About half of women diagnosed with early-stage triple-negative breast cancer who were not eligible for lumpectomy when first diagnosed became eligible for lumpectomy after chemotherapy before surgery, according to an analysis of information from a group of women who were part of a larger study.
Still, about 44% of the women who became eligible for lumpectomy ultimately decided to have mastectomy instead.
Triple-negative breast cancer is cancer that has no receptors for the hormones estrogen and progesterone, as well as no receptors for the HER2 protein. This limits the medicines that can be used to treat the cancer.
Doctors call treatments given before surgery neoadjuvant treatments.
The research was published online on Jan. 8, 2020, by JAMA Surgery. Read the abstract of “Breast Conservation After Neoadjuant Chemotherapy for Triple-Negative Breast Cancer: Surgical Results From the BrighTNess Randomized Clinical Trial.”
Mastectomy vs. lumpectomy
In many situations, people diagnosed with breast cancer can choose which type of surgery they have to remove the cancer.
- Mastectomy totally removes the breast.
- Lumpectomy, also called breast-conserving surgery, removes the cancer tumor and a rim of surrounding tissue.
Lumpectomy followed by radiation is likely to be equally as effective as mastectomy for people who have cancer in only one area of the breast and a tumor that is smaller than 4 centimeters.
In some cases, women who’ve been diagnosed with early-stage breast cancer in one breast choose to have that breast and the other healthy breast removed — a double mastectomy. Removing the other healthy breast is called contralateral prophylactic mastectomy.
The healthy breast usually is removed because of an understandable fear that a new, second breast cancer might develop in that breast. More and more women in the United States who’ve been diagnosed are opting for contralateral prophylactic mastectomy — in the late 1990s, between 4% and 6% of women who were having mastectomy decided to have the other healthy breast removed. From 2002 to 2012, contralateral prophylactic mastectomy rates rose from 3.9% to 12.7%. So the rate, while still relatively low, more than tripled in that time period.
There are benefits and risks that come with each type of surgery for anyone diagnosed with breast cancer. Still, women in particular may want to consider the following factors when making decisions about breast cancer surgery:
- Do you want to keep your breast?
- Do you want your breasts to match as much as possible in size?
- How anxious will you be about the breast cancer coming back?
- Do you want to have reconstruction? Radiation may affect the timing of reconstruction and possibly reconstruction options.
- Mastectomy is more extensive surgery than lumpectomy, and double mastectomy is more extensive than single mastectomy.
About the study
Called the BrighTNess trial, this study was designed to see if adding the PARP inhibitor veliparib to the chemotherapy medicines paclitaxel (brand name: Taxol) and/or carboplatin before surgery for early-stage triple-negative breast cancer would improve pathological complete response rates.
The PARP enzyme fixes DNA damage in both healthy and cancer cells. PARP inhibitors have been shown to work against breast cancer with a BRCA1 or BRCA2 mutation by making it very difficult for these cancer cells to fix DNA damage.
One way doctors judge the effectiveness of neoadjuvant chemotherapy is to look at the tissue removed during surgery to see if any actively growing cancer cells are present. If no active cancer cells are present, doctors call it a “pathologic complete response” or pCR.
The study included 634 women age 22 to 78 diagnosed with stage II to stage III triple-negative breast cancer. The women lived in 15 countries in North America, Europe, and Asia.
The women were randomly assigned to one of three neoadjuvant treatment groups:
- 12 weeks of weekly paclitaxel
- 12 weeks of weekly paclitaxel and carboplatin
- 12 weeks of weekly paclitaxel, carboplatin, and veliparib
Before the women started neoadjuvant chemotherapy, their doctors decided if they were eligible for lumpectomy.
The first analysis of the study found that adding veliparib to paclitaxel and/or carboplatin did not improve pCR rates.
This second analysis looked at the women’s surgery choices and whether lumpectomy eligibility was linked to pCR.
For this analysis on surgery choices, the researchers had information on 604 women.
Before the women started neoadjuvant chemotherapy, 141 women were not eligible for lumpectomy.
Of these 141 women, 75 (53.2%) were considered eligible for lumpectomy after neoadjuvant chemotherapy.
Overall, 342 (68.1%) of 502 women eligible for lumpectomy after neoadjuvant chemotherapy actually had lumpectomy, including 42 of the 75 women who became eligible for lumpectomy after chemotherapy.
Women who were treated in Europe and Asia were more likely to have lumpectomy than women treated in North America.
Among women who did not have a mutation in the BRCA1 or BRCA2 genes, women treated in North America were more likely to undergo contralateral prophylactic mastectomy than women treated in Europe or Asia.
Women who have a BRCA1 or BRCA2 mutation (or both) can have up to a 72% risk of being diagnosed with breast cancer during their lifetimes. Breast cancers associated with a BRCA1 or BRCA2 mutation tend to develop in younger women and occur more often in both breasts than cancers in women without these genetic mutations.
pCR rates were similar between women who were eligible for lumpectomy before chemotherapy and women who became eligible for lumpectomy after chemotherapy.
"Surgical results from the BrighTNess trial demonstrate that neoadjuvant chemotherapy makes breast conservation possible in half of patients with stages II to III [triple-negative breast cancer] who would have otherwise required mastectomy, increasing the overall percentage of those eligible for [lumpectomy] from 76.5% at diagnosis to 83.8% after [neoadjuvant systemic therapy]," the authors wrote. "However, only two-thirds of those eligible for breast conservation opted for this surgical approach.
"In BrighTNess, many [lumpectomy]-eligible women — including 114 (26.0%) of those with negative test results for a deleterious …BRCA mutation — still underwent mastectomy," they continued.
What this means for you
When you’re first diagnosed with breast cancer, fears about the future can affect how you make decisions. You have to make a number of decisions at a very emotional time when it can be hard to absorb and understand all the new information you’re being given.
At Breastancer.org, we support everyone’s right to make treatment decisions based on the characteristics of the cancer you’ve been diagnosed with, your medical history, your risk of recurrence or a new breast cancer, and your personal preferences. But it’s very important to make sure you understand all the pros and cons of any treatment or procedure you’re considering, including how the treatment or procedure may affect your reconstruction options and if the treatment is likely to make you live longer.
If you’ve been diagnosed with early-stage breast cancer, ask your doctor about all of your treatment and risk reduction options. Mastectomy and contralateral prophylactic mastectomy are more aggressive options than lumpectomy. While mastectomy or contralateral prophylactic mastectomy may be the right decision for you, give yourself the time you need to consider the decision carefully. It’s a good idea to talk to your doctor about how the details in your pathology report may affect your future risk. You want to be sure that your decisions are based on your actual risk of recurrence or a new cancer. Make sure you understand the benefits and risks of all your options. Together, you and your doctor can make the choices that are best for you and your unique situation.
For more information on the advantages and disadvantages of both types of breast cancer surgery, visit the Breastcancer.org Mastectomy vs. Lumpectomy page.
To talk with others about making surgery decisions, join the Breastcancer.org Discussion Board forum Surgery - Before, During, and After.
Written by: Jamie DePolo, senior editor
Reviewed by: Brian Wojciechowski, M.D., medical advisor