I noticed that the nginx http proxy module by default does nothing with the Cache-Control request header that is sent by browsers.

Most browsers (I tested Crome and Firefox, but from my online research it showed that even Internet Explorer has the same behaviour) send a Cache-Control: no-cache header when the page requested is with Ctrl-F5 (as opposed to a normal F5 or page hit). I would like to configure my nginx caching proxy to take this request as an instruction to invalidate the cache, send a request to an upstream server, and send and cache that response.

Note that I'm NOT talking about the Cache-Control header sent from upstream webservers to the proxy. It's the Cache-Control request headers, not the response header.

Is there a configuration option that I've missed? I spent quite some time reading the documentation. Sadly the search terms that I can come up with (cache-control, proxy, etc) are too generic for what I want to express.