Sentinel Lymph Node Biopsy in Early Stages of Oral Squamous Cell Carcinoma Using the Receptor-Targeted Radiotracer 99mTc-Tilmanocept

Sentinel lymph node biopsy in recurrent or secondary oral squamous cell carcinoma after previous neck dissection

OBJECTIVES

The aim of this retrospective study was to evaluate the potential of sentinel lymph node biopsy (SLNB) in patients with recurrent or a secondary oral squamous cell carcinoma (OSCC) without clinical signs of lymph node metastases (cN0), who were previously treated with a surgical approach.

PATIENTS AND METHODS

Retrospective analysis of all patients with cN0 recurrent or secondary OSCC, who were treated using SLNB after previous neck dissection. Endpoints were sentinel lymph node (SLN) detection rate, negative predictive value (NPV) and sensitivity.

RESULTS

A total of 17 patients with a mean age of 68.6 years were included. SLN were detected in 15 of 17 cases (detection rate: 88.2%). In seven patients (41.2%), a bilateral or contralateral lymph drainage of a unilateral carcinoma was found. Two patients (11.8%) demonstrated a positive SLN upon pathohistological analysis, which led to an upstaging. In one case, a non-SLN was positive, which is considered a false-negative result. The mean follow-up for all patients with histologically negative SLN including the patients without a detected SLN was 11.8 months (range: 0-31 months). Of these, one patient developed (isolated) neck recurrence after 12 months resulting in an overall NPV of 86.7% and a sensitivity of 50.0% for the SLNB as a neck staging procedure.

CONCLUSION

SLNB can improve the staging of patients with recurrent or secondary OSCC, who present with a history of a previous neck dissection. Further studies are required to demonstrate the oncological benefit of SLNB in this patient cohort.

A novel near-infrared EGFR targeting probe for metastatic lymph node imaging in preclinical mouse models

For the treatment of patients with oral squamous cell carcinoma (OSCC), the imaging of cervical lymph nodes and the evaluation of metastastic progression are of great significance. In recent years, the development of new non-radioactive lymph node tracers has been an area of intense research. Here, we report the synthesis, good biocompatibility, and in vivo evaluation of a new small molecule near-infrared (NIR) fluorescence probe by the conjugation of Lapatinib to S0456 (LP-S). We show that like Lapatinib, LP-S binds to the epidermal growth factor receptor (EGFR) resulting in high quality fluorescence imaging of metastatic lymph nodes in OSCC mouse models. After local injection of LP-S into the tumor, the lymphatic drainage pathway and lymph nodes can be clearly identified by NIR fluorescence imaging. Further, the LP-S probe shows higher contrast and longer retention in metastatic lymph nodes, allowing them to be differentiated from normal lymph nodes, and affording a new choice for fluorescence-guided surgery. Scheme. Chemical synthesis and application of EGFR targeting probe LP-S for imaging of metastatic lymph nodes (mLNs) in OSCC.

99mTc-Tilmanocept performance for sentinel node mapping in breast cancer, melanoma, and head and neck cancer: a systematic review and meta-analysis from a European expert panel

PURPOSE

Although multiple radiopharmaceuticals are currently available for sentinel node (SN) biopsy, 99mTc-tilmanocept is of particular interest due to its low molecular weight and specific binding capability for the mannose receptors of lymphatic reticuloendothelial cells. In the current systematic review and meta-analysis, we aimed to provide an update from a European expert panel on the performance of 99mTc-tilmanocept for SN biopsy.

METHODS

A systematic literature search of the PubMed/Medline and Embase databases was performed to identify studies on the use of 99mTc-tilmanocept for SN identification in oncological patients. The articles' methodological quality was assessed before inclusion. The pooled estimates of the pre-/intraoperative detection rates (DR; proportion of patients with ≥ 1 SN identified) and/or pN + sensitivity (SN + /pN + patients ratio), with 95% confidence intervals (CIs), were calculated for breast cancer, melanoma, and head and neck cancer.

RESULTS

Twenty-four articles were included in the systematic review, and twenty-one provided data for the meta-analysis. According to data availability, the 99mTc-tilmanocept-estimated pooled preoperative and intraoperative DRs were 0.94 (95%CI, 0.88-1.01) and 0.99 (0.98-1.00) for breast cancer, 0.98 (0.96-0.99) and 1.00 (0.99-1.00) for melanoma, and 0.97 (0.93-1.02) and 0.99 (0.96-1.01) for head and neck carcinoma. Finally, the pooled sensitivity for nodal metastasis in melanoma was 0.97 (95% CI, 0.92-1.03).

CONCLUSION

99mTc-tilmanocept is a promising radiotracer for SN mapping in patients with breast cancer, melanoma, or head and neck cancer. We strongly believe that multicenter trials are still needed to assess if 99mTc-tilmanocept is superior to other radiotracers used in clinical routine.

Management of the Contralateral Neck in Unilateral Node-Positive Oral Squamous Cell Carcinoma

INTRODUCTION

In lateralized oral squamous cell carcinoma (OSCC) with ipsilateral cervical lymph node metastasis (CLNM), the surgical management of the unsuspicious contralateral neck remains a matter of debate. The aim of this study was to analyze this cohort and to compare the outcomes of patients with and without contralateral elective neck dissection (END).

MATERIAL AND METHODS

A retrospective analysis of patients with lateralized OSCC, ipsilateral CLNM (pN+) and contralateral cN0-stage was performed. Patients were divided into two groups according to the surgical management of the contralateral neck: I: END; and II: no END performed. Adjuvant radiotherapy was applied bilaterally in both groups according to individual risk.

RESULTS

A total of 65 patients (group I: 16 (24.6%); group II: 49 (75.4%)) with a median follow-up of 28 months were included. Initially, there was no case of contralateral CLNM after surgery. During follow-up, 6 (9.2%) patients presented with recurrent CLNM. In 5 of these cases (7.7%), the contralateral neck (group I: 3/16 (18.8%); group II: 2/49 (4.1%)) was affected. Increased ipsilateral lymph node ratio was associated with contralateral CLNM (p = 0.07). END of the contralateral side showed no significant benefit regarding OS (p = 0.59) and RFS (p = 0.19).

CONCLUSIONS

Overall, the risk for occult contralateral CLNM in patients with lateralized OSCC ipsilateral CLNM is low. Our data suggest that END should not be performed routinely in this cohort. Risk-adapted radiotherapy of the contralateral neck alone seems to be sufficient from the oncological point of view.