Here's some interesting info on neurotoxicity associated with high dose chemotherapy treatment of breast cancer:
Efficacy, Toxicity Of High-Dose Chemo In Breast
Cancer Requires Further Study
WESTPORT, Feb 04 (Reuters) - Use of high-dose
chemotherapy with autologous stem-cell rescue as a
standard therapy for breast cancer is on the rise, but
selection of this protocol may be premature, according to
two reports out today in the February 4th issue of the
Journal of the National Cancer Institute.
In the first report, Dr. JoAnne Zujewski and colleagues at
the National Cancer Institute in Bethesda, Maryland, show
that the available clinical data are insufficient to support
high-dose chemotherapy with stem-cell rescue as a
treatment for breast cancer. The NCI team reviewed the
literature on trials that were conducted between January
1966, and May, 1997.
They found more than 600 English-language papers on the
topic, including a number of preclinical, Phase I/II, Phase II,
and pilot studies, but there was only one randomized Phase
III trial comparing high-dose chemotherapy with stem-cell
rescue with more conventional chemotherapy.
The results of the latter trial were promising, and
demonstrated a significantly increased survival rate for
women treated with the high-dose regimen compared with
those given conventional chemotherapy. But Dr. Zujewski
and her associates write that the randomized trial was small
and pointed out that the survival rate for women treated with
conventional chemotherapy was lower in this study than
would be expected.
Overall, Dr. Zujewski and her team report that the data are
"inconclusive," but that the results from ongoing, large,
randomized trials should clarify the role of high-dose
chemotherapy with autologous stem-cell rescue in the
treatment of breast cancer.
In a telephone interview with Reuters Health, Dr. Zujewski
urged physicians and the public to "...have a trust in the
clinical trials process and to enroll in clinical trials...[because]
only through these trials will we be able to provide women
with the answers that they really need to make decisions."
Once all the cards are on the table, this therapy "...is likely to
make a contribution to breast cancer treatment," the team
writes in the paper.
Elsewhere in the journal, researchers in The Netherlands
warn that neurologic toxicity may be a limiting factor in use
of high-dose chemotherapy in breast cancer. In response to
complaints of persistent cognitive defects in breast cancer
patients following chemotherapy, Dr. Frits S.A.M. van Dam
of The Netherlands Cancer Institute in Amsterdam and a
multicenter team examined cognitive functioning before and
after treatment in a group of breast cancer patients who
received high-dose chemotherapy plus tamoxifen,
standard-dose chemotherapy plus tamoxifen or no
chemotherapy.
The Dutch team found that "...the patients treated with
high-dose chemotherapy had an 8.2-times higher risk of
cognitive impairment than the control patients who were not
treated with systemic therapy and a 3.5-times elevated risk
in comparison with the patients who were treated with
standard-dose chemotherapy."
"On the basis of [these] findings, which are indicative of
neurotoxicity caused by systemic chemotherapy in adult
patients," Dr. van Dam and colleagues "...believe that central
neurotoxicity might become a dose-limiting factor in
high-dose chemotherapy regimens." They point out that
these effects should be further explored before high-dose
regimens are introduced into routine clinical practice.
Elsewhere in the journal, Dr. Patricia A Ganz of the
University of California at Los Angeles agrees with Dr. van
Dam's final conclusion, pointing out that researchers should
"...push for systematic research on the late effects of cancer
treatment." She adds that, though survival may be the
number one priority for breast cancer patients in choosing a
course of treatment, "...they are also concerned about the
quality of their survival."
J Natl Cancer Inst 1998;90:182-183,200-218.
-Westport Newsroom 203 319 2700 |
