There are several solutions:
1) set the page to "do not cache" (edit page properties). But this will prevent indexed_search to search that site, which is probably ok.
2) add a hook, which clears the cache for that site (have a look at t_c_emain.html#a339ac0da0377744f512bf790e79f5563">http://api.typo3.org/typo3v4/current/html/classt3lib_t_c_emain.html#a339ac0da0377744f512bf790e79f5563) not that easy
3) add &no_cache=1 and set cache-time of the page to a few minutes (so the page will be indexed via indexed_search)
4) Write an AJAX Script (eID) which request the newest News Records which are not show yet.
I think, it depends on your needs which way to go. 1) is the quickest from developer point of view, but the worst in the performance view. 2) is harder for the developer, perhaps better for the performance, 3) something in between. 4) is perhaps a better solution if there are a lot of users