Accessory Nerve Function in Lateral Selective Neck Dissection with Undissected Level IIB

A Study of the Prognostic Factors for Late Cervical Lymph Node Metastasis and Distant Metastasis in Patients with cT1-2N0 Tongue Cancer

Background: Early-stage tongue cancer has a good prognosis in general; however, high-risk patients with late cervical lymph node and distant metastases have a poor prognosis. Elective neck dissection and postoperative chemoradiotherapy are considered for these patients, although no clear criteria have been identified for their evaluation. Methods: This retrospective observational study aimed to determine the predictive factors for late cervical lymph node and distant metastases in 102 patients with cT1-2N0 tongue cancer. The data regarding the demographic characteristics, as well as the depth of invasion, tumor budding, histological grade, and tumor-stromal ratio, among other things, were extracted from medical records. Results: We found that the potential lymph node metastasis rate was 27.5%. The significant clinical predictors of late cervical lymph node metastasis were the tumor thickness and endophytic growth pattern and the significant histopathological factors were poorly and moderately differentiated tumors and ≥3 tumor buds. In addition, the prognostic factors for distant metastasis included ≥4 lymph node metastases, ≥7 tumor budding, and moderate and poor tumor differentiation. Conclusions: The usefulness of tumor budding as a predictor of metastasis for tongue cancer was suggested. The findings of this study can help establish the criteria for evaluating the metastasis risk and prognosis of patients with tongue cancers.

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.

Shoulder function after neck dissection with level IIb preservation: a prospective observational study

BACKGROUND

Shoulder syndrome can be reduced by preserving the spinal accessory nerve (SAN). However, it is unclear whether performing level IIb preservation will decrease the risk of SAN injury and shoulder syndrome.

AIMS/OBJECTIVES

We investigated whether neck dissection with level IIb preservation can reduce shoulder dysfunction and postoperative quality of life (QOL) in head and neck cancer patients.

MATERIAL AND METHODS

This prospective observational study enrolled patients who underwent neck dissection from 2011 to 2014. Patients were divided into three groups (level IIb preservation group [group 1], IIb dissection group [group 2], and IIb and V dissection group [group 3]). Postoperative shoulder function and QOL were evaluated among the three groups.

RESULTS

There were a total of 35 neck sides in three groups, with nine neck sides in group 1, 16 neck sides in group 2, and 10 neck sides in group 3. Although the results showed less shoulder dysfunction in group 1 at early postoperative period. The QOL in group 1 was preserved in the early postoperative period.

CONCLUSIONS AND SIGNIFICANCE

Neck dissection with level IIb preservation may help reduce shoulder syndrome and maintain QOL in the early postoperative period.

Lymph node metastasis in level IIb in oropharyngeal squamous cell carcinoma: a multicentric, longitudinal, retrospective analysis

INTRODUCTION

Nowadays, 70% of patients in Europe and the USA are affected by a p16 + , potentially HPV driven oropharyngeal squamous cell carcinoma. However, despite the improved survival rate in this group, the quality-of-life remains low in cases which neck dissection took place. In this vein, in recent years, some surgeons have considered to avoid dissection of level IIB, proposing a supra-selective non-IIb neck dissection.

MATERIALS AND METHODS

A retrospective, longitudinal, multicentric study was conducted, including patients with pathologically confirmed primary HPV + or HPV - OPSCC who went through surgical treatment for the primary lesion and neck dissection.

RESULTS

141 patients were included. Among them, 99 (70.2%) were male and 42 (29.8%) were female. The mean age was 62 ± 9 years (range 36-81). The most frequent anatomical location was the tonsil in 63 (44.7%) of patients. The most common approach was the classic transoral oropharyngectomy in 51 (36.2%) patients. Immunohistochemistry for p16 was positive in 62 (44%) patients. One-hundred and five (74.5%) patients received a unilateral ND, and a 36 (25.5%) a bilateral ND. Of those, a 12.8% (18/141) of patients were level IIb LN + . According to our results, level IIb ND should be considered in patients underwent therapeutic ND with positive LN metastasis in level IIa (OR = 9.83; 95% CI 3.463-27.917) or III (OR = 6.25; 95% CI 2.158-18.143), advanced (T3/T4) oropharyngeal primary tumors (OR = 3.38; 95% CI 1.366-8.405), and patients with ENE (OR = 6.56; 95% CI 2.182-19.770), regardless of p16 status.

