On his Common Sense Family Doctor blog, Dr. Kenny Lin reflects on the 40-year old “War on Cancer” declared by President Richard Nixon, and on the 20-year old Prostate, Lung, Colorectal, and Ovarian Cancer (PLCO) Screening trial. He writes:
“This massive study, which eventually enrolled more than 150,000 men and women between age 55 and 74, was designed to test the widespread belief that screening and early detection of the most common cancers could improve morbidity and mortality in the long term. Not a few influential voices suggested that the many millions of dollars invested in running the trial might be better spent on programs to increase the use of these obviously-effective tests in clinical practice.
They were wrong. As of this week, the PLCO study is 0-for-2.
Miss #1 occurred in March of 2009 when the PLCO study first reported no mortality benefit from annual PSA testing, a test that a majority of men over 50 undergo routinely.
Miss #2 occurred over the weekend, when the Journal of the American Medical Association published a landmark paper that ended with the following paragraph:
We conclude that annual screening for ovarian cancer as performed in the PLCO trial with simultaneous CA-125 and transvaginal ultrasound does not reduce disease-specific mortality in women at average risk for ovarian cancer but does increase invasive medical procedures and associated harms.
One of the ovarian study authors told Reuters:
“Many people will say, ‘Oh it’s just a blood test, oh it’s just an ultrasound, what’s the harm?'” The harm is you might have unnecessary surgery that could hurt you.”
Reuters reports that the ovarian research team “recorded more than 3,000 cases of false-positives in the screening group, and of those, more than 1,000 women who didn’t end up having ovarian cancer had surgery because of a positive test result. Those surgeries resulted in serious complications, including infection or cardiovascular complications, in 163 women.”