The role of intraoperative narrow-band imaging in transoral laser microsurgery for early and moderately advanced glottic cancer

Narrow-Band Imaging in Transoral Laser Surgery for Early Glottic Cancer: A Randomized Controlled Trial

OBJECTIVE

Assessing whether the additional use of narrow-band imaging (NBI) in transoral laser surgery (TOLS) for early laryngeal cancer improves clinical outcomes.

STUDY DESIGN

Randomized controlled trial, performed between September 2015 and November 2022.

SETTING

A tertiary referral hospital in The Netherlands.

METHODS

TOLS was carried out in 113 patients. The procedure was performed with white light imaging (WLI, n = 56) alone, or combined with NBI (n = 57). Patients received frequent follow-up laryngoscopy. Resection margin status, recurrence rate, and recurrence-free survival at 12 months, 18 months, and after study termination (maximum 86 months) were analyzed.

RESULTS

Thirty-one cases in the WLI group had a positive resection margin, versus 16 in the NBI group (p = .002). After 12 months, the recurrence-free survival was 92%: 87% for WLI versus 96% for NBI, p = .07. The recurrence rate was 7/56 (13%) for WLI, versus 2/57 (4%) for NBI, p = .09. After 18 months, the recurrence-free survival was 84% for WLI versus 96% for NBI, p = .02. The recurrence rate was 9/56 (16%) for WLI, versus 2/57 (4%) for NBI, p = .02. After study termination, the recurrence-free survival was 71% for WLI versus 83% for the NBI group (p = .08). The recurrence rate was 16/56 for WLI, versus 10/57 for NBI (p = .16).

CONCLUSION

The additional use of NBI during TOLS significantly decreased the number of positive resection margins. Although not statistically significant at all time points, patients treated with NBI-supported TOLS showed a lower recurrence rate and better recurrence-free survival. Further studies in larger patient groups are needed to confirm these results.

Diagnostic Assessment (Imaging) and Staging of Laryngeal Cancer

Diagnosis of larynx cancer relies on a detailed history and physical and objective assessment with endoscopy and imaging. Endoscopy is needed to assess for vocal fold function that directly affects staging. Computed tomography and MRI can be used to assess for tumor extent in relation to intra- and extra-laryngeal structures, especially paraglottic and pre-epiglottic space involvement as well as cartilage invasion. Accurate staging is critical for subsequent treatment decision-making regarding larynx preservation.

Diagnostic Accuracy of Preoperative CT and Endoscopy Staging in Early Laryngeal Cancer

OBJECTIVES

This study aims to evaluate the diagnostic accuracy of preoperative computed tomography (CT) and intraoperative endoscopic tumor staging with regard to histopathologic staging in patients with early laryngeal cancer.

STUDY DESIGN

A retrospective nonrandomized single-institution comparative cohort study including 109 patients.

SETTING

A tertiary surgical center.

METHODS

Patients were treated for T1a, T1b, and T2a laryngeal squamous cell carcinoma by endoscopic laser surgery. The outcome measures were the presence of under- or overstaging in endoscopic and CT findings and positive postoperative margins.

RESULTS

Endoscopic overstaging as compared with histopathologic T category correlated with rising tumor category (P = .001; odds ratio [OR], 69.1) and CT findings showing anterior commissure involvement (P = .002; OR, 9.54), while endoscopic understaging correlated with rising tumor histologic grade (P = .039; OR, 4.28) and smaller tumor size (P = .011; OR, 6.39). CT overstaging vs histopathologic T category correlated with CT findings showing anterior commissure involvement (P = .001; OR, 21.76), supraglottic involvement (P = .001; OR, 59.98), subglottic involvement (P = .001; OR, 39.94), rising clinical T category (P = .01; OR, 9.11), and rising tumor histologic grade (P = .004; OR, 10.95). CT understaging as compared with histopathologic T category correlated with smaller clinical T categories (P = .002; OR, 12.72) and smaller tumor histologic grade (P = .030; OR, 7.02). Rising age, rising tumor size, anterior commissure involvement on CT, and tumor extension into the supraglottis were risk factors for positive margins.

CONCLUSION

Our results indicate that CT adds little valuable information in differentiating small superficial lesions in the glottis, while systematically overstaging cases of early laryngeal cancer. In T1a and T1b glottic tumors, endoscopy should be the preferred diagnostic method.

