The prostate cancer debate has taken yet another interesting turn. Just weeks after the Urological Society of Australia urged all Australian men over 40 to get screened, only to have the Royal Australian College of General Practitioners reconfirm its rejection of screening for men of any age. A major new study just published in the Journal of the American Medical Association (JAMA) has thrown another spanner in the works of screening advocates.
The big problem with screening lots of asymptomatic men for prostate cancer is that many of the cancers that will be found and surgically removed would not have killed the men, had they been left undetected. We know this from the results of a large nine-year European trial published earlier this year where the prostate cancer death rate in men who were screened were compared with the rate in men who were not screened. If early detection was sensible, you would expect that in the screened group, that there would be fewer deaths from prostate cancer because it had been detected early.
The study found that if you screen 1000 men, you will find 82 cases of prostate cancer, and if you follow these men for an average of nine years, there will be 2.94 deaths. In 1000 unscreened men over the same period, 48 cases of prostate cancer will come to light by men presenting symptoms to their doctor. There will be 3.65 deaths. The difference between the two means, in short, that testing saves 0.71 deaths per 1000 men over nine years.
But aside from all these men living with the stress of having being told that they have cancer, the surgical procedure (removal of the prostate) that mostly follows diagnosis causes high levels of urinary incontinence and impotence. According to a review last year by the US Preventive Services Taskforce, one year after surgically removing the prostate gland, 20-70% of men have reduced erectile function, and 15-50% have persisting urinary problems. If prostate cancer would not have harmed many of these men — they would have later died from other causes with prostate cancer, but not from it — then this widespread burden of unnecessary surgical side effects is a major downside of the whole push to have men screened.
Some surgeons have sought to counter this problem by arguing that modern techniques using precision robotic surgery employing the da Vinci robotic surgery machine produce better surgical outcomes. Melbourne’s Professor Tony Costello is one of Australia’s highest profile prostate surgeons. His personal website states that the benefits of robotic surgery “may include reduced risk of incontinence and impotence”. But then again, they may not.
The JAMA study of 1938 men followed for five years reported that, compared to routine “retropubic” radical prostatectomy, minimally invasive prostatectomy performed via robotic surgery “was associated with an increased risk of genitourinary complications (4.7% versus 2.1%) and diagnoses of incontinence (15.9 versus 12.2) and erectile dysfunction (26.8 versus 19.2 per 100 person-years). In other words, the “nerve sparing surgery” being pushed by the handful of surgeons who have invested in it appears to make things worse.
The machines cost $2.7m and in the US, robotic systems cost providers about $US1.2m to run a year. Doctors outlaying such investments plainly have a massive incentive to keep up a healthy through-put of patients using the equipment and one of the ways of doing this is to promote the advantages to patients of better surgical outcomes. Dr Philip Stricker, who set up the robotic surgery program at Sydney’s St Vincent’s Hospital and boasts this week in the on-line medical newsletter 6 Minutes of having performed more robotic prostatectomies than anyone else in NSW, was quick to argue that the American results reflect inexperience “it takes time, experience and technique to achieve equal oncological and potency results” and that “many of the surgeons who adopt this perform few surgeries and therefore never get off their learning curve”.
So what are Australian men to make of such a statement? Can Dr Stricker or anyone else advise Australian men of the independently audited surgical complication rates he and his colleagues around the country achieve using robotic surgery? Can Australian men receive anything beyond reassurances from their doctors, one eye on their hefty investments in the da Vinci equipment, that they will be in good hands?
Simon Chapman is Professor of Public Health at the University of Sydney and NSW Cancer Researcher of the Year 2008