CONCLUSIONS

According to our results, level IIb ND should be considered in patients who underwent therapeutic ND with positive LN metastasis in level IIa or III, advanced oropharyngeal primary tumors, and patients with ENE, independently of p16 status. Prospective data are necessary to definitively ensure the safety of omitting ipsilateral or contralateral level IIb ND in cN - patients with early stage disease.

2b or not 2b? Shoulder function after level 2b neck dissection: A double-blind randomized controlled clinical trial

BACKGROUND

Selective neck dissection (SND) is a mainstay of head and neck cancer treatment. A common sequela is shoulder syndrome from spinal accessory nerve (SAN) trauma. Extensive dissection in neck levels 2 and 5 leads to SAN dysfunction. However, it is not known whether limited level 2 dissection reduces SAN injury. The purpose of this double-blind randomized controlled trial was to determine whether omitting level 2b dissection would improve shoulder-related quality of life and function.

METHODS

Patients with head and neck cancers undergoing surgery were randomized 1:1 to SND without level 2b dissection (group 1) or with it (group 2) on their dominant-hand side. Patients, caregivers, and assessors were blinded. The primary outcome was the change in the Neck Dissection Impairment Index (NDII) score after 6 months. An a priori calculation of the minimally important clinical difference in the NDII score was determined to establish a sample size of 15 patients per group (power = 0.8). Secondary outcomes included shoulder strength and range of motion (ROM) and SAN nerve conduction. The trial was registered at ClinicalTrials.gov (NCT00765791).

RESULTS

Forty patients were enrolled, and 30 were included (15 per group). Six months after the surgery, group 2 demonstrated a significant median decrease in the NDII from the baseline (30 points) and in comparison with group 1, whose NDII dropped 17.5 points (P = .02). Shoulder ROM and SAN conduction demonstrated significant declines in group 2 (P ≤ .05). No adverse events occurred.

CONCLUSIONS

Level 2b should be omitted in SND when this is oncologically safe and feasible. This allows for an optimal balance between function and cancer cure.

The necessity of IIb dissection in T1-T2N0M0 oral squamous cell carcinoma: protocol for a randomized controlled trial

Background

There is a growing debate on the relationship between health-related quality of life (HRQoL) and patient survival which has been going on for the last few decades. The greatest wish of clinicians is to extend the latter while improving the former. Following neck dissection of early-stage oral carcinoma, “shoulder syndrome” appears due to traction of the accessory nerve during removal of level IIb, which greatly affects patient quality of life. Since occult metastasis in level IIb of early-stage oral carcinoma is extremely low, some surgeons suggest that level IIb can be exempt from dissection to improve the HRQoL. However, other surgeons take the opposite view, and thus there is no consensus on the necessity of IIb dissection in T1–2N0M0 oral squamous cell carcinoma (OSCC).

Methods

We designed a parallel-group, randomized, non-inferiority trial that is supported by Shanghai Ninth People’s Hospital, Shanghai Jiao Tong University, School of Medicine, Shanghai, China. We will enroll 522 patients with early oral carcinoma who match the inclusion criteria, and compare differences in 3-year overall survival, progression–free survival (PFS) and HRQoL under different interventions (retention or dissection of level IIb). The primary endpoints will be tested by means of two-sided log-rank tests. Analysis of overall and progression-free survival will be performed in subgroups that were defined according to stratification factors with the use of univariate Cox analysis. In addition, we will use post-hoc subgroup analyses on the basis of histological factors that were known to have effects on survival, such as death of invasion of the primary tumor. To evaluate HRQoL, we will choose the Constant–Murley scale to measure shoulder function.

Discussion

Currently, there are no randomized controlled trials with large sample sizes on the necessity of IIB dissection in T1–T2N0M0 OSCC. We designed this noninferiority RCT that combines survival rate and HRQoL to assess the feasibility of IIb neck dissection. The result of this trial may guide clinical practice and change the criteria of how early-stage oral cancer is managed. The balance between survival and HRQoL in this trial is based on early-stage breast cancer treatment and may provide new ideas for other malignancies.

Trial registration

Chinese Clinical Trial Registry, ChiCTR1800019128. Registered on 26 October 2018.

Electronic supplementary material

The online version of this article (10.1186/s13063-019-3683-y) contains supplementary material, which is available to authorized users.

