(Reuters Health) - The likelihood that U.S. women with early-stage cancer in one breast will have both breasts removed varies depending on where they live, a new study shows. 
 
 For example, between 2010 and 2012, among women ages 20 to 44 with cancer in one breast, about 15 percent had both breasts removed in the District of Columbia, compared to about 49 percent in South Dakota. 
 
 “The variation is very striking,” said senior author Ahmedin Jemal, of the American Cancer Society in Atlanta. 
 
 When women have breast cancer in one breast, having both breasts removed usually isn’t helpful, experts say. Last year the American Society of Breast Surgeons issued a statement to discourage women with one-sided, or unilateral, breast cancer who don’t have a genetic or family risk for the disease from undergoing a double, or contralateral, mastectomy. 
 
 Still, Jemal and his colleagues point out in JAMA Surgery, past research has found an increase in contralateral mastectomies among women with early stage cancer in one breast. 
 
 For women at average risk and cancer in one breast, “taking off the other breast doesn’t significantly reduce the risk of a cancer on the other side, because their risk wasn’t that high to begin with,” said Dr. Laurie Kirstein, a breast surgical oncologist at Memorial Sloan Kettering Cancer Center in New York City who wasn’t involved in the new study. 
 
 To examine trends across states, the researchers analyzed data collected between 2004 and 2012 from more than 1.2 million women with early stage cancer in one breast. 
 
 Across the country, the proportion of such women ages 20 to 44 who opted for contralateral mastectomy rose from about 11 percent to about 33 percent. Over the same period, the proportion of similar women age 45 and older who had both breasts removed rose from about 4 percent to about 10 percent. 
 
 Rates of contralateral mastectomy varied by state but were consistently highest in women ages 20 to 44. 
 
 During the last two years of the study, more than 40 percent of women in that age range who lived in South Dakota, Iowa, Colorado, Missouri, Nebraska, Tennessee, Maine and Montana chose to have both breasts removed. That was true for less than 25 percent of such women who lived in New Hampshire, Delaware, New Jersey, Louisiana, Idaho, Alaska, South Carolina, Nevada, Massachusetts, Wyoming, Hawaii and the District of Columbia. 
 
 The researchers also looked at the proportion of women undergoing reconstructive surgery after having both breasts removed. They found that while the highest rates of double breast removals were generally clustered in the Midwest, the highest rates of breast reconstruction afterward were generally clustered in the Northeast. 
 
 Jemal told Reuters Health that the study can’t explain why so many women are opting for contralateral mastectomies, but the rate in the U.S. is higher than in other countries. 
 
 For example, only 2 percent to 3 percent of women in the UK with cancer in one breast have the other breast removed, too, compared to 13.5 percent in the U.S. 
 
 The researchers didn’t have information on how many of the women in the study were at higher risk for breast cancer because it runs in their family or because they had been treated in the past with radiation therapy to the chest. 
 
 Kirstein told Reuters Health that for women with a genetic predisposition to breast cancer, “the bilateral mastectomy is seen as a risk reducing procedure.” 
 
 She said some women who aren’t at higher risk still choose to have the cancer-free breast removed even after learning about the risks and benefits. 
 
 The variation in rates by state may be explained by healthcare access, income and what women suggest to each other about treatments, she told Reuters Health. 
 
 Doctors need to have detailed conversations with women about their treatment options, said Jemal. 
 
 “First, the surgeons have to have this discussion with the patient,” he said. “Second, patients have to take time to make a decision. They don’t want to make the decision right away, because anxiety is very high right after diagnosis.” 
 
 Kirstein said she asks patients to think of how they’ll feel about their decision in 10 years. 
 
 “We support whatever the patients want to do, but we want them to understand what they’re doing,” she said. 
 
 SOURCE: bit.ly/2nE8hg7 and bit.ly/2nE7cEV JAMA Surgery, online March 29, 2017. 

 (CNN) For many, the Fourth of July evokes jovial memories of backyard cookouts and fireworks, but for Amberlea Childs, the summer holiday conjures a haunting memory that changed her life. 
 
 Childs was diagnosed with breast cancer a day before July Fourth weekend in 2010. 
 
 She was 36, newly engaged, and had a lump the size of a large walnut in her right breast. She visited a radiologist to get it checked. 
 
