Level IIB lymph node metastasis in laryngeal and hypopharyngeal squamous cell carcinoma: Single-institution case series and review of the literature

Anatomic Variability of the Accessory Nerve: Implications for Dissection of Level IIB

OBJECTIVES

During neck dissection, level IIB lymphadenectomy necessitates manipulation of the spinal accessory nerve that might be avoided and might cause postoperative disability. Current literature does not describe the effect of variation in the spinal accessory nerve in the upper neck. We sought to measure the effect of the dimensions of level IIB on nodal yield in level IIB and on patient reported neck symptoms.

METHODS

We measured the boundaries of level IIB of 150 patients undergoing neck dissection. Level II was dissected and separated into levels IIA and IIB intraoperatively. Patient-reported symptoms were assessed in 50 patients using the Neck Dissection Impairment Inventory. We computed descriptive statistics, and sought to identify correlation with the number and proportion of level IIB nodes and the number of metastatic nodes. Level IIB dimensions were analyzed as predictors of postoperative symptoms.

RESULTS

We measured 184 sides, with 37.7% of level II nodes found in level IIB. Mean accessory nerve length across level II was 2.5 cm. Every additional 1 cm in accessory nerve length was associated with two more level IIB nodes. At all accessory nerve lengths, meaningful numbers of nodes were present in level IIB. Accessory nerve length and other factors did not correlate with NDII scores.

CONCLUSIONS

Longer lengths of accessory nerve across level IIB correlated with greater nodal yield. However, data did not point to an accessory nerve length cutoff below which level IIB dissection could be avoided. In addition, the dimensions of level IIB did not correlate with postoperative neck symptoms.

LEVEL OF EVIDENCE

2 Laryngoscope, 134:154-159, 2024.

Delineation of neck node levels for patients with locally advanced supraglottic cancer receiving radical intensity-modulated radiotherapy: a cross-sectional study in Mainland China

Background: To survey the diversity of clinical target volumes (CTVs) for locally advanced supraglottic cancer (LA-SGC) with radical radiotherapy in mainland China. Methods: Radiation oncologists from 30 provinces and four representative cases (T2N1, T3N2b, T4N0, T4N2c) were included. Results: High risk (HR)-CTV included involved and the lower adjacent level was followed by most physicians (n = 160, 97.6%). In the N0-1 stage, whether contralateral levels II-III should be included in HR- or low risk (LR)-CTV was controversial. In the N2 stage, the bilateral levels II-IVb were included in LR-CTV (75-92.5% agreement). Levels Ib, V or VIb were included in CTV requiring certain conditions. Conclusion: Involved and lower adjacent levels were as HR-CTV. Whether bilateral levels II-IV are included in HR- or LR-CTV remain controversial.

Total Laryngectomy: A Review of Surgical Techniques

Since the first total laryngectomy was performed in the late 18th century, several improvements and variations in surgical techniques have been proposed for this procedure. The surgical techniques employed in total laryngectomy have not been comprehensively discussed to date. Thus, the main objective of this article was to address controversial aspects related to this procedure and compare different surgical techniques used for a total laryngectomy procedure from the beginning to the end.

Although the management paradigms in laryngeal and hypopharyngeal squamous cell carcinomas have shifted to organ-preserving chemoradiotherapy protocols, total laryngectomy still plays a prominent role in the treatment of advanced and recurrent tumors. The increased incidence of complications associated with salvage total laryngectomy has driven efforts to improve the surgical techniques in various aspects of the operation. Loss of voice and impaired swallowing are the most difficult challenges to be overcome in laryngectomies, and the introduction of tracheoesophageal voice prostheses has made an enormous difference in postoperative rehabilitation and quality of life. Advancements in reconstruction techniques, tumor control, and metastatic management, such as prophylactic neck treatments and paratracheal nodal dissection (PTND), as well as the use of thyroid gland-preserving total laryngectomy in selected patients have all led to the increasing success of modern total laryngectomy. Several conclusions regarding the benchmarking of surgical techniques cannot be drawn. Issues regarding total laryngectomy are still open for discussion, and the technique will continue to require improvement in the near future.

Rational surgical neck management in total laryngectomy for advanced stage laryngeal squamous cell carcinomas

PURPOSE

Controversies exist in regard to surgical neck management in total laryngectomies (TL). International guidelines do not sufficiently discriminate neck sides and sublevels, or minimal neck-dissection nodal yield (NY).

METHODS

Thirty-seven consecutive primary TL cases from 2009 to 2019 were retrospectively analyzed in terms of local tumor growth using a previously established imaging scheme, metastatic neck involvement, and NY impact on survival.

RESULTS

There was no case of level IIB involvement on any side. For type A and B tumor midline involvement, no positive contralateral lymph nodes were found. Craniocaudal tumor extension correlated with contralateral neck involvement (OR: 1.098, p = 0.0493) and showed increased involvement when extending 33 mm (p = 0.0134). Using a bilateral NY of ≥ 24 for 5-year overall survival (OS) and ≥ 26 for 5-year disease-free survival (DFS) gave significantly increased rate advantages of 64 and 56%, respectively (both p < 0.0001).

