Intraoperative Margin Control in Transoral Approach for Oral and Oropharyngeal Cancer

Abstract

Objectives Piecemeal resection provides an innovative conceptual tool for margins surveillance because it entails the intraoperative evaluation of the whole resection margins and not just sample points, which should result in a better control of deep margins compared to en bloc resection. Although it is recognized that the intraoperative use of narrow band imaging (NBI) results in a better control of superficial margins, in this exploratory study we investigated whether NBI and piecemeal resection could be used in combination to improve margin control at both superficial and deep levels. Because piecemeal resection is based on frozen section analysis, we wanted to verify its reliability compared to definitive histological examination. Methods The status of resection margins in a group of patients with oral and oropharyngeal cancers treated with NBI and laser CO2 piecemeal resection (group 1) was compared with that of an historical group of patients (group 2) treated with NBI and conventional en bloc resection. In group 1, sensitivity, specificity, and positive and negative predictive values were used to verify the rate of concordance between frozen section and definitive histology. Results The difference between deep positive margins in the two groups was statistically significant (P = 0.042). The high sensitivity and specificity (94.6% and 94.7%, respectively) of frozen section analysis also demonstrated its reliability in the examination of larger samples corresponding to the whole margin. Conclusion Even if our findings are limited by the small number of patients, we are confident that the combined use of NBI and piecemeal resection could represent an attractive surgical strategy to improve margin control. Level of Evidence 2b Laryngoscope, 129:1810–1815, 2019

Novel Approaches in Surgical Management: How to Assess Surgical Margins

“…This could be explained by the fact that sampling on the surgical specimen leads the surgeon to address the most critical margin relative to the palpable mass, whereas analysis of the surgical bed requires inferring the initial situation of the tumor. However, some authors have reported that circumferential sampling of the surgical bed has an almost excellent negative predictive value, though with suboptimal positive predictive value [43]. Irrespective of the specific technique employed to sample tissue to be sent for frozen section analysis, a metaanalysis demonstrated that achieving negative margins by extending the resection based on a positive frozen section does not equate to an initially negative margin, nor does it significantly increase the local control rate [44].…”

Frozen sections and complete resection in oral cancer surgery

“…Clear surgical margins with oral squamous cell carcinoma (OSCC) are of primary importance as positive surgical margins are related to local recurrence risk and survival (Weijers, Snow, Bezemer, van der Wal, & van der Waal, ) and represent one of the adverse features requiring postoperative adjuvant treatments (NCCN, ), which increase costs and toxicity. The issue of complete tumour resection is even more important during transoral surgery (TOS), a surgical approach completely performed through the mouth and minimising injury to healthy tissue (Tirelli, Boscolo Nata, Gatto, et al, ). The surgical field in TOS is narrower compared to the classical open approaches (transmandibular, pull through), and complete tumour exposure and margin control may become challenging.…”

Post-operative outcomes of different surgical approaches to oropharyngeal squamous cell cancer: a case-matched study

“…Transoral laser microsurgery is a step-by-step resection in which the surgeon can cut through the tumour to inspect the boundary between normal and diseased tissue under microscopic magnification in a more accurate way compared with conventional surgery. 31 Furthermore, the transoral laser microsurgery philosophy entails meticulous margin mapping, guided by frozen section, 32 until complete ('R0' microscopically margin-negative) resection is attained. This can be achieved thanks to the low thermal damage of the carbon dioxide laser to tissue, 33 and the close co-operation between the surgeon and the pathologist, which facilitates reallocation of a positive margin for subsequent intra-operative re-resection.…”