You may be having surgery to remove abnormal-appearing mouth lesions as part of standard care, so the study biopsies and tissue removal may be done at the same time as your surgery. After the surgeon has finished surgery and removed tissue from your mouth as part of your standard treatment, a portion of tissue (from both the abnormal-appearing and normal-appearing areas) that was already removed by the surgeon may be separated out from the main tissue specimen and separately evaluated. This is done so that the researchers can better compare the appearance and diagnosis at these sites to the images that were taken. In addition, a biopsy may be taken from the area of normal-appearing tissue from the opposite side of the mouth that was imaged with the FastEEM4 and/or POS probe(s), if the FastEEM4 and/or POS system(s) were used. If it is performed, this one biopsy of normal appearing tissue will be in addition to what is removed for standard care.