CONCLUSIONS

This work sheds light on regional metastatic distribution pattern and its influence on TL cases. An NY of n ≥ 26 can be considered a desirable benchmark for bilateral selective neck dissections as it leads to improved OS and DFS. Therefore, an omission of distinct neck levels cannot be promoted at this time.

Incidence of Occult Lymph Node Metastasis in Primary Larynx Squamous Cell Carcinoma, by Subsite, T Classification and Neck Level: A Systematic Review

Background: Larynx cancer is a common site for tumors of the upper aerodigestive tract. In cases with a clinically negative neck, the indications for an elective neck treatment are still debated. The objective is to define the prevalence of occult metastasis based on the subsite of the primary tumor, T classification and neck node levels involved. Methods: All studies included provided the rate of occult metastases in cN0 larynx squamous cell carcinoma patients. The main outcome was the incidence of occult metastasis. The pooled incidence was calculated with random effects analysis. Results: 36 studies with 3803 patients fulfilled the criteria. The incidence of lymph node metastases for supraglottic and glottic tumors was 19.9% (95% CI 16.4–23.4) and 8.0% (95% CI 2.7–13.3), respectively. The incidence of occult metastasis for level I, level IV and level V was 2.4% (95% CI 0–6.1%), 2.0% (95% CI 0.9–3.1) and 0.4% (95% CI 0–1.0%), respectively. For all tumors, the incidence for sublevel IIB was 0.5% (95% CI 0–1.3). Conclusions: The incidence of occult lymph node metastasis is higher in supraglottic and T3–4 tumors. Level I and V and sublevel IIB should not be routinely included in the elective neck treatment of cN0 laryngeal cancer and, in addition, level IV should not be routinely included in cases of supraglottic tumors.

MicroRNA-153 suppresses human laryngeal squamous cell carcinoma migration and invasion by targeting the SNAI1 gene

Human laryngeal squamous cell carcinoma (LSCC) is a malignant cancer type. Epithelial-mesenchymal transition marker Snail family transcriptional repressor 1 (SNAI1) is associated with the occurrence, development, invasion and metastasis of numerous tumor types, such as lung, liver and ovarian cancer. Previous studies have indicated that microRNA-153 (miR-153) may serve as a novel tumor suppressor, which is involved in tumor metastasis; however, the role and clinical significance of miR-153 in LSCC are not fully understood. The aim of the present study was to determine the role of miR-153 in the growth and aggressiveness of LSCC cells. Bioinformatics prediction method, western blot analysis, Matrigel invasion assay and immunofluorescence were used to analyze whether SNAI1 can be regulated and controlled by miR-153 in LSCC cells. An inverse association between miR-153 and SNAI1 was observed in LSCC tissues. It was demonstrated that SNAI1 is a direct target of miR-153 in LSCC. In addition, the results indicated that miR-153 knockdown inhibited PCI-13 cell migration and invasion by targeting SNAI1, which may be a potential marker that can reflect the degree of malignancy in patients with LSCC. Furthermore, miR-153 knockdown decreased Twist family BHLH transcription factor 1 and metastasis-associated 1 family member 3 expression in LSCC cells. In conclusion, these data indicated that miR-153 regulates LSCC migration via the targeting of SNAI1 gene, which may be a potential predictor for patients with LSCC.

Selective neck irradiation for supraglottic cancer: focus on Sublevel IIb omission

OBJECTIVE

To estimate selective neck irradiation omitting surgical Sublevel IIb.

METHODS

Bilateral necks of 47 patients (94 necks) were subjected to definitive radiotherapy for supraglottic cancer. Sixty-nine and 25 necks were clinically node negative (cN-) and clinically node positive (cN+), respectively. We subdivided Sublevel IIb by the international consensus guideline for radiotherapy into Sublevel IIb/a, directly posterior to the internal jugular vein, and Sublevel IIb/b, which was behind Sublevel IIb/a and coincided with surgical Sublevel IIb. Bilateral (Sub)levels IIa, III, IV and IIb/a were routinely irradiated, whereas Sublevel IIb/b was omitted from the elective clinical target volume in 73/94 treated necks (78%).

RESULTS

Two patients presented with ipsilateral Sublevel IIb/a metastases. No Sublevel IIb/b metastasis was observed. Five patients experienced cervical lymph node recurrence; Sublevel IIb/a recurrence developed in two patients, whereas no Sublevel IIb/b recurrence occurred even in the cN- necks of cN+ patients or cN0 patients. The 5-year regional control rates were 91.5% for Sublevel IIb/b-omitted patients and 77.8% for Sublevel IIb/b treated patients.

CONCLUSIONS

Selective neck irradiation omitting Sublevel IIb/b did not compromise regional control and could be indicated for cN- neck of supraglottic cancer.

Current philosophy in the surgical management of neck metastases for head and neck squamous cell carcinoma

Neck dissection is an important treatment for metastases from upper aerodigestive carcinoma; an event that markedly reduces survival. Since its inception, the philosophy of the procedure has undergone significant change from one of radicalism to the current conservative approach. Furthermore, nonsurgical modalities have been introduced, and, in many situations, have supplanted neck surgery. The refinements of imaging the neck based on the concept of neck level involvement has encouraged new philosophies to evolve that seem to benefit patient outcomes particularly as this relates to diminished morbidity. The purpose of this review was to highlight the new paradigms for surgical removal of neck metastases using an evidence-based approach.