Shoulder Function in Various Types of Neck Dissection. Role of Spinal Accessory Nerve and Cervical Plexus Preservation

Aims and background

The aim of this study is to determine the effects of two different types of nerve-sparing neck dissection on shoulder function. Even if the spinal accessory nerve is spared in functional neck dissection, some degree of shoulder syndrome may occur. The role of the cervical plexus in shoulder function and the effects of dissection of level 5 are emphasized.

Methods

Twenty-six patients with laryngeal carcinoma were studied prospectively. Seventeen anterolateral and 15 functional neck dissections were performed. Electromyographic evaluation was carried out in all patients to assess spinal accessory nerve function preoperatively and at the sixth week and sixth month postoperatively. Shoulder disability was evaluated by a questionnaire (shoulder pain disability index) and goniometric measurements were done preoperatively and at the sixth postoperative month.

Results

In patients who underwent anterolateral neck dissection, the goniometric results were better than in the functional neck dissection group. The questionnaire results also showed better quality of life of patients who underwent anterolateral neck dissection. Electrophysiological evaluation of the trapezius muscles of both groups at the sixth week showed significant differences. The distal motor latency values of the anterolateral neck dissection group were shorter than those of the other group. Electrophysiological evaluation at the sixth postoperative month showed shorter distal latency values in the anterolateral dissection group, without statistical significance.

Conclusions

Preservation of the cervical plexus and less disturbance of the spinal accessory nerve are important to diminish postoperative shoulder disability. The type of neck dissection has an important influence on shoulder function.

Level IIb Neck Dissection in Oral Cavity Cancers- When Should One Address it..?

Nodal metastases is the most important prognostic marker for oral cavity cancers. Nodal dissection at level IIb risks damage to the spinal accessory nerve. We aim to study positivity of level IIb lymph nodes in oral cancers. In this non-randomized prospective observational study, 65 patients of oral cavity cancers were evaluated. Appropriate surgery for primary tumour and neck dissection were undertaken. All patients underwent level II b dissection. Out of 67 neck dissections (27 elective and 40 therapeutic), 7 patients had level IIb positive for metastases (10.44 %) with no isolated or contralateral metastases at level IIb and direct correlation with level IIa nodes. There was no statistical association of level IIb positivity with stage or site of primary. Level IIb dissection can be avoided in N0 necks. For therapeutic neck dissections, Level IIb should be cleared if there are positive nodes at level IIa.

Involvement of level IIb lymph node metastasis and dissection in thyroid cancer

Thyroid neoplasms are the most frequent neoplasm in the head and neck region. Most thyroid carcinomas are well-differentiated tumors of follicular cell origin. Thyroid papillary carcinoma (TPC) is the most common thyroid malignancy. It constitutes 60% to 90% of all the thyroid carcinomas and cervical lymph node metastases are commonly seen in these patients. Although cervical lymph node metastases are common in this cancer, the management and the prognostic role of lymph nodes in TPC remains controversial. In this paper we reviewed the currently available literature regarding the extent of lateral neck dissection in papillary thyroid carcinoma patients with lateral neck metastasis.

Measurement of the trapezius muscle volume: A new assessment strategy of shoulder dysfunction after neck dissection for the treatment of head and neck cancers

BACKGROUND

The purpose of this study was to determine the actual degree of shoulder muscle change and its relation to symptoms after neck dissection for head and neck cancers.

METHODS

Forty-two patients who underwent unilateral neck dissection were selected. Data obtained from each subject were trapezius muscle volume ratio and a Shoulder Disability Questionnaire (SDQ) score. Patients who had undergone neck dissection with spinal accessory nerve (SAN) preservation were compared with those who had received radical neck dissection. The preservation group was further separated into subgroups by the extent of neck dissection.

RESULTS

Trapezius muscle volume ratio was higher and SDQ score was significantly lower in the SAN preservation group compared to the radical neck dissection group. However, the SAN preservation subgroups did not differ from each other. In addition, a good correlation between the muscle volume ratio and SDQ score was observed.

CONCLUSION

With trapezius muscle volume ratio, clinicians may be able to diagnose shoulder dysfunction after neck dissection. Further research on the subject is warranted. This suggests a novel strategy for assessing the degree of shoulder dysfunction.

