Yes it is possible, but there is no circuit for the leds only holes in the pcb for them so you will have to use wires to create your own circuit and tie it straight to the usb 5v line with appropriate resistor. This means it will be on always, or you could add in a small toggle switch near the bottom rear of the casebody since there is room under pcb to have it select on/off. Anything more would require quite a bit more work if you want anything fancy like brightness level and such.
Smaller section of led like on wasd is much easier, can just tie it to esc lock or something.