 "He ended up doing five different biopsies, and on the last one, he pulled it out, and he looked at me, and his eyes welled up with water," Childs said. 
 
 "It was definitely that out-of-body experience where you're kind of watching your own story play out, and as his eyes welled up, he said, 'I'm not 100% sure, but if I had to bet, I'm 99.9% sure what I just pulled out of your breast was breast cancer,' " Childs said. 
 
 Later on, once her diagnosis was confirmed, "I needed to have surgery." 
 
 Amberlea Childs, third from the left, in treatment in St. Petersburg, Florida. 
 
 Childs first opted to have a lumpectomy, in which only the cancerous mass in her breast was removed, but then the disease advanced. She was told that she would need another surgery. This time, she opted for a double mastectomy, in which both of her breasts -- even the one without cancer -- were removed. 
 
 "I wanted to do a mastectomy on that right side, and then from there, you have to then contemplate, 'Well, should I do a prophylactic mastectomy on the other side that does not have cancer?' " Childs said. "Many women have this thought, but I feel for a younger woman -- and I identify as a young survivor -- you have longer to live, therefore you have a greater chance of recurrence just by the mere fact that you're going to be alive longer." 
 
 Since her cancer diagnosis, Childs has had nine surgeries to her chest. The double mastectomy was among the earliest. 
 
 Amberlea Childs, with her husband Donny, last year. 
 
 Now, she is a healthy 43-year-old Milwaukee resident and a breast health advocate with Susan G. Komen of Southeast Wisconsin . While chemotherapy treatments affected Childs' fertility, she and her husband are preparing to adopt their first child, whom they can't wait to meet. 
 
 "I am feeling wonderful. I can honestly say that my life is healthier, better directed after I've had cancer," she said. "It gave me a different lens to look through life." 
 
 Yet because of her experience, Childs can relate to the 7% of women with breast cancer who are diagnosed before age 40, many of whom face the same decision she did: whether to go under the knife for a lumpectomy or a mastectomy. 
 
 'The cancer didn't develop overnight, so pump the brakes' 
 
 Younger women with breast cancer are increasingly opting to undergo double mastectomies, even if they were diagnosed with early-stage cancer in only one breast, known as unilateral breast cancer, according to a study published in the journal JAMA Surgery on Wednesday. 
 
 The procedure to remove the healthy breast along with the affected breast is called a contralateral prophylactic mastectomy , or CPM. 
 
 In certain states, more than 42% of women 20 to 44 who underwent surgery between 2010 and 2012 opted to remove both breasts with a CPM, the study found. Researchers now are hoping to determine why. 
 
 "To be honest, I think it's very difficult to really pinpoint why the increase," said Ahmedin Jemal, vice president of surveillance and health services research at the American Cancer Society, who was senior author of the study. However, he offered some ideas. 
 
 "One factor that could contribute to the increase is this desire for symmetry," Jemal said, referencing how the breasts would look more symmetrical after a double mastectomy compared with after having just one breast removed. 
 
 "Another factor is probably the Angelina Jolie effect . She was diagnosed with the BRCA-1 cancer gene that mutation that causes breast cancer, and she had a double mastectomy, so that was covered widely in the media," he said. "For women diagnosed with breast cancer in one breast, there is no evidence to suggest to remove the unaffected breast." 
 
 Last year, the American Society of Breast Surgeons published a consensus statement in the journal Annals of Surgical Oncology recommending against the routine use of removing both breasts in women with unilateral breast cancer -- a recommendation that the American Board of Internal Medicine also made. 
 
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 "CPM should be discouraged for an average-risk woman with unilateral breast cancer. However, patient's values, goals, and preferences should be included to optimize shared decision making when discussing CPM. The final decision whether or not to proceed with CPM is a result of the balance between benefits and risks of CPM and patient preference," the statement said. 
 
 On the other hand, the most common second cancer in breast cancer survivors is another breast cancer, according to the American Cancer Society 
 
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 A healthy 55-year-old woman has about a 2.5% chance of developing invasive cancer in a given breast over the next 15 years, whereas a 55-year-old breast cancer survivor has a 10% to 15% chance, according to a paper published in the Journal of the National Cancer Institute in 2010. 
 
