Nearly one-third of early stage breast cancer patients overestimate their risk of cancer recurrence — believing it to be more than double their actual risk. And that overestimation is affecting their quality of life, according to two recent studies.

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The good news? A more nuanced approach to doctor-patient communication may help improve patients' understanding.

Researchers from the University of Michigan Rogel Cancer Center identified two demographically diverse groups of newly diagnosed breast cancer patients in Georgia and Los Angeles County. The project involved mailing surveys to women with favorable-prognosis breast cancer, either ductal carcinoma in situ or early stage invasive breast cancer, about two months after diagnosis. These surveys were done in two phases, which resulted in two samples for analysis.

One sample included 1,295 women and examined the effect of doctor-patient communication on how accurately patients understand their risk of systemic recurrence after treatment. A second sample of 927 women studied how overestimating recurrence affected patients' quality of life and frequency of worry. Both papers were published in Breast Cancer Research and Treatment.

Researchers found that patients who had misperceptions about their risk of recurrence (either over- or underestimating their risk) were more likely to report that their physicians did not discuss risk with them. Those who had a more accurate assessment of their risk of recurrence reported that their physicians discussed risk using both words and numbers.

"Only 9 percent of patients said that their physician talked about risk a lot, and 14 percent reported no conversation about risk at all," explains study author Sarah Hawley, Ph.D., M.P.H., professor of internal medicine at U-M. "Knowing how important it is to patients, we can do better. Physicians and breast cancer clinicians need to pay special attention to talking to patients about risk of recurrence and how possible treatments being offered may influence risk, and then follow up to be sure they understand."

Needing 'a combination of approaches'

Study author Nancy K. Janz, Ph.D., professor of health behavior and health education at the U-M School of Public Health, says, "There are some women who may find discussions about risk more challenging or benefit from a different approach to such discussions.

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"For example, women who are not comfortable with numbers, women who have low health literacy and are less likely to ask questions, or women who are just naturally anxious or worried and may have more difficulty remembering what is said."

Janz says they had hoped to find that patients with low health literacy or difficulty understanding numbers would report more discussions about risk with their physicians.

"Instead, what we found was that women with low numeracy — the ones who may need additional time and explanations — actually reported less discussion," says Janz. "What our research shows us is that physicians need to use a combination of approaches when discussing risk. We recommend using words and numbers, as well as providing written materials so that women can refer to it later."

The researchers also found an association between overestimation and reduced physical and mental health, and especially with the frequency of worry about recurrence. Patients who overestimated both numerically and descriptively had the most worry.

"We asked patients how often their doctor asked about worry, and 60 percent said 'almost never,'" says Hawley. "That's something we think could be improved on. It can be seen as one conversation — make sure they understand using both words and numbers, and address the worry that patients face."

"Everyone with a cancer diagnosis is going to worry, of course," says Hawley. "But if we can help them manage and understand what that actual risk is, using both words and numbers, our results suggest this could lead to less frequent worry and to better quality of life."

Hawley says if surgeons and oncologists assess patients' worry about recurrence, they could identify those patients who may benefit from additional supportive services to manage their worry.

This research was funded by the National Cancer Institute as part of a program project grant (P01 CA163233-03).