Page Title for Text/Plain Document

I am using a GenericHandler to print information out as text/plain in the client browser.
Currently when I run the app, the title-bar says something like http://localhost:3014/myApp/ShowReport?id=123456
I do need to modify the actual url. I just want a user-friendly title in the browser tab that is more descriptive of the report they are looking at. So if the user selects to view report TI591, then TI591 will appear in the browser tab.
Is there header information I can add? If so, how do I go about adding that?
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