Sentinel node identification in laryngeal and pharyngeal carcinoma after flexible endoscopy-guided tracer injection under topical anesthesia: A feasibility study

BACKGROUND

The aim of this study was to investigate the feasibility of flexible endoscopy-guided tracer injection for sentinel lymph node (SLN) identification in patients with laryngeal and pharyngeal carcinoma.

METHODS

Sixteen cT1-4N0-2M0 patients with laryngeal or pharyngeal carcinoma underwent intra- and peritumoral [^99m Tc]Tc-nanocolloid injections after topical anesthesia under endoscopic guidance. SPECT-CT scans were performed at two time points.

RESULTS

Tracer injection and visualization of SLNs was successful in 15/16 (94%) patients. Median number of tracer injections was 1 intratumoral and 3 peritumoral. The median duration of the endoscopic procedure including tracer injection after biopsy taking was 7 min (range 4-16 min). A total of 28 SLNs were identified which were all visualized on the early and late SPECT-CT. Most SLNs were visualized in neck levels II and III.

CONCLUSIONS

Flexible endoscopy-guided tracer injection for SLN identification is a feasible and fast procedure in laryngeal and pharyngeal carcinoma patients.

Diagnostic test accuracy of sentinel lymph node biopsy in squamous cell carcinoma of the oropharynx, larynx, and hypopharynx: A systematic review and meta-analysis

The aim of this meta-analysis was to determine the diagnostic test accuracy of sentinel lymph node biopsy (SLNB) in patients with oropharyngeal, laryngeal, and hypopharyngeal squamous cell carcinoma (SCC). For this purpose, MEDLINE, EMBASE, and Web of Science were searched from inception to March 8, 2022. Included were studies evaluating diagnostic test accuracy of SLNB to identify cervical lymph node metastases with elective neck dissection or follow-up as reference. A bivariate generalized linear mixed model approach was used for the meta-analysis. Nineteen studies were eligible, evaluating 377 cases in total. The pooled estimates of sensitivity and negative predictive value were 0.93 (95% CI: 0.86-0.96) and 0.97 (95% CI: 0.94-0.98), respectively. The excellent accuracy of SLNB justifies a place in the diagnostic workup of patients with larynx and pharynx SCC. Randomized trials are required to demonstrate oncologic safety and benefits on treatment related morbidity and quality of life when omitting elective neck treatment based on SLNB.

Novel Diagnostic Approaches for Assessment of the Clinically Negative Neck in Head and Neck Cancer Patients

In head and neck cancer, the presence of nodal disease is a strong determinant of prognosis and treatment. Despite the use of modern multimodality diagnostic imaging, the prevalence of occult nodal metastases is relatively high. This is why in clinically node negative head and neck cancer the lymphatics are treated “electively” to eradicate subclinical tumor deposits. As a consequence, many true node negative patients undergo surgery or irradiation of the neck and suffer from the associated and unnecessary early and long-term morbidity. Safely tailoring head and neck cancer treatment to individual patients requires a more accurate pre-treatment assessment of nodal status. In this review, we discuss the potential of several innovative diagnostic approaches to guide customized management of the clinically negative neck in head and neck cancer patients.

Lymphoscintigraphy for Sentinel Node Mapping in Head and Neck Cancer

The aim of this comprehensive review is to describe and analyze the role of the sentinel node mapping in head and neck cancers. For this purpose, head and neck neoplasms have been categorized in cutaneous malignancies and neoplasms of the upper aerodigestive tract. A concise description of lymphatic drainage will be the "prelude" for each section, as well as the description of the injection techniques, when specific. Concisely, the attention has been focused on detection rate of the sentinel node by lymphoscintigraphy for each cancer, and for those patients in which the sentinel lymph node has been identified, true-positives rates, false-negative rates, and overall accuracy has been pointed out. Overall, in cutaneous neoplasms of the head and neck, the detection rate is higher than 90%, however the false-negative rate is still an issue, in particular in melanoma, inducing the need for newer developments. In fact, new tracers and techniques are already available, while prospective multicenter trials exploring the outcome impact are needed in the near future. For the upper aerodigestive tract and in particular oral cavity and oropharynx, sentinel lymph node identification by lymphoscintigraphy allows avoiding unnecessary neck dissection and/or node irradiation. Even in this case, the main limit remains the risk of false-negative rates. While, for patients affected by laryngeal and hypopharyngeal cancers the data seem very limited and, although the feasibility has been demonstrated, performances of this lymphoscintigraphy still need to be confirmed by multicenter studies.

