SA1 - Analysis of Virtual Surgical Planning and Surgical Margins in Malignant Tumor Surgery

Abstract: Virtual Surgical Planning (VSP) for oncological reconstruction of head and neck tumors has been shown to decrease operating time and flap ischemia time, along with improving the geometry, as compared to the conventional method for resection and reconstruction. 1 2 With the planning and fabrication of the custom plates and cutting guides, it may take over 2 weeks to be able to take the patient for surgical intervention. The purpose of this analysis was to see if this delay in the surgery would result in compromised oncological margins during the resection of the tumor.A single-center retrospective analysis was performed with chart reviews of patients undergoing VSP-planned resection of an oral malignant tumor along with immediate reconstruction. From March 2019 to December 2023. Operative and pathological reports were reviewed to determine our primary outcome, which is the oncological margin status. Other data collected includes clinical and pathological staging, time from initial diagnosis to surgery date, and the microvascular flap used for the reconstruction of the surgical defect.VSP was completed for 50 patients who subsequently underwent resection of a malignant oral tumor, followed by immediate reconstruction during the study timeline. A total of 44 patients met the inclusion criteria and had sufficient medical data. The average age of the patients is 64 years. There are 31 males and 13 females. Positive margins were found in six patients (12%), while another 26 patients (52%) had a close margin ( < 5 mm). Clear margins (5 mm+) were observed in 14 patients (28%). The cut off value of 41 days for CT to Sx interval showed 100% Sensitivity and 89.5% Specificity for Positive Margins.VSP is an indispensable tool for reducing operating time, flap ischemia time, and the geometry of the reconstruction of the surgical defect. Our results show that 12% of patients suffered from positive margins, with another 52% of our patients having close margins. Careful consideration must be taken as the delay in surgery due to prosthesis fabrication may result in compromised oncological margins.1 Chang EI, Jenkins MP, Patel SA, Topham NS. Long-Term Operative Outcomes of Preoperative Computed Tomography-Guided Virtual Surgical Planning for Osteocutaneous Free Flap Mandible Reconstruction. Plast Reconstr Surg. 2016 Feb;137(2):619-23.2 Wang YY, Zhang HQ, Fan S1, Zhang DM, Huang ZQ, Chen WL, Ye JT, Li JS. Mandibular reconstruction with the vascularized fibula flap: comparison of virtual planning surgery and conventional surgery. Int J Oral Maxillofac Surg. 2016 Nov;45(11):1400-1405.

Fig1. Association of Margin with Sex, Site and Stage
Table1. Association of Margins with Sex, Site and Stage
Fig2. ROC Analysis to predict Positive Margin Cases