That is precisely the problem with tests of this kind. If a rare disease like pancreatic cancer is screened, the test should be very accurate to avoid unnecessary false positives. Since the layperson does not understand this and may happily buy the test, there is still that small, somewhat unethical market niche.
The incidence of pancreatic cancer in 50-year-olds is approximately 10 / 100,000. If this group is tested with 78% sensitivity and 92% specificity, 8 cancer cases will be found, and at the same time, approximately 8,000 false positives will be obtained. So, to find 8, unnecessary anxiety and the need for further examinations are caused for 8,000 patients.
Evidence would be needed that more targeted screening benefits life expectancy. This requires large, expensive studies, and we are very far from that.