Dana Farber. US: A new study from Dana-Farber Cancer Institute found a surprising lack of knowledge among breast cancer
patients about the basic characteristics of their disease – how
advanced it is (stage), whether it is fueled by estrogen, whether it can
be treated with trastuzumab (also called Herceptin,) and the grade
assigned by pathologists.
All these factors are taken into account
when treatments are recommended for women, and the researchers suggest
that patients who fully understand their cancer may be more likely to
adhere to their treatment regimens.
Women from minority groups in
the diverse population of patients studied were less likely than white
women to know this information, according to the findings reported
online by CANCER, a peer-reviewed journal of the American Cancer Society.
“We were really surprised by the results,” said Rachel Freedman, MD, MPH, the first author of the report. Freedman is a medical oncologist in the Susan F. Smith Center for Women’s Cancers at Dana-Farber. Nancy Keating, MD, MPH, of Brigham and Women’s Hospital, is senior author.
The
study is believed to be the first to pose these questions, said
Freedman, who proposed the research after discovering in her own
practice that many women did not understand the reasons for the specific
treatments they were receiving. This “astounding” discrepancy also
emerged in focus group sessions, said Freedman. Although past research
has examined a patient’s general cancer knowledge with regard to basic
treatment rationales and reasons for screening, this is the first study
to examine how much women know about their own cancers.
Telephone
interviews were carried out with 500 women in the California Cancer
Registry who had undergone surgery for breast cancer. They were asked
about the stage of their tumor (0 through 4); whether it was low,
intermediate, or high grade; whether it was ‘HER2-positive’ (generally
treated with trastuzumab), and whether it was ER (estrogen-receptor)
positive. The researchers then compared the answers with the data from
the California Cancer Registry.
The results: 55 percent of women
said they knew their ER status; 33 percent reported knowing their
disease stage; 32 percent said they knew the grade of their tumor, and
13 percent said they knew all four characteristics. Fourteen percent
reported knowing none of them.
In reality, the researchers
determined, 56 percent of women were correct on their ER status, 58
percent reported the correct HER2 status, 57 percent were correct about
the cancer’s stage, and 20 percent reported the correct grade. Only 8
percent were correct on all four questions.
Women who
self-identified as Hispanic or black had less knowledge about their
tumors. Less knowledge was also associated with having less formal
education and lower “health literacy.”
“Of all of these factors, a
tumor’s grade is likely the least important element for patients to
know, although physicians use grade to make decisions about treatments,
including chemotherapy,” Freedman said.
Knowing the stage is more
important, she said, because it is a measure of the patient’s risk, and
the knowing the cancer’s HER2 status could help patients with
HER2-positive tumors understand why they need to take trastuzumab
(Herceptin) for a year. Patients with ER-positive breast cancers often
take tamoxifen or aromatase inhibitors for many years, so that knowledge
might motivate such women to stick to the regimen.
Freedman
believes that patients’ knowledge of their cancer “has to be a good
thing” and plans to look for evidence on that point in further research.
She
also plans to study the effect on patient knowledge of doctors and
health care providers’ different styles in communicating the facts.
She’s considered possible interventions, such as patient videos, smart
phone apps, and checklists.
“Clearly there’s a lot to be done,” Freedman says.
Other
authors are Elena Kouri, PhD, of Harvard Medical School, and Dee West,
PhD, of the Cancer Registry of Greater California. The research was
supported by Komen for the Cure Foundation.