Treatment of invasive breast cancer, by stage

Treatment of invasive breast cancer, by stage

Breast-conserving surgery (BCS) is often appropriate for earlier-stage invasive breast
cancers if the cancer is small enough, although mastectomy is also an option. If the
cancer is too large, a mastectomy will be needed, unless pre-operative (neoadjuvant)
chemotherapy (chemo) can shrink the tumor enough to allow BCS. In either case, one or
more underarm lymph nodes will need to be checked for cancer. Radiation will be needed
for almost all patients who have BCS and some who have mastectomy. Adjuvant
systemic therapy after surgery is typically recommended for all cancers larger than 1 cm
(about 1/2 inch) across, and also sometimes for smaller tumors.
Stage I
These cancers are still relatively small and either have not spread to the lymph nodes
(N0) or have a tiny area of cancer spread in the sentinel lymph node (N1mi).
Local therapy: Stage I cancers can be treated with either BCS (lumpectomy, partial
mastectomy) or mastectomy. The lymph nodes will also need to be evaluated, with a
sentinel lymph node biopsy or an axillary lymph node dissection. Breast reconstruction
can be done either at the same time as surgery or later.
Radiation therapy is usually given after BCS. Women may consider BCS without
radiation therapy if ALL of the following are true:
· They are age 70 years or older.
· The tumor was 2 cm or less across and it has been completely removed.
· The tumor contains hormone receptors and hormone therapy is given.
· None of the lymph nodes that were removed contained cancer.
Some women who do not meet these criteria may be tempted to avoid radiation, but
studies have shown that not getting radiation increases the chances of the cancer coming
back.
Adjuvant systemic therapy: Most doctors will discuss the pros and cons of adjuvant
hormone therapy (either tamoxifen, an aromatase inhibitor, or one following the other)
with all women who have a hormone receptor–positive (estrogen or progesterone) breast
cancer, no matter how small the tumor. Women with tumors larger than 0.5 cm (about 1/4
inch) across may be more likely to benefit from it.
If the tumor is smaller than 1 cm (about 1/2 inch) across, adjuvant chemo is not usually
offered. Some doctors may suggest chemo if a cancer smaller than 1 cm has any
unfavorable features (such as being high-grade, hormone receptor–negative, HER2-
positive, or having a high score on one of the gene panels like Oncotype Dx). Adjuvant
chemo is usually recommended for larger tumors.
For HER2-positive cancers, adjuvant trastuzumab (Herceptin) is usually recommended as
well.
See below for more information on adjuvant therapy.

Stage II
These cancers are larger and/or have spread to a few nearby lymph nodes.
Local therapy: Surgery and radiation therapy options for stage II tumors are similar to
those for stage I tumors, except that for stage II, radiation therapy to the chest wall may
be considered even after mastectomy if the tumor is large (more than 5 cm across) or
cancer cells are found in several lymph nodes.
Adjuvant systemic therapy: Adjuvant systemic therapy is recommended for women
with stage II breast cancer. It may involve hormone therapy, chemo, trastuzumab, or
some combination of these, depending on the patient's age, estrogen-receptor status, and
HER2/neu status. See the following section for more information on adjuvant therapy.
Neoadjuvant therapy: An option for some women who would like to have BCS, but the
surgeon thinks the tumor is too large to have a good result, is to have neoadjuvant (before
surgery) chemo, hormone therapy, and/or trastuzumab to shrink the tumor.
If the neoadjuvant treatment shrinks the tumor enough, women may then be able to have
BCS (such as lumpectomy) followed by radiation therapy. More adjuvant therapy after
surgery may also be given.
If the tumor does not shrink enough for BCS, then mastectomy may be required.
Adjuvant therapy may also be given after surgery, but would likely be with different
drugs, since the tumor did not shrink with the first set given. Radiation therapy may be
given after surgery, as well.
A woman's chance for survival from breast cancer does not seem to be affected by
whether she gets chemo before or after her breast surgery.
Stage III
For a cancer to be a stage III, the tumor must be large (greater than 5 cm or about 2
inches across) or growing into nearby tissues (the skin over the breast or the muscle
underneath), or the cancer has spread to many nearby lymph nodes. Local treatment for
some stage III breast cancers is largely the same as that for stage II breast cancers.
Tumors that are small enough (and have not grown into nearby tissues) may be removed
by BCS (such as lumpectomy) which is followed by radiation therapy. Otherwise, the
breast is treated with mastectomy (with or without breast reconstruction). Sentinel lymph
node biopsy may be an option for some patients, but most require an axillary lymph node
dissection. Surgery is usually followed by adjuvant systemic chemotherapy, and/or
hormone therapy, and/or trastuzumab. Radiation after mastectomy is often recommended.
Often, stage III cancers are treated with neoadjuvant chemo (chemo before surgery). This
may shrink the tumor enough that BCS may be done. Otherwise, a mastectomy is done.
Usually an axillary lymph node dissection is done as well. Immediate reconstruction may

be an option for some, but reconstruction is often delayed until after radiation therapy,
which is often given even if a mastectomy is done. Adjuvant chemo may also be given,
and adjuvant hormone therapy is offered to all women with hormone receptor–positive
breast cancers.
Some inflammatory breast cancers are stage III. They are treated with neoadjuvant
chemo, sometimes with radiation. This is followed by a mastectomy and axillary lymph
node dissection. Then adjuvant treatment with chemo (and trastuzumab if the cancer is
HER2-positive), radiation therapy (if it wasn’t given before surgery), and hormone
therapy (if the cancer is hormone receptor−positive) is given.