Role of Advanced Laryngeal Imaging in Glottic Cancer

Contact Endoscopy - Narrow Band Imaging (CE-NBI) data set for laryngeal lesion assessment

The endoscopic examination of subepithelial vascular patterns within the vocal fold is crucial for clinicians seeking to distinguish between benign lesions and laryngeal cancer. Among innovative techniques, Contact Endoscopy combined with Narrow Band Imaging (CE-NBI) offers real-time visualization of these vascular structures. Despite the advent of CE-NBI, concerns have arisen regarding the subjective interpretation of its images. As a result, several computer-based solutions have been developed to address this issue. This study introduces the CE-NBI data set, the first publicly accessible data set that features enhanced and magnified visualizations of subepithelial blood vessels within the vocal fold. This data set encompasses 11144 images from 210 adult patients with pathological vocal fold conditions, where CE-NBI images are annotated using three distinct label categories. The data set has proven invaluable for numerous clinical assessments geared toward diagnosing laryngeal cancer using Optical Biopsy. Furthermore, given its versatility for various image analysis tasks, we have devised and implemented diverse image classification scenarios using Machine Learning (ML) approaches to address critical clinical challenges in assessing laryngeal lesions.

Partial Laryngectomy for pT4a Laryngeal Cancer: Outcomes and Limits in Selected Cases

A large multi-institutional case series of laryngeal cancer (LC) T4a was carried out, including 134 cases treated with open partial horizontal laryngectomies (OPHL) +/- post-operative radiation therapy (PORT). The goal was to understand better whether OPHL can be included among the viable options in selected pT4a LC patients who refuse a standard approach, represented by total laryngectomy (TL) + PORT. All 134 patients underwent OPHL type I (supraglottic), II (supracricoid), or III (supratracheal), according to the European Laryngological Society Classification. Comparing clinical and pathological stages showed pT up-staging in 105 cases (78.4%) and pN up-staging in 19 patients (11.4%). Five-year data on overall survival, disease-specific survival, disease-free survival, freedom from laryngectomy, and laryngo-esophageal dysfunction-free survival (rate of patients surviving without a local recurrence or requiring total laryngectomy and without a feeding tube or a tracheostomy) were, respectively, 82.1%, 89.8%, 75.7%, 89.7%, and 78.3%. Overall, complications were observed in 22 cases (16.4%). Sequelae were observed in 28 patients (20.9%). No patients died during the postoperative period. This large series highlights the good onco-functional results of low-volume pT4a laryngeal tumors, with minimal or absent cartilage destruction, treated with OPHLs. The level of standardization of the indication for OPHL should allow consideration of OPHL as a valid therapeutic option in cases where the patient refuses total laryngectomy or non-surgical protocols with concomitant chemo-radiotherapy.

Surgical Treatment of Early Glottic Cancer

The incidence of all head and neck malignancies is rising worldwide, with carcinoma of the larynx constituting approximately 1% of all cancers. Early glottic cancer responds quite favorably to surgical intervention due to its early presentation, coupled with the low rate of regional and distant metastases. This article focuses on various approaches to the surgical treatment of early glottic cancer. Details include the clinical and radiological evaluation of laryngeal cancer, the goals of treatment, current surgical options for early disease, approach to surgical resection margins and management of nodal disease, and complications associated with each treatment modality.

Dysplastic Lesions of the Larynx

There have been many advancements in the clinical and histologic diagnosis of laryngeal dysplasia (LD), but diagnosis still necessitates invasive histologic evaluation. Furthermore, despite improved histologic identification of dysplastic lesions, the exact details of pathophysiologic progression and the risk of malignant transformation is still uncertain. These unknowns create a barrier to establishing an ideal grading and classification system, which prevents the establishment of a precise and consistent treatment paradigm. Identifying these gaps in knowledge serves to highlight where further studies are warranted, ideally focusing on a better understanding of the biological behavior of LD. This would ultimately allow for the creation of a reliable grading and classification system and for the formalization of management and treatment guidelines for LD.

Current Intraoperative Imaging Techniques to Improve Surgical Resection of Laryngeal Cancer: A Systematic Review

Simple Summary

Laryngeal cancer is a prevalent head and neck malignancy, with poor prognosis and low survival rates for patients with advanced disease. The recurrence rate for advanced laryngeal cancer is between 25 and 50%. In order to improve surgical resection of laryngeal cancer and reduce local recurrence rates, various intraoperative optical imaging techniques have been investigated. In this systematic review we identify these technologies, evaluating the current state and future directions of optical imaging for this indication. Evidently, the investigated imaging modalities are generally unsuitable for deep margin assessment, and, therefore, inadequate to guide resection in advanced laryngeal disease. We discuss two optical imaging techniques that can overcome these limitations and suggest how they can be used to achieve adequate margins in laryngeal cancer at all stages.

