> somewhat reliable marker For the USA... Something around 1.8 million people are diagnosed with cancer per year. At a 50% false negative rate, all else bein

> somewhat reliable marker For the USA... Something around 1.8 million people are diagnosed with cancer per year. At a 50% false negative rate, all else being equal it would detect 900k of those. And all else being equal, at a 0.5% false positive rate, if it were used as suggested it would incorrectly diagnose cancer in around 1.6 million of the population. So around 60% of the people it says has cancer wouldn't have cancer. I guess it depends upon what you mean by "somewhat reliable".