Sentinel lymph node biopsy in oral–oropharyngeal squamous cell carcinoma: standards, new technical procedures, and clinical advances

Abstract

To provide substantial coverage and critical appraisal of standards as well as new technical procedures and clinical advances concerning sentinel lymph node biopsy (SNB) in oral squamous cell carcinoma (OSCC). The MEDLINE database was searched via the PubMed interface up to January 2019 for the following MeSH heading: “sentinel lymph node biopsy” and “squamous cell carcinoma of head and neck”. SNB exists as an alternative to elective neck dissection (END) in OSCC. Pre-surgical planar lymphoscintigraphy with intra-operative hand-held gamma probe allows using SNB. Furthermore, the contribution of pre-surgical SPECT/CT improves the sentinel lymph node (SLN) roadmap in sites that are closer to the injection site. Portable gamma camera and freehand SPECT are not yet routine clinical practice, but can further improve intra-operative SLN detection. However, the difficulty in detecting SLNs located closer to the injection site persists. SNB with combined radioactive and near-infrared fluorescence guidance is an attractive option for improving spatial resolution of radio-guided techniques while maintaining depth penetration. Numerous studies have demonstrated that SNB can be proposed for accurate histopathological staging of the neck and the guidelines support the introduction of SNB as an alternative to END in T1/T2 N0 OSCC patients. New hybrid imaging techniques, which are offering new possibilities to assist clinicians and surgeons in localizing the site of uptake in sentinel node detection, need to be confirmed in ongoing and future clinical trials. In the future, the integration of new PET tracers could continue along the route mapped out in SNB.