Purpose: Sentinel lymph node (SLN) biopsy has proven to reliably stage the clinically negative neck in early-stage oral squamous cell carcinoma (OSCC). [^99mTc]Tc-tilmanocept may be of benefit in OSCC with complex lymphatic drainage patterns and close spatial relation to SLNs. Methods: A prospective within-patient evaluation study was designed to compare [^99mTc]Tc-tilmanocept with [^99mTc]Tc-nanocolloid for SLN detection. A total of 20 patients with early-stage OSCC were included, who underwent lymphoscintigraphy with both tracers. Both lymphoscintigraphic images of each patient were evaluated for SLN detection and radiotracer distribution at 2–4 h post-injection. Results: The injection site’s remaining radioactivity was significantly lower for [^99mTc]Tc-tilmanocept (29.9%), compared with [^99mTc]Tc-nanocolloid (60.9%; p < 0.001). Radioactive uptake in SLNs was significantly lower for [^99mTc]Tc-tilmanocept (1.95%) compared with [^99mTc]Tc-nanocolloid (3.16%; p = 0.010). No significant difference was seen in SLN to injection site ratio in radioactivity between [^99mTc]Tc-tilmanocept (0.066) and [^99mTc]Tc-nanocolloid (0.054; p = 0.232). A median of 3.0 and 2.5 SLNs were identified with [^99mTc]Tc-tilmanocept and [^99mTc]Tc-nanocolloid, respectively (p = 0.297). Radioactive uptake in higher echelon nodes was not significantly different between [^99mTc]Tc-tilmanocept (0.57%) and [^99mTc]Tc-nanocolloid (0.86%) (p = 0.052). A median of 2.0 and 2.5 higher echelon nodes was identified with [^99mTc]Tc-tilmanocept and [^99mTc]Tc-nanocolloid, respectively (p = 0.083). Conclusion: [^99mTc]Tc-tilmanocept had a higher injection site clearance, but at the same time a lower uptake in the SLN, resulting in an SLN to injection site ratio, which was not significantly different from [^99mTc]Tc-nanocolloid. The relatively low-radioactive uptake in SLNs of [^99mTc]Tc-tilmanocept may limit intraoperative detection of SLNs, but can be overcome by a higher injection dose.

Sentinel lymph node biopsy (SLNB) is a diagnostic staging procedure that aims to identify the first draining lymph node(s) from the primary tumor, the sentinel lymph nodes (SLN), as their histopathological status reflects the histopathological status of the rest of the nodal basin. The routine SLNB procedure consists of peritumoral injections with a technetium-99m [^99mTc]-labelled radiotracer followed by lymphoscintigraphy and SPECT-CT imaging. Based on these imaging results, the identified SLNs are marked for surgical extirpation and are subjected to histopathological assessment. The routine SLNB procedure has proven to reliably stage the clinically negative neck in early-stage oral squamous cell carcinoma (OSCC). However, an infamous limitation arises in situations where SLNs are located in close vicinity of the tracer injection site. In these cases, the hotspot of the injection site can hide adjacent SLNs and hamper the discrimination between tracer injection site and SLNs (shine-through phenomenon). Therefore, technical developments are needed to bring the diagnostic accuracy of SLNB for early-stage OSCC to a higher level. This review evaluates novel SLNB imaging techniques for early-stage OSCC: MR lymphography, CT lymphography, PET lymphoscintigraphy and contrast-enhanced lymphosonography. Furthermore, their reported diagnostic accuracy is described and their relative merits, disadvantages and potential applications are outlined.

