Updating control values from out of process..it is possible????

Hi folks: I have a simple question regarding out of process usage. It is possible to update the value of a label or textbox when I use out-of-process processing? I have included the following code snippet which is the actual one I am using in production (but very simplified for this example).  I have read elsewhere that I should use Delegates but that concept is very hard to follow up.
 Any suggestion or recommendation? Oh, btw, this a is legacy VS 2003 application so no Ajax :-<
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public class WebForm1 : System.Web.UI.Page
 {
  protected System.Web.UI.WebControls.Button btnProcess;
  protected System.Web.UI.WebControls.Label lblStatus;
 
  private void Page_Load(object sender, System.EventArgs e)
  {
   lblStatus.Text = "Ready for processing.& ...