DTS and SQL Server

Is it possible to run Data Transformation Services (DTS) on demand by having a user click on a button in an application with SQl Server?
I am creating a project in vb.net where I want the user to be able to hit an "update" button and data will be updated to my SQL Server table by DTS.

Also is it possible to check for duplicate entries before running DTS? E.g I want to append to my table but exclude duplicate entries UNLESS the data has changed for that entry.>>Is it possible to run Data Transformation Services (DTS) on demand

Yes. http://msdn.microsoft.com/msdnmag/issues/04/01/WebQA/

>>Also is it possible to check for duplicate entries before running DTS

Make this a step in your dts package