Intraoperative In Vivo Imaging Modalities in Head and Neck Cancer Surgical Margin Delineation: A Systematic Review

Surgical margin status is one of the strongest prognosticators in predicting patient outcomes in head and neck cancer, yet head and neck surgeons continue to face challenges in the accurate detection of these margins with the current standard of care. Novel intraoperative imaging modalities have demonstrated great promise for potentially increasing the accuracy and efficiency in surgical margin delineation. In this current study, we collated and analyzed various intraoperative imaging modalities utilized in head and neck cancer to evaluate their use in discriminating malignant from healthy tissues. The authors conducted a systematic database search through PubMed/Medline, Web of Science, and EBSCOhost (CINAHL). Study screening and data extraction were performed and verified by the authors, and more studies were added through handsearching. Here, intraoperative imaging modalities are described, including optical coherence tomography, narrow band imaging, autofluorescence, and fluorescent-tagged probe techniques. Available sensitivities and specificities in delineating cancerous from healthy tissues ranged from 83.0% to 100.0% and 79.2% to 100.0%, respectively, across the different imaging modalities. Many of these initial studies are in small sample sizes, with methodological differences that preclude more extensive quantitative comparison. Thus, there is impetus for future larger studies examining and comparing the efficacy of these intraoperative imaging technologies.

The Narrow Band Imaging as an essential complement to White Light Endoscopy in Recurrent Respiratory Papillomatosis diagnostics and follow-up process

The aim of the study is to discuss the role of NBI imaging in upper respiratory papillomatosis (RRP). In the available literature on the subject, as of 2009, there have been 117 publications on NBI imaging focusing on the diagnosis of the upper respiratory and digestive tract, especially the larynx. They discuss the following diagnostic and therapeutic problems: identifying an abnormal vascular pattern within the mucosa, differentiating benign and malignant lesions, assessing the nature of lesions under the leukoplakia plaque, pre-operative definition of laryngeal cancer margins, supporting laser procedures to obtain safe margins, postoperative monitoring after cancer treatment, detecting second simultaneous and metachronic neoplasms and primary tumors in the case of metastases from an unknown primary site. Few reports have been devoted to the assessment of the extent and recurrence of RRP. Due to its recurrent nature, this pathology deserves special attention as it requires multiple inspections and manipulation within the larynx. It also applies to the pediatric population, where there should be no margin for underestimating or overestimating changes, because any suspicion of recurrence results in subsequent general anesthesia. Hence the attempt to define an unambiguous picture of RRP recurrence and the criteria for referring for subsequent surgical treatment.

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.

Diagnostic Value of Narrow Band Imaging in Visualization of Pathological Lesions in Larynx and Hypopharynx

INTRODUCTION

Narrow Band Imaging (NBI) is an endoscopic optical imaging enhancement technology that improves the contrast of mucosal surface texture and enhances visualization of mucosal and submucosal vasculature. Due to its properties, it can visualize suspected malignant or precancerous lesions earlier than conventional white light endoscopy. The aim of this study was to analyze the benefit of NBI in visualization of precancerous and malignant lesions in preoperative and intraoperative diagnostics and correlation with histopathologic results.

METHODS

A total of 589 patients with suspicious laryngeal or hypopharyngeal lesion were investigated using conventional white light endoscopy (WLE) and NBI endoscopy with high-definition TV (HDTV NBI) from 10/2013 to 12/2019. Patients were divided into two groups based on pre-operative NBI examination (group A, 345 patients) and intraoperative NBI examination (group B, 244 patients). All suspicious lesions were graded to 5 types of Ni classification and correlated with histopathologic results. The SPSS version 8.0.4 statistical software package was used for statistical analysis. In diagnosing premalignant and malignant lesions sensitivity, specificity, positive predictive value, and negative predictive value were calculated.

RESULTS

The agreement between NBI endoscopy and histopathological analysis in group A was statistically significant (Қ = 0.76, p < 0.001), with a sensitivity of 86.2% (95% IS: 65.4-95.2) and specificity of 90.9% (95% IS: 70.6-94.1). Moreover, in group B was proven almost perfect agreement between NBI and histopathological analysis (Қ = 0.8461, p < 0.001), with a sensitivity of 84.0% (95% IS: 60.2-92.4) and specificity of 96.0% (95% IS: 87.0-99.2).

CONCLUSIONS

Based on our results, NBI using the Ni classification has great potential in improving diagnosis of precancerous and malignant lesions and correlates strongly with histopathologic results. It serves as a useful adjunct to white light endoscopy in the diagnosis of laryngeal and hypopharyngeal lesions, especially using HDTV NBI.

