"The most common reasons women didn't undergo reconstruction was that they felt it wasn't important, they weren't interested in more surgery or they were focused on their cancer treatment," said lead researcher Dr. Monica Morrow, chief of breast surgery at Memorial Sloan Kettering Cancer Center, in New York City. Also common was fear of the breast implants used for reconstruction, with 36 percent of women citing that as the reason they passed on the surgery.
Whatever their decision, however, nearly 87 percent said they were satisfied four years later, Morrow found.
The study is published online Aug. 20 in the journal JAMA Surgery.
''Part of the reason we did this study is that there has been lots of [discussion] that the rate of breast reconstruction is too low," Morrow said. Some experts believe the options are not explained thoroughly to women, or that women don't understand them.
The goal of the study, Morrow said, was to look at how many women had the reconstruction, why some decided against it, and whether they were satisfied with their decision.
After reviewing government data, the 485 women who were included in the study's final analysis had been diagnosed with breast cancer between 2005 and 2007 and were disease-free four years later.
Black women and those with less education were less likely to choose breast reconstruction, Morrow found. The older the woman, the more likely she was not to choose reconstruction. And women who had another major health problem and those who had chemotherapy were also less likely to choose reconstruction.
About 16 percent of the women said they could not take time off from work to undergo more surgery.
Lack of insurance was cited by nearly 12 percent of the women. Under the 1998 federal law known as the Women's Health and Cancer Rights Act, most group insurance plans that cover mastectomies must also cover breast reconstruction. However, doctors note that sometimes the reimbursement rates are low, particularly with Medicare and Medicaid patients, so some surgeons won't accept the rates.
About 18 percent of the women in the study said they did not know reconstruction was an option.
"We did find, however, that there was a higher likelihood that nonwhite women and women with lower education were more likely to express some level of dissatisfaction with the decision-making process if they didn't do it," Morrow added.
The findings point to the need for health-care providers to address patients' misconceptions, Morrow and her co-authors wrote.
"I think most of this is good news," she said. "It says most women who want reconstruction are getting it and that those who don't get it have chosen not to, basically.
"There is no 'right' number of women who should be getting reconstruction," Morrow added. She understands why some women choose not to have the surgery. "When you are faced with a life-threatening illness, reconstruction may not be the first thing on your mind," she said.
The study is mostly good news, agreed Dr. Nora Hansen, chief of the division of breast surgery at the Northwestern University Feinberg School of Medicine. "For the most part, patients are satisfied with the treatment they have gotten," she said.
In her own practice, which includes many women with higher incomes and education, Hansen said closer to 70 percent of women opt for reconstruction after mastectomy.
The 42 percent reconstruction rate found by Morrow is actually encouraging, said Dr. Laura Kruper, director of the Cooper-Finkel Women's Health Center and an assistant professor of surgical oncology at the City of Hope Cancer Center, in Duarte, Calif.
"Past studies have documented that average reconstruction rates after mastectomy range from 25 to 35 percent," she said. "The reality is that there will always be some women who do not wish to have breast reconstruction after mastectomy."
Even so, Kruper said, more patient education is needed. She cited the 24 percent of women in the study who said they did not have reconstruction because of concerns about interference with detection of breast cancer recurrence with implants -- a concern experts say is not warranted.
To learn more about insurance for breast reconstruction, visit the U.S. National Cancer Institute.