Extent of neck dissection for patients with clinical N1 oral cancer

Radiological assessment of the dissection area in supraomohyoid neck dissection

PURPOSE

The current supraomohyoid neck dissection (SOHND) is performed above the omohyoid muscle to dissect levels I, II, and III in the levels of cervical lymph nodes. However, the anatomical boundary between levels III and IV is the inferior border of the cricoid cartilage. We investigated the anatomical relationship between the omohyoid muscle and cricoid cartilage using contrast-enhanced CT (CE-CT) images to assess the validity of the current SOHND.

METHODS

CE-CT images of the head and neck regions in patients were reviewed. The patients were divided into two groups: "malignant tumors" and "others". The vertebral levels corresponding to the positions of anatomical structures such as the intersection of the omohyoid muscle and internal jugular vein (OM-IJ), and the inferior border of the cricoid cartilage (CC), were recorded.

RESULTS

The OM-IJ was located around the seventh cervical to the first thoracic vertebra. There was a significant difference between the malignant tumor and others groups in females (p = 0.036). The CC was located around the sixth to seventh cervical vertebrae. There was a significant sex difference in each group (malignant tumor: p < 0.0001; others: p = 0.008). Both sexes tended to have lower OM-IJ than CC, and females had significantly lower OM-IJ than males.

CONCLUSION

This study provides clear anatomical evidence showing the difference between the SOHND dissection area and levels I, II, and III. It could be considered that in most cases SOHND invades level IV, not just levels I, II, and III, especially in female patients.

Ultrasound Characteristics of Metastatic Occult Cervical Lymph Nodes in Early Tongue Cancer

Introduction: Identification of occult lymph node metastasis is challenging in early tongue cancers. We conducted a prospective study to determine the most characteristics ultrasonic feature suggestive of metastatic node. Material and Methods: A preliminary study based on feasibility was planned on twenty five patients with squamous cell carcinoma of tongue (T1,T2) and N0 neck underwent ultrasonography of neck. The results of each ultrasonic parameters (size, shape, echogenicity, margin and hilum) for suspicion were analysed. Pathologic evaluation of surgical resected neck specimen served as the reference standard. Results: USG yielded sensitivity and specificity by size, by morphology, either size or morphology are 50.0% and 87.5%, 75.0% and 87.5, 75.0 and 83.3% respectively. Morphology alone has highest negative predictive value (NPV:91.3%) with accuracy of 84.3%. Conclusion: Morphology of the lymph node had highest sensitivity and specificity with highest negative predictive value correlating with its metastatic nature.

Nodal Metastasis in Surgically Treated Oral Cavity Squamous Cell Carcinoma

INTRODUCTION

Management of the neck in oral cavity squamous cell carcinoma (OCSCC) is essential to oncologic control and survival. The rates of lymph node metastasis (LNM) vary based on oral cavity tumor site and stage and influence treatment decisions. The aim of this paper was to describe clinical LNM for different tumor subsites and stages of surgically managed OCSCC.

METHODS

We conducted a retrospective analysis of 25,846 surgically managed OCSCC patients from the National Cancer Database (NCDB) stratified by tumor subsite and clinical T-stage. For cN + patients, rates of pathologic LNM and absence of pathologic LNM were determined. For cN0 patients, outcomes included the rates of elective neck dissection (END) and occult LNM and predictors of occult LNM determined by a multivariable logistic regression model.

RESULTS

A total of 25,846 patients (59.1% male, mean age 61.9 years) met inclusion criteria with primary tumor sites including oral tongue (50.8%), floor of mouth (21.2%), lower alveolus (7.6%), buccal mucosa (6.7%), retromolar area (4.9%), upper alveolus (3.6%), hard palate (2.7%), and mucosal lip (2.5%). Among all sites, clinical N+ rates increased with T-stage (8.9% T1, 28.0% T2, 51.6% T3, 52.5% T4); these trends were preserved across subsites. Among patients with cN + disease, the overall rate of concordant positive pathologic LNM was 80.1% and the rate of discordant negative pathologic LNM was 19.6%, which varied based on tumor site and stage. In the overall cohort of cN0 patients, 59.9% received END, and the percentage of patients receiving END increased with higher tumor stage. Occult LNM among those cN0 was found in 25.1% of END cases, with the highest rates in retromolar (28.8%) and oral tongue (27.5%) tumors. Multivariable regression demonstrated significantly increased rates of occult LNM for higher T stage (T2 OR: 2.1 [1.9-2.4]; T3 OR: 3.0 [2.5-3.7]; T4 OR: 2.7 [2.2-3.2]), positive margins (OR: 1.4 [1.2-1.7]), and positive lymphovascular invasion (OR: 5.1 [4.4-5.8]).

CONCLUSIONS

Management of the neck in OCSCC should be tailored based on primary tumor factors and considered for early-stage tumors.

Extent of Neck Dissection and Cervical Lymph Node Involvement in Oral Squamous Cell Carcinoma

Introduction

Tumor resection combined with neck dissection (ND) or radiotherapy are established methods for the treatment of patients with oral squamous cell carcinoma (OSCC). However, the extent of ND can lead to postoperative complications. Therefore, for the first time, this study aims to identify lymph node involvement in OSCC performed in a bilateral systematic approach based on oncologic board meetings relying on presurgical magnetic resonance imaging (MRI) and computed tomography (CT).

Materials and Methods

In a retrospective single-center study, patients with primary OSCC resection and systematic ND performed in 4 different manners (MRND III bilateral, MRND III left and SND right, MRND III right, SND left, and SND bilateral) were examined. Lymph node involvement allocated to levels was evaluated depending on primary localization and T-stage.

