let's talk about DCIS of the breast patients see me all the time with the
impression that they have breast cancer DCIS is not true breast cancer I like to
explain it to women as precancerous to understand how we approach DCIS as
surgeons let's talk about the basics DCIS stands for ductal carcinoma in situ
the breast is designed to deliver milk to the nipple during pregnancy the milk
is produced in a part of the breast called the lobule and travels to the
nipple through tubes called ducts there are thousands of these duct units
throughout the breast about 80% of breast cancers come from the duct cell
whereas only 20% come from the lobules cell let's magnify one of these ducts as
the duct cells become cancerous they are stuck inside of the duct tube and when
they have not invaded through the wall of the duct they are called in-situ
only after the cancerous cells have invaded through the wall of the duct and
into the surrounding breast tissue are they considered invasive breast cancer
because there are no lymphatic channels or blood vessels inside of the ducts
DCIS cells cannot travel from the breast to lymph nodes and cannot spread they
are stuck in the duct which is why I tell women these are precancerous
because by definition the bad cells cannot get out of the breast to cause
harm how do we find DCIS well almost always it is found incidentally on
mammograms as the DCIS cells form in the ducts they grow abnormally and many
cells die as the abnormal cells die they leave calcium deposits in the ducts
which show up on the mammograms as spots of calcium radiology doctors are
especially concerned if the calcium deposits on the mammogram are new
changing or in the shape of branching ducts very occasionally a woman may have
a lump that they feel or bloody fluid coming out of their nipple that can be a
sign of DCIS cells in the breast but vast majority are found on screening
mammograms ultrasounds don't help a whole lot MRI may help once a mammogram
shows a suspicious area we always recommend starting with a needle biopsy
the abnormal area is biopsied using a mammogram machine to guide the needle in
since the calcium is easiest to see on the mammogram once the area is biopsied
we leave a small titanium marker in the exact area that was biopsied this is so
we can find the same area again in the future if the biopsy turns out to be
cancerous once a biopsy shows DCIS the first treatment is surgery there are two
types of surgery for DCIS in the breast either a lumpectomy which is removing a
portion of the breast or a mastectomy which is removing the entire breast for
a lumpectomy we usually need something as surgeons to help us know we are
removing the correct piece of tissue DCIS is usually not something you can
feel and you can't see it with your naked eye the most common way of finding
in the area is for a radiologist to place a wire through the skin with a
j-shaped hook at the end that prevents it from pulling out the tip of the wire
at the j-hook will be placed as close as possible to the clip that was left from
the needle biopsy that originally found the DCIS when the surgery is performed
the surgeon finds the wire just below the skin follows it to where the area of
the breast should be removed once we remove the portion of the breast that we
think contains the end of the wire this should contain the biopsy clip and the
bad area of DCIS and calcium we actually x-ray the piece of the breast tissue
outside the body to be sure the biopsy clip and calcium deposits are actually
in it this is called a wire localized lumpectomy
unfortunately the pathology doctors cannot tell us right away if there are
bad cells at the edge of the removed portion of the breast we usually do not
know if the edges of the tissue are clear of all DCIS for several days
because the pathology doctors need time to process the specimen we would ideally
like to have at least two millimeters of normal breast tissue surrounding the
area of bad DCIS cells DCIS tends to crawl through the duct they are growing
in and do not grow in a perfect sphere so unfortunately even in the best of
hands a lumpectomy for DCIS may have bad cells extending to the edge of the
removed tissue in about 20% of cases if the bad DCIS cells are up to the edge of
the removed tissue we call this a positive margin and we usually recommend
that we return to surgery to remove more tissue in that area called a repeat
lumpectomy now the one thing that is important to know when we offer a
lumpectomy for DCIS is that radiation to the remaining breast tissue is usually
recommended if we don't give radiation after removing a piece of DCIS we
usually say the risk of future DCIS or even invasive breast cancer is nearly
50% however if you do give radiation the chance of having DCIS or cancer regrow
is more around 10% so you need routine mammograms for follow-up usually once a
year is plenty and since the DCIS is stuck in the duct and cannot get out we
do not need to check armpit lymph nodes here the other option for surgery is a
mastectomy if a woman has a large area of DC is based on mammograms or MRI or
they have multiple areas throughout the breast or the person cannot have
radiation or does not want radiation then a mastectomy may be a good idea the
nipple can be left in place doing what we call a nipple sparing mastectomy
although I would say most of the time the nipple is removed this is because
the blood flow to the nipple may not be enough to allow the skin to stay alive
after a mastectomy or because we are worried the DCIS cells have crawled up
the duct and into the nipple itself although even though I said DCIS cannot
get into the lymph nodes sometimes when we remove the entire DCIS
area we find that apart has invasive breast cancer that the needle biopsy
missed so if we are doing a mastectomy that is our one chance to check the
lymph nodes for cancer via the sentinel lymph node biopsy technique explained in
a different video it is probably a good idea to do the lymph node check during
the mastectomy for DCIS on the small chance you find invasive cancer in the
breast after you take it out now because there is no breast tissue left after a
mastectomy there is no reason to give radiation so any mastectomy does prevent
the need for radiation with DCIS of the breast and as far as breast
reconstruction that is a topic for a different talk but suffice it to say
that reconstruction should only be an option after a mastectomy for
DCIS so after a lumpectomy for DCIS is done we let the patient heal for about
one month and then radiation is given to the remaining breast after surgery and
radiation you should see medical oncology to discuss medicine that blocks
the effects of estrogen on the breast tissue
this can help decrease the chance of DCIS regrowing or new areas of breast
cancer forming I hope this helps don't forget to subscribe below and check out
other videos I've made explaining mastectomy surgery breast biopsies and
sentinel lymph node surgery and more take care