Autologous Bone Marrow Transplantation - Blog Science Connections

450 Panel Discussion: Session III
What is the role of computerized analysis to help us define objective criteria
for tumor cells?
DR. SEEGER: As 1 understand the first question was how can we find so
many marrows that are positive when you don't find so many positives? I think
that is a function of how many cells you look at. 1 don't know how many you
are looking at, but we look at at least 300,000 cells by monoclonal antibody
and another 300,000 by neuron-specific enolase (NSE) staining. So that's a
total of 600,000 cells. I think that is the first point. The second answer is that
we do not call a cell malignant unless we are convinced morphologically and
by staining that it is a malignant cell. We do occasionally see very small cells
that look like lymphocytes that stain with this cocktail for antibodies. Those
cells are not called tumor cells.
DR. K. DICKE: I have a question for you and for the other speakers.
Basically, listening as an outsider to neuroblastoma, what is really striking to
me is that in your studies you come up with prognostic factors that enable you
to do bone marrow transplants in prognostically poor patients. Why are you
the only one who is doing that? Is there a discrepancy between interpretation
of prognostic factors?
DR. SEEGER: 1 think those of us working in neuroblastoma would take
that as a compliment. I think many of us feel very strongly that even with
transplants we will be able to define prognostically different groups and that is
why we are continuing to use these factors. We have had a long-standing
interest, at least I have, in prognostication, and 1 think it will be useful.
DR. DICKE: Dr. Philip, what is your idea about it?
DR. PHILIP: 1 agree with what you just said and my comment would be
that it is true that the Seeger study is a very important one because it is the first
randomized study in which the question has been asked prospectively. But it
is a first step; not everything can be solved by a randomized study. We know
that high-dose melphalan should be included in our next study, and we also
know that it may have a positive effect on disease-free survival. 1 think that the
prognostic factors will still be valid even if we are able to increase the diseasefree
survival rate.
DR. DICKE: That means that you plan to include these prognostic factors
in your next study?
DR. PHILIP: Certainly, 2 weeks ago we had a meeting on prognostic
factors.
DR. SEEGER: That is an important point. We had a meeting with most of
the people in the world involved in neuroblastoma, 2 weeks ago, and arrived at
recommendations that are standard recommendations for staging and
response rate criteria. We anticipate another meeting in about a year that will
incorporate many of these new prognostic factors which can then be used