PITTSBURGHLong-term follow-up data from National Surgical Adjuvant Breast
and Bowel Project (NSABP) trials of tamoxifen plus chemotherapy in
node-negative, estrogen receptor (ER)-positive breast cancer patients suggest
that chemotherapy does not add to the benefits of tamoxifen among women aged 60
or older. Bernard Fisher, MD, distinguished service professor at the University
of Pittsburgh and past chairman and scientific director of the NSABP, reviewed
the results of several trials, beginning with NSABP B-20. That trial
established the value of combining cyclophosphamide (Cytoxan, Neosar),
methotrexate, and fluorouracil (CMF) with tamoxifen in node-negative, estrogen
A 5-year follow-up analysis found that breast cancer risk reductions were
significantly greater among women treated with CMF plus tamoxifen (CMFT) than
among those given tamoxifen alone-46% vs 26%. At that time, the researchers
noted that these risk reductions were greater among women age 49 or younger
than among those age 50 or older.
Dr. Fisher said that with the more prolonged follow-up time, and in view of
issues recently raised about the administration of chemotherapy and tamoxifen,
the group had updated their findings and had found them compelling. With a
median follow-up of approximately 12 years, the influence of age on
chemotherapy benefit has come into sharper focus.
Analyzed by Variables
Among women aged 49 or younger and among those age 50 to 59, CMFT was
superior to tamoxifen alone for all study endpoints-disease-free survival,
relapse-free survival, distant-disease-free survival, and overall survival.
This was not true for women aged 60 or older. In this older group, CMF did not
improve upon or negate the findings from tamoxifen alone.
When the investigators analyzed the data according to menopausal status, as
reported to the NSABP data center, they found similar results. "Patients
designated as premenopausal received a remarkably good benefit from CMF plus
tamoxifen," Dr. Fisher said. CMFT offered no advantage over tamoxifen alone
among those in the postmenopausal group.
When the treatment benefits were analyzed by age or menopausal status,
neither variable affected the benefits of tamoxifen alone. But in the CMFT
patients, those who were aged 49 or younger, aged 50 to 59, or premenopausal
did much better than did those who were aged 60 or older or who were