A method for removing at least part of a brain tumor may first involve contacting a forward-facing tissue cutter disposed at the distal end of a tissue removal device with the brain tumor. The tissue removal device may include a shaft having a diameter no greater than about 10 mm, and in some embodiments the tissue cutter does not extend laterally beyond the diameter of the shaft. The method may next involve cutting tissue from the brain tumor, using the tissue cutter. The method may then involve moving the cut tissue through a channel of the shaft in a direction from the distal end of the tissue removal device toward a proximal end of the device.