Purpose: Evaluating the Crystal Cam handheld gamma-camera for preoperative and intraoperative sentinel lymph node (SLN) localization in early-stage oral cancer. Methods: The handheld gamma-camera was used complementary to conventional gamma-probe guidance for intraoperative SLN localization in 53 early-stage oral cancer patients undergoing SLN biopsy. In 36 of these patients, a blinded comparison was made between preoperative handheld gamma-camera and lymphoscintigraphy outcomes. Of those, the reliability for marking the SLN’s location using both handheld gamma-camera and a ⁵⁷Co-penpoint marker was evaluated in 15 patients. Results: In the entire cohort, the handheld gamma-camera preoperatively detected 116/122 (95%) of SLNs identified by lymphoscintigraphy. In those patients where the observer was blinded for lymphoscintigraphy (n = 36), 71/77 (92%) SLNs were correctly identified by handheld gamma-camera. Overlooked SLNs by handheld gamma-camera were mainly located near the injection site. The SLN’s marked location by handheld gamma-camera and ⁵⁷Co-penpoint marker was considered accurate in 42/43 (98%) SLNs. The intraoperative use of the handheld gamma-camera led to the extirpation of 16 additional ‘hot’ lymph nodes in 14 patients, 4 of which harbored metastases, and prevented 2 patients (4%) from being erroneously staged negative for nodal metastasis. In those with follow-up ≥ 24 months or false-negative outcomes < 24 months following SLNB, a sensitivity of 82% and negative predictive value of 93% was obtained. Conclusion: The Crystal Cam handheld gamma-camera offers reliable preoperative and intraoperative SLN localization and might reduce the risk of missing a malignant SLN during surgery. Detecting SLNs near the injection site by handheld gamma-camera remains challenging.

Purpose: Arytenoid resection is a well-known intervention to improve glottic airway. Superomedial partial arytenoidectomy (SPA) can also be used for voice improvement by correcting posterior glottic insufficiency in patients with an obstructing anteromedially prolapsed arytenoid. Posterior glottic insufficiency can be difficult to address and traditionally involves challenging arytenoid repositioning procedures. This study aimed to compare postoperative functional voice outcomes in patients who underwent SPA to pre-operative voice status. Second, consequences of concomitant injection augmentation in patients who underwent SPA were studied. Additionally, presenting the surgical technique.Methods: In this retrospective cohort study, pre-operative and postoperative clinical data of patients who underwent SPA between 2004 and 2018 were analyzed. Both short- and long-term voice outcomes were assessed using Voice Handicap Index (VHI) and maximum phonation time (MPT). Pre- to postoperative assessment changes (delta:δ) were applied to multivariate analyses.Results: A total of 105 patients were included, of which 91 had hemilaryngeal immobility, 25 had undergone previous phonosurgical procedures and 45 received concomitant injection augmentation. Patients who underwent SPA had significant improvement of VHI and MPT. In 81% of our population, laryngeal framework surgery was avoided. Multivariate analyses showed significantly improved short-term voice outcomes in patients who received injection augmentation concomitantly to SPA. Finally,δMPT was a significant predicting factor regarding additional procedures in patients who underwent SPA.Conclusion: SPA is a safe and efficient procedure for voice improvement in patients with posterior glottic insufficiency due to an obstructing anteromedially prolapsed arytenoid. We recommend performing this procedure combined with injection augmentation.

Sentinel lymph node biopsy (SLNB) has proven to reliably stage the clinically negative neck in early-stage oral squamous cell carcinoma (OSCC). The 10%-rule, used to define sentinel lymph nodes (SLN) intraoperatively, states that an SLN is defined by gamma counts that are at least 10% of the hottest harvested lymph node (LN). However, this intraoperative rule has not yet been adequately evaluated for early-stage OSCC. This study aims to evaluate the 10%-rule intraoperatively and explore possibilities for redefining this criterion. A single center retrospective study was performed between 2014 and 2023. Patients (n = 66) with clinically node-negative OSCC (cT1-3N0) and positive SLNB were included in this study. Radioactivity of all harvested LNs were measured ex-vivo. Metastatic LNs were assessed for complying with the 10 %-rule. The accuracy of alternative thresholds was evaluated. If multiple positive SLNs on one side of the neck were found, the hottest positive SLN on that side was considered the LN accountable for upstaging the corresponding neck side from N0 to N+. A total of 233 LNs were harvested, of which 98 contained metastases and 190 met the 10%-rule. Of these metastatic LNs, 70 were accountable for upstaging the side of the neck. The 10%-rule correctly staged 69 of 70 metastatic sides of the neck. By increasing the intraoperative cut-off point to 20%, 68 of 70 metastatic sides of the neck were correctly staged and 18 LNs (172 vs. 190) were not defined as SLN. Applying the 10%-rule to each side of the neck increased detection of one metastatic LN. However, this LN was not accountable for upstaging that side of the neck. The 10%-rule in SLNB applies to patients with OSCC and effectively identifies metastatic SLNs intraoperatively. Applying the 10%-rule per neck side must be considered. Increasing the threshold percentage is not advisable.