Cell-Cycle analysis
larry_seamer@bio-rad.com
Tue, 16 Sep 97 09:58:07 -0800
An Open Letter to the flow cytometry community:
I have spent a good deal of my career studying and developing flow
cytometric cell-cycle analysis. Approximately a year ago, a panel of
unnamed scientists commissioned by ASCO published a recommendation
that flow cytometry NOT be performed on breast or colorectal tumors in
a clinical setting (Journal of Clinical Oncology, 1996;14:2843-77).
Using ASCO's own statistics on papers dealing with colorectal cancer
from the last 8 years, 24 of 31 studies found ploidy to be prognostic
in colorectal cancers. In 13 of 17 studies where the question was
asked, ploidy was found to be an INDEPENDENT prognostic indicator. 4
of 7 papers found S-Phase to have prognostic significance 3 of those
determined S-Phase to be an INDEPENDENT indicator.
Their report was much more vague when reporting the outcome of the
breast cancer literature search. However the panel did note that the
majority of studies show S-Phase to have independent value in some
patient subsets. The author's complaint here was that the studies were
retrospective and used different cut-points for high vs. low S-Phase.
The panel also noted that MANY studies had found INDEPENDENT
prognostic value to S-Phase determination in axillary node negative
patients. However they expressed the same concerns as previously
noted.
Most of the findings in this report are positive and the negative
recommendation is not deserved. It is my concern that the
recommendations in this report are being taken on face value without
regard to the underlying findings of the panel. Many of the concerns
expressed can be overcome with more stringent standardization and
further prospective studies. Because of the bottom-line negative
recommendations, this report is having a chilling effect on the
oncology community, probably preventing the very studies that the
panel is looking for.
We, in the flow cytometry community, have an obligation to counter
this negative bias with sound data. It is ultimately the cancer
patient that suffers when independent prognostic information is
withheld from their clinician. I am afraid that is exactly what is
happening as a result of this report.
However, there is still time to act. First, we need to get real
standardization. Second, the Consensus Committee report from 1993
needs to be revisited and strengthened. Further, We need to talk to
oncologist to present the data that is already in the literature.
If we remain passive our potential contribution to the wellness of
these patients will go unused.