July 22, 2005
Single drug dose effective after cancer surgery
NEW YORK (Reuters Health) - After surgery, a single dose of
carboplatin appears to be just as effective in preventing
relapse as three weeks of radiation therapy in men with
early-stage testicular cancer, according to the findings of a
study published in this week's issue of The Lancet. Carboplatin
also appears to be associated with less severe adverse effects
and lower risk of developing a tumor in the other testicle.
Although radiotherapy has long been the accepted treatment
approach, research has suggested that it may increase the risk
of later developing other types of cancer and cardiovascular
disease. Based on preliminary study findings that found one
course of carboplatin is as effective as radiation, Dr. R. T.
D. Oliver and colleagues initiated a trial comparing the two
Oliver, from St. Bart's and the London Hospital in the UK,
and colleagues included 1,477 patients with stage I testicular
cancer from 70 hospitals in 14 countries treated between 1996
and 2001. The analysis included 885 men randomly assigned to
radiotherapy and 560 to carboplatin. The subjects were followed
for an average of four years.
The relapse-free rate at three years was 95.9 percent in
the radiation group and 94.8 percent in the carboplatin group,
a nonsignificant difference. New, second primary testicular
germ-cell tumors developed in 10 patients treated with
radiation and two treated with carboplatin. One testicular
cancer-related death occurred in the radiation group.
There were no significant differences at two years in
gonadal function as measured by hormone levels. Although
adverse events were more common at 72 hours in the carboplatin
group, carboplatin was associated with less lethargy over the
next few of months and a more rapid return to work.
"This trial has shown the non-inferiority of carboplatin to
radiotherapy in the treatment of stage I seminoma," the authors
conclude. They add, "These findings need to be confirmed beyond
four years' follow-up."
In a related commentary, Drs. Padraig Warde and Mary
Gospodarowicz, from the University of Toronto, caution against
adopting carboplatin as standard follow-up treatment after
surgery for early-stage testicular cancer because surveillance
alone seems to be a safe option.
However, they add, "We do agree with Oliver and colleagues
that adjuvant carboplatin is worthy of continued study and
might be of benefit in some settings."
SOURCE: The Lancet, July 23, 2005.