You are going to miss a few story points, including who Dark Samus is and the backstory of Phazon, but it's nothing major. You could easily read a summary of the first two games if this is an important issue to you. But the most important thing is just for you to play this wonderful game.
That said, if it's possible, I really do recommend playing the other two games as well. It'll just help Corruption have a greater impact on you. Plus, they're both damn great games.
But yeah, if you just want to play Corruption, don't be worried about missing out on the first two. It's nothing critical. You'll understand nearly everything and you'll have a ton of fun.