Although HER2-positive breast cancer is an aggressive type of the disease, recent advances in medicine have dramatically improved treatment outcomes. Compared to simply a number of a long time ago, this sort of breast cancer responds higher to treatment. Yet, victims still select a mastectomy over surgery that will allow them to maintain their breasts—and researchers aren't sure why.
“Perhaps it's because people with HER2-positive breast cancer are really concerned and believe that mastectomy will lead to better outcomes, when in reality it doesn't improve survival for most people,” says Marisa Weiss, MD, chief medical officer of Breastcancer.org.
“This study shows that patients make their decision to have a mastectomy based on the disease subtype, i.e. HER2 status, which is not a reason for a mastectomy,” says Weiss.
HER2-positive is only one phenotype or subtype of breast cancer. About 20% of all breast cancer diagnoses are HER2-positive. With early diagnosis and treatment with chemotherapy and antibody therapy, the possibility of survival is over 90%.
“The recommendation for mastectomy depends more on the extent of the disease than on the phenotype,” says Weiss.
Researchers presenting data on the 2023 American Society of Clinical Oncology meeting are unsure why individuals with HER2-positive breast cancer prefer mastectomy to breast-conserving surgery (BCS).
During a mastectomy, all the breast is removed. If needed, it might probably then be reconstructed by a plastic surgeon.
During a BCS or lumpectomy, the doctor removes the cancer and leaves the remaining of the breast intact. They may remove some lymph nodes to see if the cancer has spread. If you could have a lumpectomy, you'll most probably have radiation afterward.
Choosing lumpectomy and radiation as a substitute of mastectomy doesn't affect your probabilities of survival. In fact, for ladies with early-stage breast cancer, survival rates are higher with lumpectomy than with mastectomy.
The scientists checked out tumor types and whether people selected a mastectomy or BCS. Of greater than 543,000 people between 2010 and 2019, nearly 32% of patients had a mastectomy and about 68% had BCS. The researchers didn't have a look at data from people whose cancer had spread to other areas of the body. They checked out points similar to tumor size and what stage the disease was at.
The researchers tried to pick those that were candidates for mastectomy or breast-conserving surgery. In other words, most of them must have had the liberty to decide on which surgery they wanted, says Matthew Lewis Pierotti, MD, a breast surgery oncology resident at Fox Chase Cancer Center who led the study.
The study investigated surgical options in patients with three breast cancer subtypes: hormone receptor (HR), HER2-positive and triple negative (TN) tumors.
If the tumor is HR-positive, it means it grows due to the hormones estrogen or progesterone. Doctors treat HR-positive breast cancer with drugs that focus on a selected hormone.
HER2-positive breast cancer gets its name when your body produces an excessive amount of human epidermal growth factor receptor 2 (HER2) protein. These tumors are inclined to grow faster and are available back. Instead of giving hormone-based treatments, doctors must attack the HER2. In recent years, newer treatments have come onto the market which have greatly improved outcomes.
Triple negative (TN) tumors are harder to treat because they shouldn't have hormone or HER2 receptors. They recur more often and are more aggressive than HR- or HER-positive breast cancers.
In the study, researchers found that girls with HER2-positive breast cancer were 1.39 times more prone to undergo mastectomy than women with HR-positive cancer. However, there was no major difference in women who underwent mastectomy whether or not they had HR-positive or TN cancer.
People who're candidates for BCS may decide to have a mastectomy for quite a lot of reasons. Some may not need to undergo radiation therapy, others may desire a more symmetrical appearance. Others could also be afraid that the cancer may return and think that breast removal is one of the best solution.
Some evidence suggests that patients with early-stage breast cancer decide to have a mastectomy because they know that breast reconstruction is feasible.
In some cases, a mastectomy is one of the best solution, but this often will depend on aspects similar to tumor size, variety of tumors and former breast cancer.
The decision to have a mastectomy is “complex and multifaceted,” says Dr. Mehra Golshan, clinical director of the Breast Cancer Center at Smilow Cancer Hospital and Yale Cancer Center. It requires shared decision-making between patient and doctor, says Golshan, who was not involved within the study.
“There are some women who absolutely need to have a mastectomy, but for most, both surgeries are possible,” says Golshan.
Todd M. Tuttle, MD, a professor of surgery on the University of Minnesota who was not a part of the study team, says with the ability to see differences in mastectomy rates by breast cancer type would shed more light on whether or not mastectomies are significantly more common in HER2-positive breast cancer.
Researchers must look beyond the info to grasp why individuals with HER2-positive breast cancer could also be more prone to select mastectomy, says Dr. Laura S. Dominici, division chief of breast surgery at Brigham and Women's Faulkner Hospital in Massachusetts, who reviewed the study abstract.
They need to review the precise characteristics of HER2-positive cancers to know whether women are less prone to be candidates for lumpectomy, Dominici says.
Golshan believes one reason individuals with HER2-positive breast cancer usually tend to select mastectomy over BCS is because their disease is commonly more advanced. However, many doctors typically treat the tumor with drug therapy before surgery, Golshan says.
Researchers should investigate which aspects influence the choice to have a mastectomy, says Dominici.
“This level of information cannot be obtained through … data, so more work is needed to answer this question,” Dominici says. The study raises questions that have to be answered in future research, she says.
“More work is needed to understand why the numbers are higher in this group,” Golshan says.
Like the study authors, Dominici says mastectomy rates are mostly declining. Rates of each mastectomies began rising in 2008, then declined around 2013 and stabilized after that. More recent data show they declined between 2013 and 2020 amongst women under 40, a report said.
According to a different report, women who're candidates for breast augmentation are increasingly choosing complete breast removal.
Recent data show that mastectomy is commonest in patients with stage III cancer in comparison with other stages.
Some patients with cancer in a single breast decide to have the unaffected breast removed at the identical time. This procedure increased from 10% to 33% amongst women aged 20 to 44 between 2004 and 2012. Among women over 45, it increased from 4% to 10% over the identical period.
Pierotti says more people have to be informed about HER2-positive breast cancer tumors and their treatment.
He plans to further study how these data correspond with mastectomy trends amongst people covered by government medical health insurance through the Department of Defense, including energetic military personnel, retirees and their families.
“We are trying to find out whether there are patient characteristics or peculiarities of the cancer that provide information about whether people should undergo surgery,” he explains.
Pierotti agrees that they should not sure why people decide to have a mastectomy. Breast reconstruction options have improved and a few people could also be influenced by celebrities, he says.
A study found that girls who decide to have a mastectomy are inclined to be younger, have higher levels of education and have higher insurance. In some cases, they decide to have the mastectomy because they're afraid the cancer will come back, the study authors say.
“We need to educate patients about the pros and cons so they can make the right decision for them,” says Pierotti. “Patients have two options, and both are equally good in terms of survival.”
The need for more aggressive systemic therapies, similar to chemotherapy and anti-HER2 therapies, doesn't mean that more aggressive local treatment, similar to mastectomy, is required, Weiss says. Lumpectomy and radiation are prone to produce the identical results, she says.
“If you are HER2 positive, that doesn’t mean you’ll be better off with a mastectomy,” says Weiss.
“Make your decision about your local treatment options … based on solid data, not on your fear triggered by the aggressive nature of a particular cancer subtype,” Weiss says.