The necessity of level IIb dissection for clinically negative neck oral squamous cell carcinoma

Influence of Site, Size, Depth of Invasion and Histologic Grading on the Occurrence of Cervical Level IIb Metastasis and Extranodal Extension in Clinically N0 Neck of Patients with OSCC: A Single Center Retrospective Analysis

Background

Depth of Invasion ≥ 4 mm, T stage and primary site with more than 20% chances for occult metastasis are currently the accepted indications for elective neck dissection. Nodal metastasis decreases survival by 50%. ENE further reduces the prognosis. Dissection of level IIb lymph nodes in clinically N0 neck does not improve survival.

Methods

A total of 320 patients were evaluated. Binary and multiple logistic regression and chi-square test were used for data analysis. ROC curve with Youden's J index was used to set up a cutoff value for DOI. The predictor variables were site, size, grading and depth of invasion of primary tumor. Incidence of level IIb metastasis and ENE were the outcomes.

Results

The study revealed a significant association and risk stratification between primary tumor characteristics with the occurrence of ENE. The cutoff value for DOI predicting ENE was 12.5 mm. Tumors of the oral tongue were an independent risk factor for level IIb metastasis.

Discussion

Size of primary tumor, DOI, tumors of the mandibular alveolus and poor grading are independent risk factors for ENE. Isolated metastasis to level IIb rarely occurs in the absence of concomitant level IIa metastasis. Size, DOI and grading were significantly associated with level IIb metastasis. However, only tumors of the oral tongue were independent risk factor.

Prevalence of occult level 2b nodal metastases in cN0 squamous cell carcinoma of the oral cavity: A systematic review and meta-analysis

Elective neck dissection of levels I, II and III is being increasingly used for detecting occult node metastases in patients with oral squamous cell carcinoma (OSCC) and clinically negative neck (cN0). The most frequent potential long-term complication of this procedure is shoulder dysfunction, because of micro- or macroscopic damage to the spinal accessory nerve (SAN). In particular, many studies have reported an association between SAN damage and dissection of level 2b. Furthermore, level 2b dissection is a technically demanding and time-consuming procedure. Our study aims to clarify whether level 2b sparing in cN0 patients with OSCC can be oncologically justifiable. The PubMed, Cochrane and Scopus databases were searched by three different authors for articles on this topic. The primary endpoint of the meta-analysis was the overall prevalence of occult metastases in cervical level 2b nodes in patients with OSCC and clinically negative neck. The meta-analysis was performed using R version 4.0.1. A total of 13 studies and 937 patients were included. The cumulative rate of occult nodal metastases in level 2b was 0.8% (n = 937, 95% CI: 0.1% - 2.2%, τ² = 0.004). No isolated level 2b metastases was found among the patients with positive level 2b, and in the six studies that reported this association, all patients with nodal disease in level 2b had a positive level 2a. This meta-analysis highlights how level 2b can be safely spared in supraomohyoid neck dissection (SOHND) of patients with OSCC and clinically negative neck, reducing the risk of postoperative shoulder dysfunction.

How is neck dissection performed in Oral and Maxillofacial Surgery? Results of a representative nationwide survey among university and non-university hospitals in Germany

Introduction

Neck dissection (ND) is a surgical procedure addressing cervical lymph nodes and metastases in patients with oral squamous cell carcinoma (OSCC). The aim of this study was to analyze clinical decisions regarding indications and variations of ND in Oral and Maxillofacial Surgery (OMFS) in Germany.

Material and methods

A nationwide survey of the German Association of Oral and Maxillofacial Surgery was performed using dynamic online questionnaires including 38 questions. Data about oncological centers, case numbers, and staging procedures were collected. Relevant aspects, such as inclusion of level IIb and levels IV and V to ND, uni- vs. bilateral ND, and the influence of extra-nodal extension (ENE) of metastases on extension of ND were evaluated.

Results

Eighty-four OMFS of university and non-university hospitals participated in the study (responding rate 21.4%). Sixty-six (78.57%) stated to work at certified cancer centers and 53.57% of the hospitals treated between 50 and 100 OSCC cases per year. CT and/or MRI of the head and neck was performed in most of the staging procedures. Level IIb was included by 71 (93.42%) of the participants in selective ND. Levels IV and V were included by 53 (69.74%) in node-positive neck. In solitary ipsilateral metastases (ENE−), 49 participants (62.82%) stated to perform exclusively an ipsilateral ND and 40 (51.95%) stated to perform only an ipsilateral ND in ENE+.

Conclusion

This study demonstrated a high rate of certified cancer centers in Germany showing differences regarding staging procedures, indications, and extension of ND, especially in increasingly complex cases.

Clinical relevance

Clinical decisions regarding ND are dependent on case-individual aspects and must be decided individually.