Angelina Jolie is leading more women to get tested for genes that can cause breast cancer, according to new research. And not just any women, but women who are actually in danger.

But if that leads them to get double mastectomies, as Jolie did, the benefits may be limited at best. Another study released this week suggests that removing both breasts does not improve survival chances compared with surgery that just removes a tumor followed by radiation.

The research about the “Jolie effect” was presented at the American Society of Clinical Oncology Breast Cancer Symposium in San Francisco this week, Canadian researchers claimed to demonstrate the medical benefits of “the Angelina effect,” CityNews Toronto reported.

“The Angelina effect seemed to increase the awareness and the referral for women who were truly at high risk for hereditary breast cancer,” said Andrea Eisen, head of the Familial Cancer Program at Sunnybrook Health Science Centre in Toronto. “It’s not just worried women who came in, or those who have moderate or low risk — it was really high risk women who perhaps were concerned before about pursuing genetic counselling or genetic testing.”

Meanwhile, a study of 200,000 patients with cancer of just one breast published in the Journal of the American Medical Association (JAMA) found some double mastectomies unwarranted. Survival rates for patients who had lumpectomies to treat cancer were nearly identical to those who had both breasts removed: 82 percent.

“There’s no guarantee that by having the second breast removed that you will do better,” said Len Lichtenfeld, deputy chief medical officer of the American Cancer Society, who had no role in the research.

Jolie leaped into the breast cancer debate with “My Medical Choice,” a New York Times opinion piece published on May 13, 2013. She said she was a carrier of BRCA1, a gene that increased her chances of getting breast and ovarian cancer. Her doctor said she had an 87 percent chance of developing breast cancer, she wrote, and her own mother died of the disease at 56. To head off this risk, Jolie had a double mastectomy.

I am writing about it now because I hope that other women can benefit from my experience,” Jolie wrote. “Cancer is still a word that strikes fear into people’s hearts, producing a deep sense of powerlessness. But today it is possible to find out through a blood test whether you are highly susceptible to breast and ovarian cancer, and then take action.”

According to Eisen’s team, women did.

Sunnybrook looked at data from six months before and six months after Jolie’s op-ed. Among the findings:

  • 487 women were referred for genetic counseling before the op-ed compared with 916 after — an increase of 105 percent
  • 437 women in the group referred after the op-ed were considered “high risk” — an increase of 90 percent
  • 61 women were found to have a potentially harmful BRCA mutation after the op-ed compared with 29 before — an increase of 32 women, or 110 percent

“Among the larger number of women we saw for genetic counselling after the news, the proportion of women determined to be high risk, like Ms. Jolie, was about the same as the proportion seen before the news, suggesting that we continue to see many of the women who need screening most,” Eisen said in a statement.

The study did not offer evidence that the women had heard about Jolie’s situation. But other cancer specialists have previously credited Jolie with having a significant impact on awareness as well as action by women.

“It was very powerful in the public health setting,”  Mercy Laurino, a genetic counselor in the Cancer Prevention Clinic at Seattle Cancer Care Alliance, reported in May. “It allowed genetic testing to be an OK conversation. Patients would come to us and say my mom died of breast or ovarian cancer. And then they’d say, ‘You know, like Angelina Jolie.’ It created a starting point to discuss genetic testing and discuss other cancer genes, as well. They may bring up BRCA1 and 2 but they may not know all the other cancer genes out there. But since they get the concept, it made it easier to explain genetics education with them and the concept of inheritance.”

The Angelia effect, it seems, is global.

“I’ve traveled to the Philippines and China and Vietnam and it’s all over,” Laurino said. “I saw vendors promoting cancer genetic testing at an oncology meeting in China and they had big pictures of Angelina Jolie in their booths. Before, I would introduce the concept of genetic testing and counseling and the importance of family history but now, they’re generating it. People get it.”

A similar study of the “Katie Couric effect” showed that Couric’s March 2000 colon cancer awareness campaign was associated with at least a temporary increase in the number of people getting colonoscopies.

Though she’s moved on to speaking out against sexual violence and marrying Brad Pitt since her opinion piece, Jolie may delight in this news. Even before the new JAMA study, coverage of the Angelina effect and BRCA testing has not always been positive.

Six months after “My Medical Choice,” the U.S. Preventive Services Task Force, a volunteer health service that reports to Congress, warned of unnecessary BRCA testing — a warning that ABC News wrote about under the headline “Why the Angelina Effect is at Odds with New Guidelines.”

“”The USPSTF recommends against routine genetic counseling or BRCA testing for women whose family history is not associated with an increased risk for mutations in the BRCA1 or BRCA2 genes,” it said.

“There is a very clear-cut algorithm for whether or not to test someone for a BRCA mutation,” said Jennifer Ashton, a practicing obstetrician and ABC News contributor who reviewed the study. “Simply having breast cancer in the family is not sufficient.”

In December, NPR reported that “researchers at the University of Maryland and Johns Hopkins surveyed over 2,500 Americans and found that while 3 out of 4 knew that Jolie had gotten a mastectomy, fewer than 10 percent properly understood Jolie’s condition. … Indeed, Jolie might have gotten some people more confused about how a family history of cancer plays into an individual’s risk, the survey found.”

As researchers debate the need for BRCA testing, Jolie remains an inspiration to those deciding what to do about the illness.

“I was thrilled when she did that,” Bonnie Stanfield, who had a preventative mastectomy after her daughter died of breast cancer, told CityNews about “My Medical Choice.” “A lot of women don’t really know what this gene mutation is about, don’t know how to go about finding out.”