The large study reviewed here found that the number of women who decided to have both breasts removed after being diagnosed with DCIS (ductal carcinoma in situ) in one breast more than tripled between 1998 and 2005.
Removing a breast that has no cancer in it is known as a prophylactic mastectomy. Removing both breasts is called double or bilateral mastectomy.
In an earlier study, the same researchers found a similar increase in the number of women choosing to have bilateral mastectomies after being diagnosed with invasive breast cancer in one breast.
In the study reviewed here, the researchers looked at the medical records of more than 51,000 women diagnosed and treated for DCIS from 1998 to 2005. The likelihood that a woman would decide to have prophylactic mastectomy on the other healthy breast increased during the time studied:
Women diagnosed with DCIS have a very good prognosis. Ten years after DCIS diagnosis, 98% to 99% of women will be alive. Based on this good prognosis, DCIS usually is treated by lumpectomy followed by radiation therapy. If the DCIS is large, a mastectomy may be recommended. Removing the opposite breast usually isn't recommended; chemotherapy usually isn't recommended either. Hormonal therapy may be recommended if the DCIS is hormone-receptor-positive.
DCIS is NOT invasive cancer. DCIS stays inside the breast milk duct. DCIS can be large or small, but it does NOT spread outside the milk duct into the surrounding normal breast tissue or into the lymph nodes or other organs. Still, if you've been diagnosed with DCIS, you're at higher risk of developing invasive breast cancer in that breast than someone who hasn't had DCIS. DCIS also is referred to as stage 0 breast cancer.
After a DCIS diagnosis in one breast, the average risk of developing either DCIS or invasive breast cancer in the OPPOSITE breast is small -- under 1% each year. The risk is higher for women who have an abnormal breast cancer gene (BRCA1 or BRCA2). Choosing to have both breasts removed after a DCIS diagnosis in one breast is very aggressive treatment. Yes, it does make it very unlikely that any type of breast cancer will be diagnosed again. Still, for women with no abnormal breast cancer genes, prophylactic mastectomy probably doesn't improve the excellent prognosis that comes with more conservative treatment approaches.
This study didn't ask why more women diagnosed with DCIS are choosing to have double mastectomy. But it's likely that the women are worried about developing breast cancer again in the future, in either the same breast where DCIS was found, or in the opposite breast. The study showed that younger women diagnosed with DCIS chose double mastectomy more than older women. This may be because younger women have more time ahead of them to possibly develop a second breast cancer. Reconstruction choices also may play a role in more women opting for double mastectomy. Women who chose mastectomy as the first treatment for DCIS also were more likely to have prophylactic mastectomy of the opposite breast, compared to women who chose lumpectomy as the first treatment for DCIS. Women may have chosen mastectomy because the DCIS was large, because of family history, or because they wanted to take a very aggressive treatment approach.
Every woman's situation is unique and every woman diagnosed with breast cancer, whether it's DCIS or invasive, has to ask herself this question: How much risk of the cancer coming back or a new cancer being diagnosed can I personally tolerate? Everyone will have a different answer to the question and the answer will affect how aggressive you want to be with treatment.
If you've been diagnosed with DCIS and are considering double mastectomy to reduce future risk, here are some things to consider:
What's your actual risk of developing a second breast cancer after treatment for DCIS?
It's important to talk about this with your doctor. Many women tend to overestimate their risk of breast cancer. This may be an unintended effect of great awareness of breast cancer. Before making any decisions about surgery, it's a good idea to figure out the risk associated with your unique situation.
What are your plans, if any, for breast reconstruction after surgery?
To achieve a balanced appearance, some women may need or want cosmetic surgery on the healthy breast after reconstruction. Also, some types of reconstruction can be done only once, which may limit reconstruction options for women who may need a second mastectomy if breast cancer is diagnosed later in the other breast. So some women may choose to have a double mastectomy and reconstruct both breasts at the same time. Your medical team, including a plastic surgeon, can help you make the best choice for you.
Do you have an abnormal BRCA1 or BRCA2 gene?
Some women may assume they have an abnormal breast cancer gene because someone in the family had breast cancer -- without ever having genetic testing and counseling themselves. Having an abnormal BRCA1 or BRCA2 gene has a big influence on the risk of developing breast cancer and on breast cancer coming back. If you're considering a double mastectomy because you MIGHT have an abnormal gene based on family history, talk to your doctor about whether genetic testing and counseling make sense for you. You may still decide to have a double mastectomy, but it's better to make the decision based on facts, not assumptions.