Factors contributing to lymph node occult metastasis in supraglottic laryngeal carcinoma cT2-T4 N0M0 and metastasis predictive equation

OBJECTIVE

To investigate factors that contribute to lymph node metastasis (LNM) from clinical cT2-T4 N0M0 (cN0) supraglottic laryngeal carcinoma (SLC), and to predict the risk of occult metastasis before surgery.

METHODS

A total of 121 patients who received surgery were retrospectively analyzed. Relevant factors regarding cervical LNM were analyzed. Multivariate analyses were conducted to predict the region where the metastasis occurred and prognosis.

RESULTS

The overall metastatic rate of cN0 SLC was 28.1%. Metastatic rates were 15.4%, 32.5% and 35.7% for T2, T3 and T4, respectively. Metastatic rates for SLC levels II, III and IV were 19.6%, 17.2% and 3.6%, respectively. A regression equation was formulated to predict the probability of metastasis in cN0 SLC as follows: Pn=e((-3.874+0.749T3+1.154T4+1.935P1+1.750P2))/[1+e((-3.874+0.749T3+1.154T4+1.935P1+1.750P2))]. Approximately 0.2% of patients experienced LNM with no recurrence of laryngeal cancer. Comparison of the intergroup survival curves between patients with and without LNM indicated a statistically significant difference (P=0.029).

CONCLUSIONS

Cervical lymph node metastatic rates tended to increase in tandem with T stage in patients with LNM in cN0 SLC, and neck dissection is advised for these patients. Moreover, cervical LNM in cN0 SLC showed a sequential pattern and may be predicted.

Management of cervical lymph nodes for cN0 advanced glottic laryngeal carcinoma and its long-term results

CONCLUSIONS

Cervical lymph node metastatic rates tend to increase by T stage in cN0 glottic laryngeal carcinoma (GLC). Moreover, cervical lymph node metastasis (LNM) shows a sequential pattern according to the regions involved and LNM affects the prognosis.

OBJECTIVES

To investigate factors that contribute to LNM of N0 (cN0) T2-T4 GLC and their effect on prognosis.

METHODS

A total of 212 GLC patients who had been admitted between December 2002 and January 2013 were retrospectively analyzed. They included 202 men and 10 women, median age 58.6 years (range 29-85 years), whose identified tumor stages included T2 (n = 81), T3 (n = 67), and T4 (n = 64). Relevant factors of cervical LNM were analyzed; multivariate analyses and receiver operating characteristic (ROC) curve were carried out to predict the metastasis and prognosis.

RESULTS

The overall metastatic rate of N0 GLC was 14.6%. T staging and pathological classification were the risk factors for LNM. Metastatic rates for levels II, III, and IV were 10.2%, 14.6%, and 2.5%, respectively. Approximate 4.2% of patients experienced LNM with no recurrence of laryngeal cancer. Overall 3- and 5-year survival rates were 85% and 80%, respectively, compared with 66% and 57%, respectively, among patients with LNM. The inter-group survival curve comparison was statistically significant (p = 0.012).

[Significance of frozen section diagnosis for the management of laryngeal tumors]

The frozen section procedure for immediate intraoperative pathological diagnosis represents a pivotal method in tumor diagnosis. In laryngeal tumors the most frequent indication for the use of this method is the documentation of the residual tumor status, while intraoperative consultation with the purpose of primary tumor diagnosis is less common. The specimen management employed in each case should be chosen depending on the clinical question: while the collection of a maximum amount of tissue is advisable for the determination of the residual tumor status, sparing a portion of the remaining tissue for possible future examinations is advisable in the case of primary tumor diagnosis. Moreover, intraoperative frozen section diagnosis with no immediate consequences should be avoided.