Intraoperative Ultrasound for the Management of Oral Tongue Cancer: a Systematic Review and Meta-Analysis.

Objective: To evaluate for correlation between intraoperative ultrasound (IOUS)-measured tumor thickness (TT) (uTT) and histopathological TT (hTT), and to compare IOUS-assisted resection with conventional resection in patients with oral tongue cancers.

Data sources: Ovid MEDLINE (1946-2023), Embase.com (1947-2023), and Web of Science (All Databases 1900-2023).

Review methods: Inclusion criteria were the use of IOUS for the management of oral tongue cancer. Studies that did not report quantitative data were excluded. Additionally, studies that were not contributory to meta-analysis, or a narrative analysis of pooled results were excluded. Selection was carried out by 2 reviewers. A total of 2417 studies were initially identified, with 12 ultimately being included in this review, and 7 included in the meta-analysis. Data were extracted by 2 investigators and were pooled using a random-effects model.

Results: Our meta-analysis reveals a pooled correlation coefficient of 0.92 (95% confidence interval: 0.80-0.96) for studies comparing uTT to hTT. Studies comparing IOUS-assisted resection to conventional resection found IOUS-assisted resection yielded wider nearest margins in all studies reporting this outcome.

Conclusion: IOUS reliably measures TT, similarly to that of histopathology measurement. IOUS-assisted resection, which allows the surgeon to view the deep extent of tumor invasion, may increase closest radial margin distance compared to conventional resection. IOUS-assisted resection may represent a more reliable approach to achieving clear margins than conventional resection.