While you can't just make IE render on a canvas — too many things interact in unpleasant ways to make that impossible — you may well be able to use OpTcl to embed it in a window, which you can then put in a canvas if you choose.
Here's the informative example from that page:
package require optcl
optcl::new -window .htm {http://wiki.tcl.tk}
.htm config -width 800 -height 600
pack .htm
This will manufacture an instance of the COM object for handling an HTTP URL (in this case, http://wiki.tcl.tk) and embed it in a Tk widget (.htm). If you were going to embed it in a canvas, you'd do:
package require optcl
canvas .canv
optcl::new -window .canv.htm http://wiki.tcl.tk
.canv create window 0 0 -anchor nw -window .canv.htm
pack .canv
Well, that's the minimum. You'd really do a bit more (adding scrollbars, etc.)
There's a more extensive example on the Wiki too. (This doesn't appear to be a task for Tcom; that's designed to allow Tcl to interact with COM, but not really to allow Tk to embed widgets defined by it.) Be aware that I've not tested this on recent Windows systems or with recent versions of Tcl/Tk.