Abstract

Laryngeal cancer is a prevalent head and neck malignancy, with poor prognosis and low survival rates for patients with advanced disease. Treatment consists of unimodal therapy through surgery or radiotherapy in early staged tumors, while advanced stage tumors are generally treated with multimodal chemoradiotherapy or (total) laryngectomy followed by radiotherapy. Still, the recurrence rate for advanced laryngeal cancer is between 25 and 50%. In order to improve surgical resection of laryngeal cancer and reduce local recurrence rates, various intraoperative optical imaging techniques have been investigated. In this systematic review, we identify these technologies, evaluating the current state and future directions of optical imaging for this indication. Narrow-band imaging (NBI) and autofluorescence (AF) are established tools for early detection of laryngeal cancer. Nonetheless, their intraoperative utility is limited by an intrinsic inability to image beyond the (sub-)mucosa. Likewise, contact endoscopy (CE) and optical coherence tomography (OCT) are technically cumbersome and only useful for mucosal margin assessment. Research on fluorescence imaging (FLI) for this application is sparse, dealing solely with nonspecific fluorescent agents. Evidently, the imaging modalities that have been investigated thus far are generally unsuitable for deep margin assessment. We discuss two optical imaging techniques that can overcome these limitations and suggest how they can be used to achieve adequate margins in laryngeal cancer at all stages.

[Current diagnostic imaging and treatment planning for laryngeal cancer]

CLINICAL/METHODICAL ISSUE

Laryngeal cancer is the third most common malignancy in the head and neck region. Endoscopic laryngoscopy with assessment of vocal fold function, microlaryngoscopy with biopsy and computed tomography (CT)/magnetic resonance imaging (MRI) remain the cornerstones of diagnostic workup. Thus, in the context of therapy planning, consideration of individual functional and socioeconomic aspects is of major importance.

STANDARD RADIOLOGICAL METHODS

Due to the short acquisition time and the possibility to perform functional maneuvers, CT is the tool of choice. MRI allows better soft tissue differentiation, but is more susceptible to movement artifacts and is complicated by disease-specific symptoms. The choice of examination method therefore depends on the patient's physical resilience.

PERFORMANCE

Depending on the study, the information on the sensitivity of CT with regard to the question of cartilage infiltration varies between 62 and 87% with a specificity between 75 and 98%. For MRI, sensitivity between 64 and 95% and specificity between 56 and 88% are stated.

ACHIEVEMENTS

The synthesis of the findings from endoscopy, biopsy and imaging is prerequisite for initiation of stage-appropriate treatment. For image interpretation, knowledge of the anatomical landmarks is essential. However, the assessment of posttherapeutic changes also poses a challenge for the radiologist.

PRACTICAL RECOMMENDATIONS

Regular interdisciplinary dialogue between radiologists, otorhinolaryngologists and radiotherapists in the context of primary diagnostics, therapy planning and aftercare is essential.

RNA-binding protein RBM6 as a tumor suppressor gene represses the growth and progression in laryngocarcinoma

Aberrant expression of RBM6 has been implicated in the development of human malignancies. However, the bio-function of RBM6 in laryngocarcinoma is still almost blank. Here we identified that RBM6 was downregulated in laryngocarcinoma tissues, as well as laryngocarcinoma cell lines. Notably, the expression level of RBM6 was lower in laryngocarcinoma patients at stage3/4 than that in laryngocarcinoma patients at stage1/2. Upregulation of RBM6 suppressed the proliferation of TU212 and Hep-2 cells, as shown by decreased cell viability and Ki67 level. In parallel, overexpression of RBM6 inhibited invasion and promoted apoptosis of TU212 and Hep-2 cells, as evidenced by downregulation of MMP-2 and MMP-9 protein expression and upregulation of cleaved caspase-3 protein expression. In vivo, RBM6 overexpression repressed the laryngocarcinoma tumor growth. EGFR mRNA level was higher in the laryngocarcinoma tissues than that in the adjacent normal tissues. Moreover, upregulation of RBM6 reduced the expression of EGFR, ERK and p-ERK in vitro and in vivo. Our data suggest that RBM6 as a tumor suppressor represses the growth and progression in laryngocarcinoma.

