Dropping matched pair observations

[sanketshah07]

I have a dataset 'A' containing matched cases and controls.  The matched cases and controls exist as a single line observation. I have another dataset 'B' where I've identified certain controls from within A that I dont want to include in my study anymore. How can I drop the matched pair lines from A using the observations from B? (using SAS 9.4)

[ballardw]

Please provide examples of the input data sets, preferably as datastep code and what the desired output for those input sets would be.