discussed at some length was the structure of a potential trial, and I won't go through this extensively.

The question that we identified, obviously, is surgery alone versus pre-operative radiation followed by surgery.

It seems intuitive that the primary endpoint for such a trial would be local control. And some of the issues that we grappled with and discussed at length included whether such a trial should be limited to patients with primary retroperitoneal sarcomas, or whether patients with local recurrence should be included in such a study, or whether all grades should be included, and whether there should be some provision to facilitate use of chemotherapy among patients with high-grade lesions, in order to facilitate maximum participation.

I think overall there was a consensus that, for a trial of international scale, that the study must be simple in design. I will stop there and take questions and comments. Thank you.