The value of narrow band imaging combined with stroboscopy for the detection of applanate indiscernible early-stage vocal cord cancer

BACKGROUND

Narrow band imaging (NBI) and stroboscopy are non-invasive techniques to detect the malignant lesions of the vocal cord. This study was to assess the diagnostic value of combined endoscopic analysis in the applanate indiscernible early-stage vocal cord cancer.

METHODS

A total of 110 patients with 160 suspicious vocal cord malignant lesions were included in this retrospective study. Stroboscopy was immediately performed after NBI and white light endoscopy (WLE) were performed in all patients. Excisional biopsy was performed to examine histopathology examination.

RESULTS

We found that the diagnostic specificity and PPV were higher in the NBI and WLE combined with stroboscopy group than in the NBI and WLE group without stroboscopy (88.9% vs 72.5%, 88.4% vs 60.9%). However, the diagnostic sensitivity was not significantly different in those two groups (69.3% vs 67.7%).

CONCLUSION

NBI and WLE combined with stroboscopy is a promising method to detect early-stage vocal cord cancer with the advantage of clinical feasibility and diagnostic specificity.

[Robotic Surgery - Who is The Boss?]

In the head and neck region, great potential is seen in robot-assisted surgery (RAS). Mainly in cancer surgery, the use of robotic systems seems to be of interest. Until today, two robotic systems (DaVinci® und FLEX®) have gained approval for clinical use in the head and neck region, and multiple other systems are currently in pre-clinical testing. Although, certain groups of patients may benefit from RAS, no unbiased randomized clinical studies are available. Until today, it was not possible to satisfactorily prove any advantage of RAS as compared to standard procedures. The limited clinical benefit and the additional financial burden seem to be the main reasons, why the comprehensive application of RAS has not been realized so far.This review article describes the large variety of clinical applications for RAS in the head and neck region. In addition, the financial and technical challenges, as well as ongoing developments of RAS are highlighted. Special focus is put on risks associated with RAS and current clinical studies. We believe, that RAS will find its way into clinical routine during the next years. Therefore, medical staff will have to increasingly face the technical, scientific and ethical features of RAS.

Computed Tomography Versus Magnetic Resonance in Head and Neck Cancer: When to Use What and Image Optimization Strategies

This article provides a practical overview of head and neck cancers, outlining an approach to evaluating these lesions and optimizing imaging strategies. Recognition of key anatomic landmarks as suggested by American Joint Committee on Cancer (AJCC) tumor, node, metastasis (TNM) criteria is emphasized. Further, the recently updated eighth edition of the AJCC staging manual has introduced some modifications that influence the TNM staging. These modifications are discussed throughout the article to provide an updated review on head and neck cancer.

[Imaging for surgical planning : Tumor surgery including reconstructive procedures]

Alongside clinical investigation, imaging is an important diagnostic modality for guiding treatment decisions and particularly for surgical planning in head and neck cancer. The significance and type of imaging depends on localization of the primary tumor. Beside the primary tumor, each imaging procedure must also include the lymph nodes, in order to develop an overall concept of surgical treatment. In addition to the superficial growth of a tumor, it is of utmost importance that its infiltration also be detected by imaging, in order to define the extent of tumor resection and identify potentially necessary reconstructive procedures. The type of imaging needed to understand tumor localization and size, e.g., CT or MRI, depends on the region. In some cases the methods are complementary.

Reasonable limits for transoral laser microsurgery in laryngeal cancer

PURPOSE OF REVIEW

Transoral laser microsurgery (TLM) is widely acknowledged to offer several advantages in the treatment of early and selected intermediate-advanced laryngeal cancers. Nevertheless, a number of issues are still under debate. The purpose of this review is to discuss the reasonable limits for TLM in laryngeal cancer to highlight its most appropriate and reproducible indications, putting this therapeutic tool in the right perspective within a comprehensive frame of alternative treatment strategies such as open partial laryngectomies and nonsurgical organ preservation protocols.

RECENT FINDINGS

Inadequate laryngeal exposure, anterior commissure involvement in the cranio-caudal plane (T2), invasion of the posterior paraglottic space with arytenoid fixation, massive infiltration of the preepiglottic space, and even minor thyroid cartilage erosion (T3) represent the most controversial applications of TLM in management of glottic and supraglottic cancer.

SUMMARY

Published oncological results appear to be satisfactory when TLM is applied to T1-T2 and accurately selected T3 glottic and supraglottic cancers with favourable exposure. Caution should be used for more advanced tumours.