 About 12.4% of women in the United States will be diagnosed with breast cancer at some point during their lifetime, according to the National Cancer Institute 
 
 "Sometimes, surgery is a blessing, and it can help remove cancer and do great things, but it doesn't come cost-free, and it doesn't come complication-free," Childs, the breast cancer survivor, said. 
 
 "There is going to be time that's needed to heal and recover, and if you're not willing to give yourself that time, maybe you should weigh that into your decision if it was lumpectomy versus mastectomy, but I think, do the homework. Don't rush into something so quickly. Take the time, get that extra opinion, meet with one more plastic surgeon," she said. 
 
 "This is the best piece of advice I've been told and I always share with other women: The cancer didn't develop overnight, so pump the brakes and take more time to make the best informed decision for you." 
 
 Differences in mastectomies, by age 
 
 The new study included data on 1.2 million women 20 and older in the United States who were diagnosed with early-stage invasive unilateral breast cancer between 2004 and 2012. The data came from the North American Association of Central Cancer Registries 
 
 The researchers took a close look at which patients in the data underwent a lumpectomy; a unilateral mastectomy, in which only the breast with cancer is removed; or a contralateral prophylactic mastectomy. 
 
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 A limitation, however, was that the researchers were unable to determine which patients may have been at a higher risk for a second cancer due to family history or genetic risk, as well as their socioeconomic status. Those factors are individually associated with the likeliness of receiving a CPM. 
 
 "Genetic testing is more commonly performed in younger women with breast cancer, and genetic predispositions are more common," said Dr. Michael Sabel, a professor of surgical oncology and the chief of the division of surgical oncology at the University of Michigan, who was not involved in the new study. 
 
 "Many of these women may have had CPM because they harbor a genetic mutation, but I don't think the authors had that data," he said. 
 
 Among all the women in the study, 58.4% had a lumpectomy, 32.9% had only the breast with cancer removed, and 8.7% had both breasts removed. 
 
 The researchers found that the proportion of women opting for CPM declined with age. Only 2.4% of those 70 or older had both breasts removed, compared with 29.3% of those 20 to 29. 
 
 Nationally, the prevalence of CPMs also increased over time. Between 2004 and 2012, the number of women 45 and older who had both breasts removed jumped from 3.6% to 10.4%. For women 20 to 44, the number rose from 10.5% to 33.3%. 
 
 "It is not surprising that younger women opt for CPM compared to older. The issue is what contributes to such a decision. This trend is multifactorial," said Dr. Francisco Esteva, a medical oncologist at NYU Perlmutter Cancer Center, who was not involved in the new study. 
 
 "For young women, they realize that they are at risk life long for a second cancer in the contralateral breast, and there is good data that the perception of this risk is greater than the real risk, but many women, with this knowledge, decide to make a definitive intervention," he said. 
 
 By the time many women come to their surgery, they may have undergone multiple studies and interventions, which can be overwhelming, Esteva said. 
 
 "To consider ongoing higher-risk surveillance with mammograms, sonograms, possible breast MRIs, probable multiple biopsies, many benign, just becomes unacceptable and too stressful," he said. "The women choosing bilateral mastectomy are choosing freedom from that." 
 
 Sabel offered another idea. "MRI is more commonly performed in younger women with denser breast tissue, and we know that MRI, being more sensitive, can lead to additional findings that lead women to opt for bilateral mastectomy," he said, but more research is needed. 
 
 "Most of the literature shows a similar pattern, with CPM being strongly associated with decreasing age," he said. "However, this still seems particularly high in those Midwestern states, and genetics or MRI wouldn't explain all of it." 
 
 Indeed, the study also revealed regional differences in the rate of CPMs. 
 
 Where women are more likely to get healthy breasts removed 
 
 "What we didn't expect was that we found the highest proportion in the Midwestern states, Nebraska, Missouri, Iowa, Colorado and South Dakota," Jemal said. 
 
 Those are the states in which more than 42% of women 20 to 44 who underwent surgery between 2010 and 2012 opted to remove both breasts with a CPM. 
 
 The study findings also showed significant increases in the percentage of women 20 to 44 who opted to receive CPMs between 2004 and 2006 compared with between 2010 and 2012, said Dr. Deborah Axelrod, a breast surgeon at the NYU Perlmutter Cancer Center in New York. She was not involved in the new study. 
 
