Can the Tridion Core Service be notified of data changes?

I use the basic Facade service for some lazy programmers who don’t want to change their coding style (including me) and want to implement an object cache, which obviously leads to the big question of “how long and how much should I cache”.

The ideal answer is caching forever, unless the data changes.

Is there a way (through some WCF event) to implement a "listener" for data changes that can be used to remove items from their cache?

By the way, I use my own ObjectCache (MemoryCache) .NET with a 1-minute rolling cache policy.

Thank,

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