Head and neck cutaneous squamous cell carcinoma metastatic to cervical sublevel IIb lymph nodes occurred from primary sites involving the auricle and adjacent neck

PURPOSE

Neck dissections that include sublevel IIb increase the risk of postoperative shoulder dysfunction. The purpose of this investigation was to document the incidence of level IIb metastatic lymphatic spread in a group of patients undergoing neck dissection as part of the surgical management of cutaneous squamous cell carcinoma of the head and neck.

MATERIALS AND METHODS

A retrospective review of the pathology records taken from 1 surgeon from June 2006 through June 2013 was carried out. The predictor variable was the primary tumor site. The outcome variable was the metastatic nodal involvement according to neck level and sublevel. Secondary variables included T stage, pathologist, tumor depth, and the presence of perineural, perilymphatic, and perivascular invasion. Data analyses were by descriptive statistics.

RESULTS

Thirty-six patients with a total of 40 neck dissections met the inclusion criteria. The average primary site tumor depth was 14.7 mm, and there were 16 cases of poorly differentiated squamous cell carcinoma. Sublevel IIb was involved in 7.5% of cases, all of which occurred from lateralized primary sites of the head and neck.

CONCLUSIONS

Cutaneous squamous cell carcinoma arising from the auricle and neck sites adjacent to sublevel IIb may have increased risk of metastatic involvement of sublevel IIb nodes. Further studies with larger numbers are required to determine the risk of metastasis to sublevel IIb from midline sites of the face.

Evaluating the significance of level IIb neck dissection for hypopharyngeal cancer

BACKGROUND

This study evaluated cervical lymph node metastases at level IIb in cases of hypopharyngeal cancer and analyzed the possibility of preservation of level IIb during neck dissection.

METHODS

In total, 34 patients (51 neck sides) with hypopharyngeal cancer that underwent neck dissection from April 2008 to April 2011 were retrospectively analyzed. We evaluated the distribution of metastatic lymph nodes at various levels (particularly level IIb) in cases treated with therapeutic neck dissection and elective neck dissection.

RESULTS

The incidence of metastases in level IIb was 13.3% (4 of 30 patients) for therapeutic neck dissection and 0% (0 of 21 patients) for elective neck dissection. All the level IIb metastases were found on the ipsilateral side in the cases treated with therapeutic neck dissection.

CONCLUSIONS

The results suggest that preservation of level IIb during neck dissection was possible in N0 cases of hypopharyngeal cancer.

A double blind randomised trial of IIb or not IIb neck dissections on electromyography, clinical examination, and questionnaire-based outcomes: a feasibility study

The aim of this double-blind randomised controlled trial was to evaluate the feasibility of a study to compare differences using electromyographic (EMG) or nerve conduction studies (NCS), questionnaires completed by patients, and range of movement, after selective supraomohyoid neck dissection in patients with and without level IIb for node-negative oral cancer. Between January 2006 and July 2008 we recruited 57 previously untreated consecutive patients with node-negative T1 or T2 squamous cell carcinomas (SCC) of the anterior two-thirds of the tongue and floor of the mouth. Thirty-eight patients were randomised (32 unilateral and 6 bilateral dissections) into two groups. Preoperatively and at 6 weeks postoperatively we collected EMG or NCS data on trapezius muscle activity (primary outcome), the University of Washington quality of life scale (UWQoLv4), the neck dissection impairment index (NDII), and range of movement. At 6 months data on range of movement and data from the questionnaires were obtained. There was a greater mean fall in trapezius M-response amplitude for those who had IIb dissected, which suggested that inclusion of this level caused additional morbidity. However, it was not significant for patients who had unilateral dissections or for all necks combined. Changes in M-amplitude from baseline to 6 weeks, and from baseline to 6 months were strongly associated with changes in the shoulder domain of the UWQoL and the NDII, but were less strong for change in range of movement. This feasibility study has shown that a randomised controlled trial (RCT) is achievable. The combination of EMG or NCS with questionnaire data preoperatively and to 6 weeks would suffice and would simplify a new study design.

