The real false positive rate is much higher than the 5% reported.
The false positive rate reported is ~5% in a sample with an equal number of people that did and did not develop cancer, while the ratio in reality is 1/122 (i.e., 1000 people developed cancer, 122000 did not).
Could still be a useful development, but it does make me wonder about the cost/benefits at this stage.
Unfortunately I can't edit my comment anymore.