Ductal carcinoma in situ (DCIS) is the most common type of non-invasive breast cancer. Ductal means that the cancer starts inside the milk ducts, carcinoma refers to any cancer that begins in the skin or other tissues (including breast tissue) that cover or line the internal organs, and in situ means “in its original place.” DCIS is called “non-invasive” because it hasn’t spread beyond the milk duct into any normal surrounding breast tissue. DCIS isn’t life-threatening, but having DCIS can increase the risk of developing an invasive breast cancer later on.
Standard treatment options for DCIS include:
- lumpectomy followed by radiation therapy, which is the most common treatment for DCIS; lumpectomy is also called breast-conserving surgery
- mastectomy in some cases
- lumpectomy alone
- hormonal therapy after surgery if the DCIS is hormone-receptor-positive (most are)
For women who have lumpectomy to remove DCIS, the American Society of Clinical Oncology (ASCO) recommends not removing any lymph nodes unless the DCIS is large or a suspicious mass is found during lumpectomy surgery.
For women who have mastectomy to remove DCIS, ASCO recommends sentinel lymph node surgery instead of axillary node surgery. In sentinel lymph node surgery (also called sentinel node dissection or sentinel node biopsy) just the one or two lymph nodes closest to the cancer are removed and sent to a pathologist for evaluation.
In axillary node surgery, the surgeon may remove between five and 30 lymph nodes (or more) from the armpit area on the same side as the cancer during the procedure.
ASCO is a national organization of oncologists and other cancer care providers. ASCO guidelines give doctors recommendations for treatments and testing that are supported by much credible research and experience.
In the past, DCIS accounted for 1% to 2% of all breast cancer cases. Today, thanks to better sensitivity in mammograms, about 20% of breast cancer cases are DCIS.
Researchers wanted to know if the choice of surgeon and hospital affected whether ASCO lymph node removal recommendations were followed during DCIS surgery.
A study has found that surgeons who do fewer DCIS surgeries are less likely to follow the ASCO guidelines. The location of the hospital also affects the type of lymph node surgery a woman diagnosed with DCIS has.
The research was published in the June 2015 issue of JAMA Oncology. Read “The Influence of Hospital and Surgeon Factors on the Prevalence of Axillary Lymph Node Evaluation in Ductal Carcinoma In Situ.”
To do the study, the researchers looked at the records of 35,591 women who were diagnosed with DCIS and had either lumpectomy or mastectomy between January 2006 and December 2012. The women were age 18 to age 90:
- 26,580 women (74.7%) had lumpectomy
- 9,011 women (25.3%) had mastectomy
Just over half of the women (53.8%) were treated in small hospitals (hospitals with fewer than 400 beds) and 18.5% of the women were treated at large hospitals (hospitals with more than 600 beds).
The researchers also looked at how many DCIS surgeries were done at each hospital and how many DCIS surgeries each surgeon did per year:
- DCIS surgeries at hospitals ranged from 1 per year to 102 per year
- DCIS surgeries per surgeon ranged from 1 per year to 23.8 per year
The researchers classified hospitals that had fewer than 16.7 DCIS surgeries per year as low volume, between 16.7 and 38.4 procedures per year as medium volume, and more than 38.4 procedures per year as high volume.
The researchers classified surgeons that did one procedure per year as low volume, between more than one and 2.67 per year as medium volume, and more than 2.67 per year as high volume.
Most of the procedures were done by general surgeons -- only 4.7% were done by surgical oncologists.
Among the women who had mastectomy, 63% of them had some type of lymph node surgery:
- 15.2% had axillary lymph node surgery
- 47.8% had sentinel node surgery
Among the women who had lumpectomy, 17.7% had some type of lymph node surgery:
- 1.0% had axillary node surgery
- 16.7% had sentinel node surgery
Overall, rates of axillary node surgery went down and rates of sentinel node surgery went up during the time period the researchers studied:
- for women having mastectomy:
- 20.0% had axillary node surgery in 2006 and 10.7% had axillary node surgery in 2012
- 36.5% had sentinel node surgery in 2006 and 56.7% had sentinel node surgery in 2012
- for women having lumpectomy:
- 1.2% had axillary node surgery in 2006 and 0.3% had axillary node surgery in 2012
- 17.3% had sentinel node surgery in 2006 and 15.9% had sentinel node surgery in 2012
Looking at which surgeons did which procedures, the researchers found:
- low-volume surgeons did about 66% of the mastectomies and 25% of the lumpectomies
- most lumpectomies (41.9%) were done by high-volume surgeons; high-volume surgeons did only 4.9% of mastectomies
- as the number of procedures the surgeons did went up, more of the lymph node surgeries were sentinel node surgery
The researchers found that women who had mastectomy to remove DCIS were more likely to have some type of lymph node surgery if:
- they were treated at a non-teaching hospital
- they had Medicaid coverage rather than commercial insurance
- they were treated at an urban hospital
- they were treated after 2006
Women who had lumpectomy to remove DCIS were more likely to have some type of lymph node surgery if:
- they were treated at a non-teaching hospital
- they were treated by a low- or medium-volume surgeon
The bottom line is that nearly 18% of the women who had lumpectomy to remove DCIS had some type of lymph node surgery, despite ASCO recommendations against the procedure. About 15% of the women who had mastectomy had axillary node surgery, despite ASCO recommendations that sentinel node surgery be done.
Because of these relatively large numbers of procedures that go against ASCO recommendations, the researchers would like to see more studies done to figure out ways to identify women most likely to benefit from lymph node surgery. They also called for more research on other ways to evaluate whether cancer is in the lymph nodes, such as placing a marker in the node rather than removing it.
If you’ve been diagnosed with DCIS and are planning your surgery, you might want to talk to your surgeon about this study. Some questions you may want to discuss are:
- Which surgery is recommended for me and why?
- Will any lymph nodes be removed during surgery? Why or why not?
- What are the risks and benefits of each procedure recommended?
Together, you and your doctor will develop a DCIS treatment plan that is right for you and your unique situation.
For more information on lymph node surgery, visit the Lymph Node Removal pages in the Breastcancer.org Surgery section.