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

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.

Management and Oncologic Outcomes of Close and Positive Margins after Transoral CO2 Laser Microsurgery for Early Glottic Carcinoma

BACKGROUND

The present study analyzed the impact of margin status on local control and survival, and the management of close/positive margins after transoral CO₂ laser microsurgery for early glottic carcinoma.

METHODS

351 patients (328 males, 23 females, mean age 65.6 years) underwent surgery. We identified the following margin statuses: negative, close superficial (CS), close deep (CD), positive single superficial (SS), positive multiple superficial (MS), and positive deep (DEEP).

RESULTS

A total of 286 patients (81.5%) had negative margins, 23 (6.5%) had close margins (8 CS, 15 CD) and 42 (12%) had positive margins (16 SS, 9 MS, 17 DEEP). Among the 65 patients with close/positive margins, 44 patients underwent enlargement, 6 radiotherapy and 15 follow-up. Twenty-two patients (6.3%) recurred. Patients with DEEP or CD margins showed a higher risk of recurrence (hazard ratios of 2.863 and 2.537, respectively), compared to patients with negative margins. Local control with laser alone, overall laryngeal preservation and disease-specific survival decreased significantly in patients with DEEP margins (57.5%, 86.9% and 92.9%, p < 0.05).

CONCLUSIONS

Patients with CS or SS margins could be safely submitted to follow-up. In the case of CD and MS margins, any additional treatment should be discussed with the patient. In the case of DEEP margin, additional treatment is always recommended.

Open partial horizontal laryngectomy for T2-T3-T4a laryngeal cancer: oncological outcomes and prognostic factors of two Italian hospitals

PURPOSE

The purpose of this study was to analyse the oncologic results of open partial horizontal laryngectomy (OPHL) and to assess the prognostic factors that could affect the survival of patients affected by T2, T3 and T4a laryngeal cancer. Using this data, we aim to identify clinical criteria to select patients amenable to conservative surgery, and to facilitate a more targeted approach in the management of advanced laryngeal cancer.

METHODS

A retrospective study was performed in patients who underwent OPHL type II for laryngeal squamous cell carcinoma from January 2005 to December 2018. We analysed a total of 170 patients; 21(12.36%) cases were staged as pT2, 116 (68.23%) as pT3 and 33 (19.41%) as pT4a.

RESULTS

Five-year overall survival (OS) was 80.9%, 79.3%, 70.4% for T2, T3 and T4 respectively. Disease-specific survival (DSS) was 90.4%, 85.3% and 77.4%. Posterior tumour extension, perineural invasion and N status showed to considerably influence survival in both uni- and multivariate analyses.

CONCLUSION

The oncological outcomes from our study show that OPHL for advanced laryngeal cancer can guarantee a high percentage of success. Accurate patient selection is of utmost importance to differentiate advanced disease amenable to conservative surgery, and treatment options should consider selected criteria based on tumour and patient features.

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.

Hemoglobin Absorption Spectral Imaging (H.A.S.I.): a novel optical staining technique for microlaryngoscopy

PURPOSE

Optical image enhancement techniques are widely used in endoscopy to improve the visualization of blood vessels for diagnostic and therapeutic purposes. These techniques are monitor-based and therefore not available for direct microscopy. In this study, a novel optical microscope filter, Hemoglobin absorption spectral imaging (H.A.S.I.) was tested for use in microlaryngoscopy.

METHODS

A novel dichroic filter was designed to improve contrast in small blood vessels by highlighting transmission in the spectrum range of hemoglobin absorption maxima. A surgical microscope equipped with the novel H.A.S.I. filter was installed in one operating room in our institution. 68 consecutive patients referred to our ENT department for endoscopy were examined using white light and the novel H.A.S.I. filter during microlaryngoscopy. Surgeons described the blood vessels of the vocal cords using a classification chart and assessed for suspected malignancy using both white light and H.A.S.I.

RESULTS

77 consecutive microlaryngoscopies were performed on 68 patients. 142 vocal cords were visualized in microlaryngoscopy and the blood vessels classified according to the chart. With white light, 152 blood vessel characteristics were documented and 157 with H.A.S.I. Notably, pathologies like benign horizontal blood vessel changes, leukoplakia, and vertical blood vessel changes like dots and loops were seen more frequently with H.A.S.I. Finally, seven lesions were treated by transoral laser microsurgery (TLM) with H.A.S.I. to test the practicability of the method for microlaryngoscopic laser surgery.

CONCLUSION

This is the first study describing H.A.S.I. as an optical staining method for microlaryngoscopy. In our experience, the method was practical and improved the evaluation of vocal cord blood vessels. In some cases, the use of H.A.S.I. led to a change in diagnosis and treatment. Also, H.A.S.I. was found to be helpful in microlaryngeal laser surgery for demarcating resection margins. This is, to our knowledge, the first optical staining method integrated into a surgical microscope and can be conveniently used during microlaryngeal laser surgery and does not require further equipment.

