Lack of Proof from Randomized Trials for the
Superiority of Platinum Combinations Over Single Agent Alkylators
The Advanced Ovarian Trialists Group has published
a series of landmark meta-analyses which have summarized the overall conclusions
from prospective, randomized trials in ovarian cancer. In their 1991
publication, entitled "Chemotherapy in advanced ovarian cancer; an
overview of randomized clinical trials" (Br Med J 303:884-893,'91)
they concluded that (I quote) "no conclusions could be made."
Which is to say that nothing had ever been proven to be better than
anything else, save for the equivalency of cisplatin and carboplatin, with
regard to long term survival. In their most recent update (Br J Cancer
78:1479-1487,'98) they did not present their updates on the studies of
platinum combinations versus single agent alkylators, but stated that the
data were available upon request (from Dr. L. Stewart, Head, Meta-analysis
group, MRC Clinical Trials Unit, 222 Euston Road, London, NW1 2DA, UK.
e-mail: ls@ctu.mrc.ac.uk).
I wrote to Dr. Stewart and received several pages of data, showing no difference
between the survival curves between patients treated
initially with platinum combinations versus single agent alkylators, nor
any difference between hazard ratios between platinum combination therapy
versus single agent alkylators (HR = 0.934, 95% confidence interval 0.831
to 1.049, p = 0.246).
And yet THREE different review papers (plus the lecture to which a link
was provided) maintain that the superiority for intial therapy with platinum
combinations has been proven! Quoting the studies of the Advanced
Ovarian Trialists Group! I don't think so. Show me the data.