It’s a bit tricky to do, but it’s possible.
When I render a tableView row, I also store all of the row’s display objects as references in the row:
row.title = display.newText( … )
row.icon = display.newImageRect( … )
etc. Then in your network.download() or network.request() call’s call back listener, you would need to get a reference to the row’s display group (which you added .title and .icon too) then you could display.remove() on the row’s. .icon entry and replace it with the new display.newImageRect() and replace the icon with it. If you’re using display.loadRemoteImage() it gives you a display object
I can’t give any more specifics because I don’t know your code structure well enough.
Rob