 "The numbers are staggering," Axelrod said. 
 
 "In New York, for instance, which is where I practice, 11% of women in the early years had contralateral prophylactic mastectomy, which then rose to 28% in the later years," she said. "It's really shocking to see that dramatic of an increase." 
 
 The trend appeared to continue across the East Coast. Axelrod pointed to Virginia, where 9.8% of younger women underwent CPMs between 2004 and 2006 and 32.2% between 2010 and 2012. In Rhode Island, 7.6% rose to 25.8%, and in West Virginia, 6% rose to 26.4%. 
 
 In Wisconsin, where Childs, the breast cancer survivor, lives, 13.8% rose to 32.7%. 
 
 Axelrod added that she didn't think the increase could be explained on the basis of advances in developing better reconstructive techniques for mastectomies, since the rates of breast reconstruction advances did not seem to parallel the increase in mastectomies. 
 
 "The study confirms several previous studies from single institutions and from large databases showing the increase in the use of contralateral prophylactic mastectomies," said the University of Michigan's Sabel. 
 
 "The variability by states is very interesting and raises many questions," he said. 
 
 Double mastectomies tripled in 10 years 
 
 Sabel and his colleagues found in a separate study that the percentage of women who were eligible for lumpectomies but opted for double mastectomies rose between 2000 and 2012. The study was published in The Breast Journal last year. 
 
 "Further examination on how to optimally counsel women about surgical options is warranted," the authors of that study wrote. 
 
 Join the conversation See the latest news and share your comments with CNN Health on Facebook and Twitter. 
 
 Overall, Axelrod, the breast surgeon in New York, said that physicians should make more of an effort to have a balanced discussion with patients and try to dissuade them from removing a healthy breast without significant risk factors such as a BRCA gene mutation. 
 
 "There is a responsibility on the part of physicians to explain to women what their options are and why it's not recommended to have the healthy breast removed, assuming that they're in the general pool of women with breast cancer and they don't have a mutation, and they don't have any other mitigating factors that we look at to say 'you are at an increased risk,' " Axelrod said. 

 Key Points 
 
 Question Does the proportion of contralateral prophylactic mastectomies vary by state? 
 
 Findings In this cohort study of more than 1.2 million women who received a diagnosis of invasive unilateral early-stage breast cancer treated with surgery, the proportion of contralateral prophylactic mastectomies varied substantially by state. The proportion among women 20 to 44 years of age during the period from 2010 to 2012 ranged from 15.7% in Hawaii to 42.8% to 48.5% in 5 contiguous Midwestern states. 
 
 Meaning Patients should be educated about the benefit and harm of a contralateral prophylactic mastectomy for informed decision making. 
 
 Abstract 
 
 Importance The use of contralateral prophylactic mastectomies (CPMs) among patients with invasive unilateral breast cancer has increased substantially during the past decade in the United States despite the lack of evidence for survival benefit. However, whether this trend varies by state or whether it is correlated with changes in proportions of reconstructive surgery among these patients is unclear. 
 
 Objective To determine state variation in the temporal trend and in the proportion of CPMs among women with early-stage unilateral breast cancer treated with surgery. 
 
 Design, Setting, and Participants A retrospective cohort study of 1.2 million women 20 years of age or older diagnosed with invasive unilateral early-stage breast cancer and treated with surgery from January 1, 2004, through December 31, 2012, in 45 states and the District of Columbia as compiled by the North American Association of Central Cancer Registries. Data analysis was performed from August 1, 2015, to August 31, 2016. 
 
 Exposure Contralateral prophylactic mastectomy. 
 
 Main Outcomes and Measures Temporal changes in the proportion of CPMs among women with early-stage unilateral breast cancer treated with surgery by age and state, overall and in relation to changes in the proportions of those who underwent reconstructive surgery. 
 