NBI utility in oncologic surgery: An organ by organ review

The main aims of the oncologic surgeon should be an early tumor diagnosis, complete surgical resection, and a careful post-treatment follow-up to ensure a prompt diagnosis of recurrence. Radiologic and endoscopic methods have been traditionally used for these purposes, but their accuracy might sometimes be suboptimal. Technological improvements could help the clinician during the diagnostic and therapeutic management of tumors. Narrow band imaging (NBI) belongs to optical image techniques, and uses light characteristics to enhance tissue vascularization. Because neoangiogenesis is a fundamental step during carcinogenesis, NBI could be useful in the diagnostic and therapeutic workup of tumors. Since its introduction in 2001, NBI use has rapidly spread in different oncologic specialties with clear advantages. There is an active interest in this topic as demonstrated by the thriving literature. It is unavoidable for clinicians to gain in-depth knowledge about the application of NBI to their specific field, losing the overall view on the topic. However, by looking at other fields of application, clinicians could find ideas to improve NBI use in their own specialty. The aim of this review is to summarize the existing literature on NBI use in oncology, with the aim of providing the state of the art: we present an overview on NBI fields of application, results, and possible future improvements in the different specialties.

The Impact of Narrow-band Imaging on the Pre- and Intra- operative Assessments of Neoplastic and Preneoplastic Laryngeal Lesions. A Systematic Review

Introduction  Narrow-band imaging is an endoscopic diagnostic tool that, focusing on superficial vascular changes, is useful to detect suspicious laryngeal lesions, enabling their complete excision with safe and tailored resection margins.

Objectives  To analyze the applications and benefits of narrow-band imaging in detecting premalignant and malignant laryngeal lesions through a comparison with white-light endoscopy.

Data Synthesis  A literature search was performed in the PubMed, Scopus and Web of Science databases using strict keywords. Then, two authors independently analyzed the articles, read the titles and abstracts, and read completely only the relevant studies according to certain eligibility criteria. In total, 14 articles have been included in the present review; the sensitivity, specificity, positive and negative predictive values, and accuracy of pre- and/or intraoperative narrow-band imaging were analyzed. The analysis showed that narrow-band imaging is better than white-light endoscopy in terms of sensitivity, specificity, positive and negative predictive values, and accuracy regarding the ability to identify cancer and/or precancerous laryngeal lesions. Moreover, the intraoperative performance of narrow-band imaging resulted more effective than the in-office performance.

Conclusion  Narrow-band imaging is an effective diagnostic tool to detect premalignant and malignant laryngeal lesions and to define proper resection margins. Moreover, narrow-band imaging is useful in cases of leukoplakia that may cover a possible malignant lesion and that cannot be easily assessed with white-light endoscopy. Finally, a shared, simple and practical classification of laryngeal lesions, such as that of the European Laryngological Society, is required to identify a shared lesion management strategy.

Key Points

The usefulness of the narrow band imaging (NBI) in decision-making process regarding second look procedure (SL) in laryngeal cancer follow-up after transoral laser microsurgery

Background

The prognostic value of positive surgical margins after transoral laser microsurgery (TOLM) is still under debate. In case of positive superficial margins, some experts recommend a second-look surgery (SL) and some recommend wait and watch approach with close observation. Narrow band imaging (NBI) is an advanced imaging system used to enhance visualization of mucosal vascular pattern. In laryngology, NBI is used to improve the detection of premalignant, dysplastic and malignant lesions.

Aim

To assess the usefulness of NBI imaging in guiding clinical decision making regarding follow-up plan and SL after TOLM.

Materials and methods

A prospective cohort of 127 patients was divided into three groups based on the histology results and NBI vascular pattern of the mucosa. Group A (24/127, 18.90%) consisted of patients with suspicious vascular pattern in NBI or/and with positive deep margin. Group B (52/127, 40.94%) consisted of patients with positive or uncertain superficial margins and non-suspicious vascular pattern in NBI. Group C (51/127, 40.15%) had non-suspicious vascular NBI pattern and all negative margins.

Results

After the first TOLM procedure, 9/24 (37.5%) patients had positive deep margins, 1/24 (4.2%) had uncertain deep margin and 1/24 patient (4.2%) had both positive deep margin and suspicious vascular pattern in NBI. The remaining 13 cases in Group A had a suspicious NBI finding only during the first follow-up. All of the 24 patients (Group A) underwent a second look surgery. The final histology after SL showed squamous cell carcinoma in 10/24 (41.7%) patients. All 10 patients had suspicious vascular pattern in NBI and one patient had both a positive deep margins after the first TOLM and positive NBI finding. None of Group B and C subjects developed an early recurrence.

