A Small Study Offers Insight On Breast Cancer Patients’ Capacity and Eagerness to Participate in Medical Decisions

Last week the journal Cancer published a small but noteworthy report on women’s experiences with a relatively new breast cancer decision tool called Oncotype DX. This lab-based technology, which has not received FDA approval, takes a piece of a woman’s tumor and, by measuring expression of 21 genes within, estimates the likelihood, or risk, that her tumor will recur.

As things stand, women who receive a breast cancer diagnosis face difficult decisions regarding the extent of surgery they should undergo (see the New York Times‘ article of last week, with over 200 people weighing in on this ultra-sensitive matter). Once the surgeon has removed the tumor, choices about chemotherapy, hormone modifiers, radiation and other possible treatments challenge even the most informed patients among us.

Oncotype DX and similar techniques, like the FDA-approved Mammaprint, provide a more detailed molecular profile of a malignancy than what’s provided by conventional pathology labs. For women who have early-stage (non-metastatic), estrogen-receptor positive (ER+) breast cancer, this test provides risk-assessment that’s personalized, based on gene expression in the individual’s tumor.

Oncotype DX has been commercially available since 2004. The test “reads” three levels of risk for breast cancer recurrence at 10 years: “low” if the predicted recurrence rate is 11% or less, “intermediate” if the estimated rate falls between 12% and 21%, and high if the risk for recurrence is greater than 21%.

The investigators, based at the University of North Carolina, Chapel Hill, identified women eligible for the study who had an ER+, Stage I or II breast cancer removed and tested with the Oncotype Dx tool between 2004 and 2009. The researchers sent surveys to 104 women, of whom 78 completed the questionnaires and 77 could be evaluated for the study. They distributed the surveys between December, 2008 and May, 2009.

Several factors limit the study results including the small number of participants and  that the women were treated at just one medical center (where the oncologists were, presumably, familiar with Oncotype Dx). The patients were predominantly Caucasian, the majority had a college degree and most were financially secure (over 60% had a household income of greater than $60,000). Nonetheless, the report is interesting and, if confirmed by additional and larger studies involving other complex test results  in cancer treatment decisions, has potentially broad implications for communication between cancer patients and their oncologists.

Some highlights of the findings:

1. The overwhelming majority of women (97% of the survey respondents) recalled receiving information about the Oncotype Dx test from their oncologists. Two-thirds (67%) of those women reported they “understood a large amount or all” of what the doctors told them about their recurrence risk based on the test results.

2. Nearly all of the respondents (96%) said they would undergo the test if they had to decide again, and 95% would recommend the test to other women in the same situation.

3. Over three-quarters, 76% “found the test useful” because it determined whether there was a high chance their cancer would come back.

4. The majority of respondents (71%) accurately recalled their recurrence risk, indicating a number within 4% of that indicated by their personal test results.

Taken together, these findings support that a majority of women with breast cancer whose oncologists shared with them these genomic testing results, and who filled out the surveys, had good or excellent recall of the Oncotype Dx reports and felt that the test was helpful.

As an aside, the women were asked to rate their preferences regarding their personal input in medical decisions. Among the 77 respondents, 38% indicated they prefer to have an active role in medical decisions (meaning that they prefer to make their own decisions regardless of the doctor’s opinion or after “seriously considering” the doctor’s opinion) and 49% indicated they like a shared role, together with their doctors, in medical decisions. Only 13% of the women said they “prefer to leave the decision to <the> doctor.”

What’s striking is that among these women with early-stage breast cancer, 85% said they like to be involved in medical decisions. And 96% said they’d undergo the test again. Most of the women, despite imperfect if not frankly limited numeracy and literacy (as detailed in the publication) felt they understood the gist of what their doctors had told them, and indeed correctly answered questions about the likelihood of their tumor’s recurrence.

The results are encouraging, overall, about women’s eagerness to participate in medical decisions, and their capacity to benefit from information derived from complex, molecular tests.

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*The capacity of Oncotype Dx to accurately assess the risk of breast cancer recurrence has been evaluated in previous, published studies including a 2004 publication in The New England Journal of Medicine and a 2006 paper in the Journal of Clinical Oncology. The test is manufactured, run and marketed by Genomic Health, based in Redwood City, California.

The National Cancer Institute lists an ongoing trial for women with hormone receptor-positive, node-positive breast cancer that includes evaluation with the Oncotype Dx tool.

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• Mind over Matter? Don’t Kid Yourself (on Stress and BC)
• Why Blog on OncotypeDx and BC Pathology?
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