 Results Among the 1 224 947 women with early-stage breast cancer treated with surgery, the proportion who underwent a CPM nationally increased between 2004 and 2012 from 3.6% (4013 of 113 001) to 10.4% (12 890 of 124 231) for those 45 years or older and from 10.5% (1879 of 17 862) to 33.3% (5237 of 15 745) for those aged 20 to 44 years. The increase was evident in all states, although the magnitude of the increase varied substantially across states. For example, among women 20 to 44 years of age, the proportion who underwent a CPM from 2004-2006 to 2010-2012 increased from 14.9% (317 of 2121) to 24.8% (436 of 1755) (prevalence ratio [PR], 1.66; 95% CI, 1.46-1.89) in New Jersey compared with an increase from 9.8% (162 of 1657) to 32.2% (495 of 1538) (PR, 3.29; 95% CI, 2.80-3.88) in Virginia. In this age group, CPM proportions for the period from 2010 to 2012 were over 42% in the contiguous states of Nebraska, Missouri, Colorado, Iowa, and South Dakota. From 2004 to 2012, the proportion of reconstructive surgical procedures among women aged 20 to 44 years who were diagnosed with early-stage breast cancer and received a CPM increased in many states; however, it did not correlate with the proportion of women who received a CPM. 
 
 Conclusions and Relevance The increase in the proportion of CPMs among women with early-stage unilateral breast cancer treated with surgery varied substantially across states. Notably, in 5 contiguous Midwest states, nearly half of young women with invasive early-stage breast cancer underwent a CPM from 2010 to 2012. Future studies should examine the reasons for the geographic variation and increasing trend in the use of CPMs. 

 There was a large geographic variation in rates of double mastectomies across the country, which suggests that doctors aren’t properly explaining the risks and the lack of survival benefit to patients, Dr. Hwang said. “There are important regional differences in how communication occurs between patient and surgeons,” she said, noting “it is clearly not plausible that there are biologically based regional differences.” 
 
 The new study looked back at 1.2 million women age 20 and older from 45 states and the District of Columbia who had been given an early stage breast cancer diagnosis in one breast between Jan. 1, 2004, and the end of 2012. (The only states not included, for various reasons, were Maryland, Illinois, Vermont, Kansas and Minnesota.) Most of the cancers were in women over 45. The data was compiled by the North American Association of Central Cancer Registries, and the investigators were from the American Cancer Society, Emory University, Dana-Farber Cancer Institute and Brigham and Women’s Hospital. 
 
 Among women of all ages who had been given a diagnosis of breast cancer during this period, most — 58.4 percent – had lumpectomies to remove tumors from the affected breast, but left the healthy breast alone. Another 32.9 percent had a single mastectomy, and 8.7 percent had both breasts removed, the study found. But the percentage of women of all ages who chose to have both breasts removed increased to 13 percent of all those who had surgery in 2012, up from 4.5 percent in 2004. 
 
 The rate of double mastectomies was highest among women under 45. But the rate increased among women 45 and older as well. The percentage of older women having double mastectomies rose to 10.4 percent in 2012, up from 3.6 percent in 2004. 
 
 The lowest rates of double mastectomies for younger women over all were in Hawaii, where 15.7 percent of all women with cancer in one breast had both breasts removed, and the District of Columbia, with a rate of 14.6 percent.
– In 2004, one in 10 American women under the age of 45 with cancer in one breast opted to have the second, healthy breast removed as well. Just eight years later, it had increased to one in three women, according to a study published Wednesday in JAMA Surgery. When looking at breast cancer patients of all ages in 2012, only 13% opted to have the healthy breast removed with the cancerous one; but that's still a major increase from 4.5% in 2004. The New York Times reports there's no evidence that removing a healthy breast will reduce a person's chances of dying from breast cancer in the future. In fact, the American Board of Internal Medicine and the American Society of Breast Surgeons recommend against it. So, it's unclear why breast cancer patients are increasingly choosing to go that route. Ahmedin Jemal, senior author of the study, tells CNN it may be for symmetry or because of the widespread coverage of Angelina Jolie's choice to have both breasts removed. Or maybe patients just don't believe doctors when they say removing a healthy breast doesn't significantly reduce their risk of developing breast cancer a second time. Jemal also says there was a "very striking"—and unexplained—geographical difference in the number of women choosing to have a healthy breast removed, Reuters reports. The highest rates were seen in five contiguous states in the Midwest; the lowest in Hawaii. (Meanwhile, a report found the number of women diagnosed with breast cancer could double by 2030.)