Fig. 1.

Representative case of segmental mandibulectomy with intraoperative evaluation of bone marrow. a Routine frozen section preparation of bone marrow. All intraoperative bone marrow biopsies contained bony spicules (right upper corner). Bony spicules may damage microtome blade, create uneven/“scratched” sections, and lift the coverslip creating pockets of air (right lower corner). However, fragments of squamous cell carcinomas can still be recognized (left half of the image), H&E, 200×. b Permanent H&E preparation of the frozen section remnant. Frozen section remnants can be processed without decalcification and serve as a control for intraoperative bone marrow evaluation, H&E, 200×. c Representative field of a final decalcified cross-sectional shave bone margin with squamous cell carcinoma, H&E, 100×