Autologous Bone Marrow Transplantation - Blog Science Connections

526 Panel Discussion: Session V
small cell cancer just as the number of patients referred for this procedure is
falling dramatically. We don't seem to be generating studies on defined groups
of patients adequately to prove our points, but instead Hillard, who may have an
interesting program, is investigating primarily relapsed patients. I'd like to hear
where a number of people in this area are proceeding in a defined way, so that
we may be able to come back aggressively into the field of small cell lung cancer
and define a role for high-dose therapy with marrow support in it.
DR. E. FREI: Well, we think that with your observations, if you can get
patients into complete remission by some kind of an induction regimen, that's
the optimal time to intensify them, maybe times two. That to me remains, along
with Dr. Symann's comparative experience, compelling evidence that you can
do something. I think Steve Wolff s program for extensive disease certainly
sounds like the way to go, but for a selected group of patients. Why do you think
patients are not being referred? Certainly nobody else has a better approach to
therapy that I'm aware of.
DR. SPITZER: There has been a lot of the negative studies of small groups
of patients in extensive disease with minimally intensive therapy, which have
recently been published with an associated number of confusing editorials.
Somehow we need to try even more strongly to define studies which may be
more convincing.
DR. LAZARUS: I might ask Dr. Symann about the monoclonal antibody
studies for the detection of tumor in the bone marrow. There have been a
number of investigators, including the National Cancer Institute group and Ruff
and Pert, who've shown that small cell lung cancer is perhaps more analogous
to a hematologic malignancy in that it shares antigens with cells like
macrophages and monocytes. In their hands and in other people's hands, the
number of surface antigens that it shared, for example, with squamous and
adeno, was less, and I just wondered about the choice. If you couldn't increase
your sensitivity by using other antibodies, then the others that you had shown
that were, 1 guess, LCA1, LCA2, and LCA3 were either derived from or reacted
with squamous cell.
DR. M. SYMANN: The antibodies I was referring to are not useful for
diagnostic purposes because they cross-react with squamous as well as with oat
cell carcinoma of the lung. Nevertheless, they do not recognize normal hematopoietic
cells. For instance, 1 didn't show the results, but in a batch of 50 normal
bone marrow samples we were completely unable to show any positive cells.
Probably, three is not enough, anyway, looking at the heterogeneity of antigenic
expression. The more we search, the more we find. Probably if we could
increase the number we could detect more positive bone marrows. Now, with
respect to the findings we may derive from that, when we looked at the bone
marrow we collected for autologous graft purposes, even if the sample was
negative on the small samples, like a 2- or 3-ml aspirate, before bone marrow