According to the NY Times, the USPTF has issued another dictum, namely that testing for ovarian cancer has no merit. They states:
Tests commonly recommended to screen healthy women for ovarian cancer do more harm than good and should not be performed, a panel of medical experts said on Monday.
Now this may not be exactly true, but it is mostly. There are two simple tests for ovarian cancer, CA125 in the blood and ultrasound exams of the ovaries. They are not bad, but, and here is the real problem, they do not seem to make themselves evident until too late a time. Why? Ovarian cancer grows very rapidly. Thus if one has a yearly interval, and the cells double at say a 5 day rate or even less, then at say 3.65 doubling there is 2^100 times the cell, roughly. That means a massive tumor in a ear.
Thus the question is how frequently should one scree to see a material change in survival in ovarian cancer from such screening. Again no one seems to have even thought of the correct question. But alas the USPTF seems to have this chronic ailment.
If one asks the question then I suspect based upon a back of the envelope test one should test every month or so. That is a bit expensive. But if e have a 5 day doubling time then we have 2^6 in a month, or only 64 cells. Is that enough to see or raise CA125. We do not know. How about once every 100 days, with 5 day doubling time. That is 2^20 cells or 1,000 times 1,000, and now we have a mass with CA125 effect and observable on ultrasound. But has it metastasized already? Good question.
But as with all such issues the insight is all too often in the question, not the answer. Ask the right question and you are brilliant.
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