NCCN Guidelines for Patients
Breast Cancer - Carcinoma in Situ
, Version 1.2016
Breast cancer treatment
Only a small group of women with DCIS are able
to have a lumpectomy without any other cancer
treatment. These women are very unlikely to have the
breast cancer return after surgery because the extent
of DCIS is so small. Your doctor will assess if the
cancer is likely to return. Breast cancer is less likely to
return if you are older than 50 years of age, the tumor
is small and low grade (grade I), and the surgical
margins are large and cancer-free. Talk with your
doctor about how likely it is the cancer will return so
that you can decide together if a lumpectomy alone is
the best treatment.
Before the lumpectomy, you will be asked to stop
eating, drinking, and taking some medicines for a
short period of time. If you smoke, it is important to
stop. Pain is prevented with either local or general
anesthesia. Often, breast tissue is removed through
a C-shaped cut. A lumpectomy is finished within 15 to
40 minutes. Afterward, a tube may be placed in your
breast to drain fluid.
A lumpectomy will leave a small scar and may cause
some pain and swelling for about a week. It may
also cause a dent in your breast that can be fixed
with breast reconstruction. Breast reconstruction is
described later in this chapter. Ask your treatment
team for a complete list of side effects of lumptectomy.
The tissue from the lumpectomy will be tested by a
pathologist for cancer cells at or near the margin.
You also may be given another mammogram to look
for any cancer that wasn’t removed. If it appears
that cancer remains in your breast, more surgery
is needed. The second surgery is often another
lumpectomy but sometimes a mastectomy is needed.
Lumpectomy and radiation therapy
A lumpectomy followed by radiation therapy is called
breast-conserving therapy. It is an option for many
but not all women with DCIS. Radiation therapy uses
high-energy rays to treat cancer. The rays damage
the genes in cells. This either kills the cancer cells
or stops new cancer cells from being made. Adding
radiation therapy has been shown to help stop the
return of cancer within the breast. It is given only after
cancer-free surgical margins have been removed.
Radiation therapy overview
Most of your breast will be treated with radiation.
This is called whole breast radiation. Recently, some
doctors have given radiation only to the lumpectomy
site instead of giving whole breast radiation. Radiation
only to the lumpectomy site is called partial breast
irradiation. If you’re interested in this treatment,
NCCN experts advise that you receive it only within
a clinical trial. A clinical trial is a type of research that
studies a test or treatment.
The most common type of radiation therapy used
for breast cancer is EBRT (
herapy). This type of therapy uses a machine outside
the body to deliver radiation. 3-D machines deliver
beams matched to the shape of the tumor. IMRT
herapy) uses small
radiation beams of different strengths based on the
thickness of the tissue.
A planning (simulation) session is needed before
treatment. During simulation, pictures of the tumor
site should be made with CT (
A CT scan takes many x-rays of the breast from
different angles. Your doctors will use the pictures to
decide the radiation dose and to shape the radiation
beams. Beams are shaped with computer software
and hardware added to the radiation machine. The
beams are shaped so that normal tissue is spared.
Radiation beams will be aimed at the tumor site with
help from ink marks or tiny tattoos on your skin.