Help with breaking cache?

I’m currently using memcache

Let’s assume I have a blog post entry.

So I’ll cache that so I have the tags, categories, metadata, etc. all together and fetchable via the cache.

Then I’ll have a “listing of the latest entries” which I would also cache.

So, say a blog post shows up in the latest entries… and I update the title. I can break that entry’s cache, but how would I update it within the list of the latest items?

I’ve never used memcache before, but i’ve dabble with caching.

Would it not be better to cache the post and directly related content (ie: tags) separately then import the cache into the content area as opposed to caching the entire page?
This method would allow everything else to be dynamic and up-to-date.

I only cache what is going to change on a very rare occasion, if at all, so things like latest lists, comments, etc are not cachable IMHO