Pattern of lymph node metastases in squamous cell carcinoma of the tonsil: implication for selective neck dissection

The aim of this study was to prospectively analyze the distribution of neck metastases and the outcome in patients surgically treated for tonsillar carcinoma in order to deduce implications for selective neck dissection. The criteria for inclusion in the study were (1) previously untreated, histologically proven, resectable squamous cell carcinoma of the tonsil, (2) curative surgical intent on the primary tumor and neck, (3) no history of prior head and neck cancer, (4) absence of synchronous second primary in the upper aerodigestive tract, lung and esophagus, (5) absence of distant metastases. Fifty-eight previously untreated consecutive patients with tonsillar squamous cell carcinoma were included in this prospective study. Among 22 patients with clinically negative cervical lymph nodes, 4 patients (18.2%) had metastatic lymph nodes on pathologic examination. Occult node metastases were mainly located in ipsilateral II level. No occult metastases occurred at levels I and V. Among 36 patients with clinically positive cervical lymph nodes, 3 patients (8.3%) had an occult pathologic metastatic involvement of cervical lymph nodes of ipsilateral level V. Level I was free of lymph node metastases. Clinical N category >N2a (p=0.003), nodal metastases to levels III (p=0.026) and IV (p=0.009) were significantly related to level V nodal metastases. The 2 and 5 years actuarial disease-free survival was 82.7% (95% CI 71.2-93.5%) and 58.3% (95% CI 36.7-79.9%), respectively. The actuarial recurrence-free survival was 87.9% (95% CI 78.9-96.8%) and 72.2% (95% CI 53.9-90.5%) at 2 and 5 years, respectively. Our findings support the role of a selective lateral neck dissection in the management of clinically N0 necks and in selected N+ necks (N1 and N2a disease located at level II) in patients with tonsillar carcinoma without oral involvement.

Elective supraomohyoid neck dissection for oral cavity squamous cell carcinoma: Is dissection of sublevel IIB necessary?

Spinal accessory nerve (SAN) dysfunction and related shoulder disability are common consequences of supraomohyoid neck dissection (SOHND). Nerve dysfunction is usually attributed to excessive nerve traction or devascularization during clearance of the lymph nodes posterior and superior to the SAN (sublevel IIB). The need for routine dissection of this sublevel with elective neck dissection has recently been questioned. This review article discusses whether preserving sublevel IIB lymph nodes is justified in elective SOHND for patients with squamous cell carcinoma (SCC) of the oral cavity. A review of the literature was conducted on studies of sublevel IIB dissection in elective SOHND for SCC of the oral cavity. Only two studies have prospectively investigated the incidence of lymph node metastasis in patients with clinically N0 SCC of the oral cavity. Data from these two prospective pathologic and molecular analyses of neck dissection specimens, including 122 patients with N0 oral cancer, revealed 7.3% with positive neck nodes at sublevel IIB for oral cancer in general, and 12% for tongue cancer in particular. When considering the merits of preservation of sublevel IIB, the benefit of preservation of SAN function has to be weighed against potentially reduced oncologic control.

Spinal accessory nerve palsy: associated signs and symptoms

STUDY DESIGN

Retrospective case series.

BACKGROUND

Spinal accessory nerve palsy (SANP) is common following neck dissection surgery and can occur with blunt or penetrating trauma to the lateral neck region and cervical stretch injuries. Early detection of SANP remains a clinical challenge and the condition is often misdiagnosed. The purpose of this case series is to describe the associated history, signs, and symptoms related to SANP and increase awareness of the scapular flip sign as a clinical sign associated with SANP. CASE SERIES DESCRIPTION: Twenty subjects (13 male, 7 female) presented with pain and decreased shoulder function following head and neck surgery or posttrauma. All patients were thoroughly examined and the scapular flip sign was assessed. All patients presented with a cluster of signs and symptoms including trapezius atrophy, shoulder girdle depression, limited active shoulder abduction to less than 90 degrees , shoulder pain, and shoulder weakness. A positive scapular flip sign was present in all cases. The middle and lower trapezius were rated as 0/5, based on manual muscle testing, indicating no identifiable muscle activation against resistance.

DISCUSSION

A typical history and consistent signs and symptoms were found related to SANP. A strong relationship appeared between the presence of the scapular flip sign and SANP. The suspected mechanism for the scapular flip sign is the unopposed pull of the humeral external rotators by the inactive middle and lower trapezius. Early identification of SANP can assist with the prognosis, explain persistent impairments and functional deficits, motivate appropriate diagnostic testing and interventions, and help maximize outcome. Further research to validate the scapular flip sign and establish a clinical prediction rule for the diagnosis of SANP should be performed.

