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Educational Supplement: Appendix
Overview
of Conference
William
C. Wood, M.D., FACS
Carcinoma of
the breast remains the most common cancer in women in the United
States.
It is exceeded
only by lung cancer as a cause of cancer death in women. In the
10 years since the last NIH consensus development conference (CDC)
on this subject, large-scale randomized clinical trials have provided
further evidence regarding all types of adjuvant therapy. In order
to base consensus on clear evidence, the scope of this conference
will be limited to operable, invasive breast cancer. This is where
the survival of women with breast cancer can be significantly affected
by choice of therapy.
The questions
to be addressed by the panel meet two criteria:
They
are of crucial interest to breast cancer patients and their health
care team.
A body
of scientific evidence exists to allow an informed consensus.
A CDC in 1980
also addressed the efficacy of adjuvant chemotherapy in breast cancer
(NIH, 1980). In 1985, another CDC focused on issues of survival
and adjuvant chemotherapy and hormonal therapy (NIH, 1986). In 1990,
the question of whether breast conservation was appropriate for
primary therapy was teamed with consideration of the role of adjuvant
therapy in women without lymph node involvement (NIH, 1992). The
subsequent decade has seen trials worldwide addressing the combination
of chemotherapy with hormonal therapies, the introduction of new
cytotoxic agents of great efficacy, questions of dose and schedule,
and the evaluation of both prognostic and predictive tumor markers.
These were topics recommended for further investigation in the report
of the 1990 CDC. There now appears to be sufficient data to discuss
the question of when adjuvant therapy is appropriate and the degree
to which evidence supports tailoring the therapy to both patient
and tumor.
There are new
and promising strategies that are still a part of numerous ongoing
clinical trials. These include the mapping and evaluation of sentinel
lymph nodes to select patients for nodal staging and therapy, and
the role of immunohistochemical (IHC) evaluation of bone marrow
biopsies. Herceptin as a single agent and in combination with cytotoxic
and hormonal agents is emerging as a major subject of large-scale
clinical trials addressing schedule, duration, and optimal combination.
The role of bisphosphonates as adjuvant therapy and parameters that
may predict those patients most likely to benefit from their use
are also in the process of definition. The delayed use of chemotherapy
or hormonal adjuvant therapy and the role of maintenance
in adjuvant therapy are being studied in a few trials. At a still
earlier phase are trials of small molecule inhibitors, antisense
gene constructs, antiangiogenesis compounds, and vaccines. None
of these were judged by the planning committee to have sufficient
evidence from mature trials to be placed on the agenda at this time,
but they are worthy topics for ongoing clinical research.
References
National Institutes
of Health. Adjuvant chemotherapy of breast cancer. Consens Dev Conf
Summ 1980;3:21-4. Abstract
NIH Consensus
Development Conference Statement: Adjuvant chemotherapy for breast
cancer. September 9-11, 1985. CA Cancer J Clin 1986;36:42-7. Abstract
NIH Consensus
Development Panel. Treatment of early stage breast cancer. J Natl
Cancer Inst Monogr 1992;11:137-42. No abstract available.
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