Can medicine lower my risk of developing breast cancer?
Removing a healthy breast essentially eliminates the possibility of breast cancer in that breast. Medicines that lower the risk of breast cancer don't offer the same certainty, but they may be another option to consider.
If you've been diagnosed with DCIS, talk to your medical team about ALL your treatment options so you can make the best decisions for YOU and your unique situation.
HOUSTON, April 10 (MedPage Today) -- Women with ductal carcinoma (DCIS) in situ in one breast have increasingly undergone bilateral mastectomy despite a minimal likelihood of improved survival, according to a national cancer database.
The rate of double mastectomy increased from 4.1% of women with DCIS in 1998 to 13.5% in 2005, Todd M. Tuttle, M.D., of the University of Minnesota in Minneapolis, and colleagues reported online in the Journal of Clinical Oncology.
In addition, the rate tripled among those women who opted for mastectomy as primary treatment for DCIS.
The findings mirror those from an earlier study by the same group, showing a two- to threefold increase in contralateral prophylactic mastectomy in women with unilateral breast cancer, regardless of the primary treatment.
"The 10-year survival rate for women with DCIS is 98% to 99%," Dr. Tuttle said in a statement. "Therefore, removal of the normal contralateral breast will not improve the excellent survival rates for this group of women. Nevertheless, many women, particularly young women, are choosing to have both breasts removed."
Women with unilateral DCIS have a 0.6% annual risk of developing invasive breast or DCIS in the opposite breast. Because of the low mortality risk, the rate of contralateral prophylactic mastectomy has substantial clinical relevance, the authors said.
Two years ago, Dr. Tuttle documented an increased frequency of contralateral prophylactic mastectomy among women with unilateral invasive breast cancer. However, the frequency of prophylactic breast removal associated with DCIS had not been determined.
For the current study, the authors queried the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) database for the years 1998 through 2005. The analysis included 16 geographic areas comprising about a quarter of the U.S. population.
The analysis identified 51,030 patients with DCIS, 2,072 of whom had contralateral prophylactic mastectomy. The rate of prophylactic breast removal was 4.1% for all surgically treated patients, including those who had breast-conserving surgery, and 13.5% among patients who chose mastectomy for DCIS.
Limiting the analysis to the subgroup of patients who had mastectomy for DCIS, the authors found that the rate of contralateral prophylactic mastectomy increased by 188% from 1998 to 2005 (6.4% versus 18.4%). Among all surgically treated patients, the rate of prophylactic breast removal increased by 148% (2.1% to 5.2%).
By logistic regression analysis, factors that increased the likelihood of contralateral prophylactic mastectomy were younger age, white race, more recent year of diagnosis, and the presence of lobular carcinoma in situ.
Dr. Tuttle and colleagues pointed to the apparent contradictions in women's approaches to DCIS.
"Despite having a low breast cancer mortality rate, women with DCIS are increasingly undergoing contralateral prophylactic mastectomy," they said. "At the same time, more women with DCIS are undergoing breast-conserving surgery and fewer are undergoing unilateral mastectomy."
They said additional studies to evaluate the "complex decision-making process leading to" prophylactic mastectomy were a critical need.
Limitations cited by the authors included lack of detail in data from the SEER registry, failure to identify women who opted for contralateral mastectomy more than six months after initial treatment, and lack of surgical codes to identify women who had breast-conserving surgery for one breast and mastectomy for the other.
No external funding for the study was reported.
The authors reported no potential conflicts of interest.
Primary source: Journal of Clinical Oncology Source reference: Tuttle TM et al. "Increasing rates of contralateral prophylactic mastectomy among patients with ductal carcinoma in situ" J Clin Oncol 2009; 27(9): 1362-1367.
Breastcancer.org 7 East Lancaster Avenue, 3rd Floor Ardmore, PA 19003
Learn more about our commitment to your privacy
© 2009 Breastcancer.org - All rights reserved.
Breastcancer.org is a non-profit organization dedicated to providing information and community to those touched by this disease. Learn more about our commitment to providing complete, accurate, and private breast cancer information.
_tcm8-332386.jpg "wellness_dvd_promo")