The invention provides devices and methods for use in removing tissue samples from within a patient's body. The devices include instruments having shafts for cutting a path to a tissue mass, and an inflatable balloon or balloons attached to the shaft effective to dilate the path upon inflation in order to aid in the removal of tissue masses from within the body of a patient. The devices also include instruments having dilation plates that may be inserted into a path leading to a tissue mass to be removed, and the plates separated effective to dilate the path to aid in the removal of tissue masses. Methods include inserting a device into a path leading to a tissue mass, and inflating a balloon or separating plates, thereby widening the path, and removing the tissue mass. Such devices and methods find use, for example, in biopsy and in lumpectomy procedures.