Intraoperative cytological examination of bone medullary. A useful technique to predict the extension of bone invasion in segmental mandibulectomy

Aim: The main of the present report is to evaluate the utility of intraoperative cytological analysis of medullary bone to predict the extension of bone infiltration in segmental mandibulectomy. Materials and method: Between the years 2016 and 2018, a total of 17 previously untreated patients with squamous cell carcinoma of the oral cavity underwent a segmental mandibular resection and intraoperative cytological analysis of the bone medullary at Virgen de las Nieves University Hospital (HUVN). The results of the intraoperative cytological analysis were compared with the result of the postoperative histopathological examination and sensitivity, specificity, positive predictive value, and negative predictive value of the test were calculated. Results: Cytological analysis was positive in three patients and the bone resection was consequently extended. All the extensions of these bone margins were clean following the postoperative histological examination. However, two other patients previously classified as clean with intraoperative cytological analysis of bone medullary presented infiltration of bone margins postoperatively. The protocol demonstrated a high negative predictive value (85,7%). The positive predictive value, sensitivity, and specificity were 33,3%, 33,3%, and 85,7% respectively. Conclusion: Intraoperative cytological analysis of bone medullary could represent an easy, fast, reliable and inexpensive method to reduce the rate of r1 surgeries attributable to the infiltration of the bone margin. This may have a positive impact on overall survival without increasing the duration and the iatrogenicity of surgery.