It's not just Windows XP that reaches support end of life next April on Patch Tuesday, but Office 2003 as well. This was an extremely popular version of Office, and running it without security patches will be dangerous.
Many are outraged that Windows XP will soon reach end-of-life for support and no longer receive security updates, but it gets worse. On the same day, Patch Tuesday, April 8, 2014, Office 2003 and all its constituent applications, will also receive their last updates.
Read more at: Office 2003 soon to lose support too | ZDNet