Conclusions

Our study provides evidence that NBI imaging will be a useful adjunct to margin status after TOLM and will facilitate clinical decision-making regarding performing the SL in patients with positive or uncertain superficial surgical margins in the first TOLM procedure. However, additional investigation with more subjects is required at this time to further validate this technique and change the standard of care.

Use of narrowband imaging for the diagnosis and screening of laryngeal cancer: A systematic review and meta-analysis

We evaluated the diagnostic accuracy of narrowband imaging (NBI) in terms of detecting laryngeal cancer compared to that of white light endoscopy (WLE). Two reviewers individually searched the six databases for studies published between the first record date and December 31, 2019. We recorded the numbers of true positives, true negatives, false positives, and false negatives. Quality Assessment of Diagnostic Accuracy Studies ver. 2 software was used to assess the studies. The extent of the inter-rater agreement was also measured. The diagnostic odds ratio (OR) associated with NBI was 87.463 (95% confidence interval [CI]: 46.968, 160.873). The area under the summary receiver operating characteristic curve was 0.954. NBI was more diagnostically accurate than WLE, which was associated with a diagnostic OR of 13.750. NBI affords high diagnostic accuracy, thus supporting a role for NBI in the diagnostic work-up of laryngeal cancer.

Evaluation of narrow band imaging in the assessment of laryngeal granuloma

Laryngeal granulomas belong to common complications following trans-oral laser microsurgery (TLM). The aim of this study was to evaluate NBI in the differentiation between granuloma-like lesions and local tumor recurrence. 154 consecutive patients after TLM due to early laryngeal cancer were enrolled. In the group, a monthly follow-up including NBI endoscopy was performed. Moderate and severe dysplasia, carcinoma in situ and invasive cancer were defined as positive histology, laryngeal granuloma and other benign laryngeal lesions as negative histology and premalignant lesions as suspicious histology. In 47/154 (31%) cases, granuloma-like lesion (GLL) was found. Patients with GLL were divided into two groups based on the NBI classification. In all patients, the microvascular pattern in NBI was compared with the final histology. In group A, with suspicious, perpendicular vessels, 13/13 (100%) samples were positive. In group B, with normal vascular pattern 3/34 (9%) samples were positive and 31/34 (91%) samples were negative. There was a significant correlation between the positive NBI vascular pattern and the final histology (p = 0.00001). Sensitivity, specificity, accuracy of NBI were as follows: 81%, 100%, 94%, respectively.Based on our results, NBI can reliably differentiate between postoperative laryngeal granuloma and local tumor recurrence. In such a manner, this method is very helpful in the follow-up of tumor patients.

The Prognostic Value of Adding Narrow-Band Imaging in Transoral Laser Microsurgery for Early Glottic Cancer: A Review

BACKGROUND AND OBJECTIVES

Transoral laser microsurgery (TLM) is a universally recognized safe and minimally invasive approach for early glottic cancer. Narrow band imaging (NBI) is an optical technique working with a filtered light that reveals superficial mucosal abnormalities through the neoangiogenic pattern. The aim of this systematic review is to demonstrate the role of intraoperative NBI during TLM for early glottic cancer to better evaluate tumor extension and for more precise margin resection.

STUDY DESIGN/MATERIALS AND METHODS

A systematic review of the literature following the PRISMA guidelines was performed. A literature search was performed using the following keywords: TLM, NBI, and early glottic cancer. Two independent authors evaluated the extracted data. Data regarding status of surgical margins after TLM, local recurrence, recurrence-free survival, and need of additional samples following NBI were collected.

RESULTS

Five articles met inclusion criteria with a total of 577 patients undergoing TLM with intraoperative NBI. A significant reduction of positive superficial margins was found in patients treated with (52%) and without (28.6%) intraoperative use of NBI (P < 0.05) CONCLUSIONS: Routine use of intraoperative NBI increases the accuracy of neoplastic superficial spreading evaluation and accuracy of mass resection during TLM for early glottic cancer. The significant reduction of superficial positive margins dramatically decreases the number of patients at risk and improves clinical outcomes. Lasers Surg. Med. © 2019 Wiley Periodicals, Inc.