With an earlier diagnosis of breast cancer some patients do not need chemotherapy
because of their excellent prognosis. These patients may need only local
therapy, such as mastectomy or lumpectomy and radiotherapy or may need
local therapy plus hormone therapy. In patients who need chemotherapy,
that chemotherapy will clearly increase the time they are free from cancer
and decrease their chance of recurrence.
The need for chemotherapy is based on multiple tumor and patient factors.
These factors include age, menopausal status, nodal status, hormone receptors
and the HER2-neu gene analysis of the tumor. Most node positive patients
will benefit from the addition of chemotherapy and many higher risk node
negative patients will also benefit from chemotherapy. Newer tests in
node negative patients, such as the gene based Oncotype DX assay, help
select which node negative patients are higher risk and may benefit from
chemotherapy. After all of these factors have been considered, some patients
will have a great benefit with the addition of chemotherapy and some will
have only a modest benefit. At that point, discussion between the patient
and the physician will help to determine what risk and toxicity the patient
is willing to accept for what level of benefit.
A current concept in the chemotherapy of breast cancer at the time of diagnosis
is called neoadjuvant chemotherapy. This is a treatment regimen that involves
giving chemotherapy prior to surgery. There are two goals: 1) converting
those patients who would initially need a mastectomy to being able to
have breast conserving treatment with lumpectomy and radiation therapy,
and 2) evaluating the effect of chemotherapy on reducing or eliminating
the cancer. Chemotherapy may be given either before or after surgical
treatment with identical cure rates.
This treatment chemotherapy is given after surgery. Most drug combinations
in the adjuvant therapy of breast cancer include such drugs as Adriamycin,
Cytoxan, Taxol, and Taxotere. These chemotherapy regimens in general,
over the past several years, have become more aggressive and shorter in
length and have less toxicity compared to older regimens. This is because
better anti-nausea drugs are available and drugs such as Neulasta are
given to maintain normal blood count and thus greatly decrease the chance
of infectious complications, which used to be a major problem with chemotherapy.
In the special circumstance of tumors that over-express the HER2-neu gene,
the addition of Herceptin has greatly improved the cure rate in these
more aggressive tumors. The addition of Herceptin in the adjuvant treatment
of breast cancer has been one of the major advances in breast cancer therapy
in the last five years.
Breast cancer is said to have metastasized if it has spread beyond the
area of the breast, either to the axillary lymph nodes or into other parts
of the body (liver, lung, bone). In patients whose tumors are hormone
receptor positive, multiple anti-hormonal modalities of therapy would
be exhausted before proceeding to chemotherapy. There are a multitude
of drugs that are used in metastatic breast cancer with the goal to prolong
life with minimal toxicity.