Dissection of the submuscular recess (sublevel IIb) in squamous cell cancer of the upper aerodigestive tract: Prospective study and systematic review of the literature

BACKGROUND

Selective neck dissection is commonly used to clear occult neck metastases in the N0 neck. The aim of this study was to identify the incidence of occult metastases in lymph nodes of sublevel IIb (submuscular recess; SMR) in upper aerodigestive tract squamous cell carcinoma in the setting of clinically and radiologically staged N0 necks and to perform a systematic review of the literature on the incidence of metastases in this setting.

METHODS

We conducted a prospective study of 50 neck dissections and systematic review of the literature.

RESULTS

(A) Prospective study: Tissue dissected out from the SMR was sent separately for histopathologic analysis. Between 0 and 7 nodes were harvested from sublevel IIb. One patient had a metastatic node in sublevel IIb with extracapsular spread in the ipsilateral neck. No other positive nodes were detected. Sixteen necks showed occult metastases at other levels. (B) Systematic review: The review identified 14 articles with 903 necks suitable for inclusion. The overall incidence of metastatic disease at this sublevel in the context of an N0 neck from any site is 2.0% (18 of 903). The incidence of occult metastatic disease in sublevel IIb for oral cavity, oropharyngeal, and laryngeal cancer is 3.9% (11 of 279), 5.2% (5 of 96), and 0.4% (1 of 230) patients, respectively. Contralateral positive nodes (0.9%) and isolated metastases (0.3%) at this sublevel were rare.

CONCLUSION

Nodal metastases are uncommon in the SMR even in the presence of positive nodes in adjacent sublevel IIa. There appears to be no advantage in performing contralateral SMR dissection in N0 necks and in laryngeal primaries.

The spinal accessory nerve in head and neck surgery

PURPOSE OF REVIEW

To describe landmarks and tips used for minimizing surgical traumas to the spinal accessory nerve, and different options in case of its injury.

RECENT FINDINGS

Modified radical and selective neck dissections reduce the prevalence of shoulder syndrome, a sequela of radical neck dissection. Impaired shoulder mobility and pain may be present even after nerve-sparing procedures, as shown using electromyography, particularly when dissection is extended to level V. In these cases physical therapy is mandatory to prevent shoulder pain and functional limitations. The issue of spinal accessory nerve repair when macroscopically damaged or transected remains critical.

SUMMARY

Subclinical spinal accessory nerve impairment can be observed even after selective neck dissections (levels II-IV) due to routine clearance of sublevel IIB. Further studies should be performed to select patients in whom this sublevel could be left undissected without impairing oncologic radicality and to demonstrate if such a policy leads to better functional results. Early diagnosis of shoulder syndrome by questionnaires and clinical tests is recommended to appropriately plan physical therapy. Spinal accessory nerve repair is advocated to reduce the prevalence of shoulder syndrome after radical neck dissection. More data are needed to assess the superiority of newer techniques such as nerve transposition or bioresorbable nerve guides.

Preliminary multi-institutional prospective pathologic and molecular studies support preservation of sublevel IIB and level IV for laryngeal squamous carcinoma with clinically negative neck

Level II-IV selective neck dissection, often performed bilaterally, has become the procedure of choice for elective dissection of the clinically negative (N0) neck in the treatment of laryngeal cancer. The most significant morbidity of this procedure is dysfunction of the accessory nerve, incurred by the necessity of mobilization and retraction of the nerve in order to remove the contents of sublevel IIB. Other morbidity includes possible injury to the phrenic nerve and chylous fistula. These complications are associated with the dissection of level IV. A number of prospective multi-institutional studies of the distribution of cervical lymph node metastases in the neck indicate that lymph nodes in sublevel IIB and level IV are rarely involved in cases of laryngeal cancer with N0 neck. Information was obtained by the study of neck dissection specimens by conventional light microscopy, and by molecular analysis of the specimens. Molecular analysis reveals a significant number of metastases that are not discovered by light microscopy, and is thus essential for this type of evaluation. The authors conclude that these preliminary studies indicate that it is safe and appropriate to eliminate dissection of sublevel IIB and level IV from the elective neck dissection performed for laryngeal cancer with N0 neck. This practice will reduce both operating time and morbidity, particularly accessory nerve dysfunction, without compromising the oncologic result. Further prospective studies are needed to confirm these conclusions.