Results

A total of 177 consecutive patients (mean age 63.64; 92 female, male 85) were enrolled in this study. A total of 38.98% showed cervical lymph node involvement, and metastases were found in levels 1–4. The distribution of positive lymph node metastases (n=190 LNs) was 39.47% in level 1, 38.95% in level 2, 10.53% in level 3, and 11.05% in level 4.

Discussion

In a cohort of OSCC patients with systematic bilateral ND, levels 1 and 2 had positive lymph node involvement, and no lymph node involvement was seen at level 5. Without any clinical or imaging suspicion, ND expanding 5-level MRND should be avoided regardless of the primary tumor localization, T-stage and intraoperative proof of cervical metastases.

Selective Neck Dissection for Node-Positive Oral Cavity Squamous Cell Carcinoma: A Retrospective Cohort Study

Introduction  Selective neck dissection in clinically node-negative neck is considered the standard of care for oral squamous cell carcinomas (SCCs). Controversy still prevails in node-positive disease regarding the extent of neck dissection. In our part of the world, comprehensive neck dissection is mostly considered to be the minimal optimal treatment for palpable neck disease.

Objective  To compare regional control and disease-specific survival between clinically node-positive and node-negative patients undergoing selective neck dissection for oral SCC.

Methods  This was a retrospective cohort study conducted in the department of ENT, Head and Neck surgery at a tertiary care hospital. All patients with biopsy-proven oral and lip SCC, with or without nodal disease, who underwent selective neck dissection between April 2006 and July 2015 were included in the study.

Results  During the study period, 111 patients with oral SCC underwent selective neck dissection, of whom 71 (62%) were clinically node-negative and 40 (38%) patients had clinically positive nodes in the neck. The mean follow-up was 16.62 months (standard deviation [SD]: 17.03). The overall regional control rates were 95 versus 96% for clinical negative versus positive nodes, respectively ( p  = 0.589). The disease-specific survival was 84.5% in the node negative group versus 82.5% in the node-positive group ( p  = 0.703).

Conclusion  Selective neck dissection in node-positive neck oral SCC has similar regional control rates when compared with node-negative neck SCC. The difference in disease-specific survival between the two groups is also not significant.

Analysis of the Role of Selective Neck Dissection in Clinically Node-Positive T3/T4 Oral Cancers

Introduction

The concept of selective neck dissection (SND) in locally advanced oral cancers is emerging. Contemporary studies support the feasibility of SND in selected node-positive oral cancers with early primaries. Nevertheless, the suitability of SND in clinically node-positive (cN+) oral cancers with advanced primaries (T3/T4) is unknown.

Aim

This study explores if patients with cN+ advanced primaries were suitable candidates for SND by spotting the involved lymph node distribution in various stations of the neck. Secondary objectives were to check if predictive clinicopathological factors for metastases to the neck in general also apply for lymph node metastases to levels IV and V.

Methods

The present retrospective study analysed the distribution of pathologically involved lymph nodes in 134 patients and explored the interrelation of various predictive factors and cervical metastases overall and those specific to levels IV and V.

Results

Level V was involved in 6.7% (6/83) of T4 and none of the T3 primaries. Depth of invasion (DOI), perineural invasion (PNI), and skin invasion were statistically significant predictors for nodal metastases in general on multivariate analysis.

Conclusion

Our analysis supports the option of considering SND, sparing level V in patients with cN+ oral cancers in a subset with T3 primary and nodal stage N2 and below.

Prevalence of Metastasis and Involvement of Level IV and V in Oral Squamous Cell Carcinoma: A Systematic Review

The occurrence of occult metastases in oral cavity squamous cell carcinoma (OSCC) to lower levels in the neck (levels IV and V) or development of skip metastases that bypass the upper neck levels (levels I to III) and go directly to level IV or V is common. This challenges the efficacy of conventional neck dissection approaches in the treatment of OSCC. Therefore, the decision to include lower levels cervical nodes during elective neck dissection of OSCC remains controversial. This systematic review was designed to assess the prevalence of level IV and/or V involvement or skip metastases in patients with the clinically negative neck (cN0) or positive (cN+) oral squamous cell carcinoma (OSCC). We searched for studies published between December 2000 and December 2020. Potentially relevant abstracts and full-text articles were screened, and data from the studies were extracted. Quality was rated using the Newcastle Ottawa Scale (NOS) criteria. In total, 802 abstracts and 227 full-text articles were screened, and 32 studies were included in this analysis. The prevalence of metastasis ranged from 1.8% to 66.0%. The incidence for skip metastasis to level IV or V was low, reaching 8.5%. Evidence favored elective neck dissection, including levels I to III, in selected patients with OSCC and patients with cN0 or cN+ neck. The literature was non-conclusive on the recommendation for inclusion of lower levels.

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.

Automatic detection of cervical lymph nodes in patients with oral squamous cell carcinoma using a deep learning technique: a preliminary study

OBJECTIVE

To apply a deep learning object detection technique to CT images for detecting cervical lymph nodes metastasis in patients with oral cancers, and to clarify the detection performance.

METHODS

One hundred and fifty-nine metastatic and 517 non-metastatic lymph nodes on 365 CT images in 56 patients with oral squamous cell carcinoma were examined. The images were arbitrarily assigned to training, validation, and testing datasets. Using the neural network, 'DetectNet' for object detection, the training procedure was conducted for 1000 epochs. Testing image datasets were applied to the learning model, and the detection performance was calculated.

RESULTS

The learning curve indicated that the recall (sensitivity) for detecting metastatic and non-metastatic lymph nodes reached 90% and 80%, respectively, while the model performance recall by applying the test dataset was 73.0% and 52.5%, respectively. The recall for detecting level IB and Level II metastatic lymph nodes was relatively high.

CONCLUSIONS

A system that has the potential to automatically detect cervical lymph nodes was constructed.