SAN DIEGO -- Estimating survival in prostate cancer proved to be a formidable task for a group of unselected adults, whether left to their own information-gathering devices or using a prostate cancer nomogram.
By searching the Internet on their own, fewer than 20% of 140 study participants came within 10 percentage points of a hypothetical patient's likely 15-year cancer-specific survival. The proportion of "ballpark" estimates increased to 50% with the aid of a prostate cancer nomogram -- even though only a fourth of the study participants could figure out how to use the nomogram.
Given that study participants had above-average education, the results probably underestimated most adults' ability to project survival in newly diagnosed prostate cancer, as reported here at the American Urological Association meeting.
"These findings suggest that even in a population more educated than the average U.S. citizen, unrestricted Internet searching often leads to poor estimates of survival," said Lucas P. Labine, a medical stuent at the University of Minnesota in Minneapolis. "Clinicians should consider guiding patients to appropriate online health resources so that patients can obtain more accurate information and make informed decisions."
Physicians, including urologists, might not fare much better in a similar test, even if they used a nomogram, suggested Mitchell Benson, MD, of Columbia University in New York City.
"I'm not sure how the urologic community does with nomogram use," said Benson, co-moderator of Labine's presentation. "There are so many that at times you might get confused."
An unidentified member of the audience took the conversation a step further, suggesting that a patient whose survival estimate came from one of the more "optimistic" nomograms would go away feeling pretty good, whereas an estimate from a less optimistic nomogram would "leave the guys quite disappointed."
Co-moderator James Mohler, MD, of Roswell Park Cancer Institute in Buffalo, N.Y., added that nomograms are "far too complex to allow the average patient to plug in the data and getting meaningful information."
Communicating risk has always been an essential component of cancer care and clinical decision-making. Historically, patients have relied almost exclusively on physicians for information about risk and other aspects of their care. Today, however, most adults use the Internet as their primary source of information about and medicine and healthcare, Labine said.
Several validated nomograms have been developed to help inform risk estimates for cancer and a variety of other diseases. Studies have shown that the statistical models often outperform expert clinicians in estimating a patient's risk, Labine said. Whether nomograms are sufficiently "user friendly" for the general population has remained unclear.
To examine unselected adults' ability to use a nomogram developed for prostate cancer, Labine and colleagues recruited study participants attending the Minnesota State Fair. Each participant was given a pathology report for a hypothetical 69-year-old man who had undergone radical prostatectomy. The key pathology findings were a Gleason score 4+5 and pathological stage T3aN1M0 (high-grade, locally advanced disease).
Participants were asked to estimate the patient's 15-year cancer-specific survival, using the Internet to search for information on their own. Each participant repeated the task using a validated nomogram available online.
With correct use of the nomogram, the patient had an 88% likelihood of not dying of prostate cancer within 15 years. For purposes of the study, investigators defined a "ballpark" estimate as being within 10 percentage points of the true estimate.
Of the 140 participants recruited, 129 completed the study. Women accounted for two-thirds of the group, which had a median age of 47, was predominately white (81%), and was well educated (77% college degree).
By performing unaided Internet searches, the study participants came up with an average estimated 15-year survival of 40% for the hypothetical patient. By use of the nomogram, the average estimated 15-year survival increased to 82%.
Examination of study participants' individual performance showed that 25 of 129 (19%) arrived at a ballpark estimate of 15-year survival by searching the Internet on their own. The 25 ballpark estimates averaged 87.68% compared with 34.46% for the remaining 104 participants.
When using the nomogram, 66 (51%) of the participants arrived at ballpark estimates averaging 89.74%, whereas the remaining 63 participants came up with 15-year survival estimates that averaged 39.56%.
An analysis of factors associated with ballpark estimates identified education as the only significant predictor, as participants with a college degree were more than twice as likely to obtain a ballpark estimate by use of the nomogram (OR 2.6, 95% CI 1.1-6.1, P=0.03).
"Most participants underestimated prognosis given the hypothetical pathology report when using unrestricted internet searching," Labine said. "Physicians have an opportunity to help guide patients with accurate information about their cancer prognosis online, and this may lead to improved shared decision making."
Labine and co-authors disclosed no relevant relationships with industry.