Management of Laryngeal Dysplasia and Early Invasive Cancer

OPINION STATEMENT

Dysplasia and early laryngeal cancer lie on a spectrum of cellular changes. These start with early changes to the cells including epithelial hyperplasia and expand to dysplasia, squamous cell carcinoma in situ and finally developing in to invasive cancer. Dysplasia can range from low to high grade, with each being treated in a different manner. Treatment options are typically determined by where the dysplasia/invasive cancer lie on this spectrum along with the site within the larynx. Hyperkeratosis, mild dysplasia and moderate dysplasia typically involve primary endoscopic excision. Severe dysplasia and squamous cell carcinoma in situ involve primary endoscopic resection with the addition of possible laser resection and/or ablation. At this stage, surgery will be followed by close surveillance. Finally, early laryngeal cancer such as T1 and T2 lesions is typically more involved. Treatment depends on the site and degree of involvement of the structures, along with spread to surrounding structures. Typical treatment options of more involved early laryngeal cancer can range from radiation therapy, endoscopic transoral laser resection, endoscopic transoral robotic resection to open resection. Often times, my choice of treatment will be aimed at voice preservation but patient preference will also play a role in the decision making between treatment modalities. Chemotherapy and immunotherapy are typically not used in early stage laryngeal cancer.

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.

Narrow-Band Imaging in oncologic otorhinolaryngology: State of the art

OBJECTIVES

To describe the diagnostic performance of Narrow Band Imaging (NBI) combined with White Light Imaging (WLI) in the diagnosis of mucosal lesions at each location of the upper aerodigestive tract, for detection of primary tumor in case of carcinoma of unknown primary, for determination of intraoperative resection margins, and to describe its main diagnostic pitfalls.

MATERIAL AND METHODS

A PubMed search was carried out according to the PRISMA method.

RESULTS

Four hundred and seventy-seven articles published between 2007 and 2020 were identified, 133 of which met the study inclusion criteria and were assessed.

CONCLUSION

The current literature seems to support the use of NBI in diagnosis and/or follow-up of (pre-)malignant head & neck tumors, and in the determination of intraoperative resection margins.

Contribution of narrow band imaging in delineation of laryngopharyngeal superficial cancer spread: a prospective study

PURPOSE

The aim of this study was to assess the performance of Narrow Band Imaging (NBI) added to White Light (WL) in the delineation of laryngopharyngeal superficial cancer spread during office-based transnasal flexible endoscopy.

METHODS

This bi-centric prospective study was conducted between October 2014 and December 2017. We included consecutive patients with laryngopharyngeal malignant tumors. Transnasal flexible endoscopy was performed by two endoscopists who were blinded to each other's assessments and who examined each patient independently. The first endoscopist only performed a WL examination, while the second endoscopist carried out both WL and NBI. The extent of tumor involvement was reported based on predefined anatomical sub-units. Biopsies in NBI + /WL- sub-units were subsequently performed during panendoscopy.

RESULTS

Eighty-four patients were included in the study. A total of 72 NBI + /WL- sub-units were sampled in 38 patients, and 37 of the biopsies were positive (51.4%): 16 for invasive carcinoma, 17 for high-grade dysplasia/carcinoma in situ and 4 for low-grade dysplasia. Ultimately, 26.2% of patients had at least one positive biopsy in an NBI + /WL- sub-unit and, therefore, a better tumor delineation. The clinical T stage was upgraded in 4.8% of cases examined.

CONCLUSION

Adding NBI to WL imaging during transnasal flexible endoscopy in patients presenting with laryngopharyngeal pre-malignant or malignant lesions improves the delineation of superficial cancer spread, thereby leading to better adapted treatments. Clinicaltrials.gov registration number: NCT02035735.

Evaluating Laryngopharyngeal Tumor Extension Using Narrow Band Imaging Versus Conventional White Light Imaging

OBJECTIVE/HYPOTHESIS

Comparing detection and extension of malignant tumors by flexible laryngoscopy in the outpatient setting with laryngoscopy under general anesthesia using both White Light Imaging (WLI) and Narrow Band Imaging (NBI).

STUDY DESIGN

Prospective study.

METHODS

Two hundred and thirty-three patients with laryngeal and pharyngeal lesions underwent flexible and rigid laryngoscopy, with both WLI and NBI. Extension of malignant lesions (n = 132) was compared between both techniques in detail.

RESULTS

Sensitivity of NBI during flexible endoscopy (92%), was comparable with that of WLI during rigid endoscopy (91%). The correlation of tumor extension between flexible and rigid laryngoscopy was high (r_s  = 0.852-0.893). The observed tumor extension was significantly larger when using NBI in both settings. The use of NBI during flexible laryngoscopy leads to upstaging (12%) and downstaging (2%) of the T classification.

CONCLUSIONS

NBI during flexible laryngoscopy could be an alternative to WLI rigid endoscopy. NBI improves visualization of tumor extension and accuracy of T staging.

LEVEL OF EVIDENCE

3 Laryngoscope, 131:E2222-E2231, 2021.

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

Role of Narrow Band Imaging Endoscopy in Preoperative Evaluation of Laryngeal Leukoplakia: A Review of the Literature

INTRODUCTION

Leukoplakia is a precancerous lesion considered to be within the spectrum of histopathological results from parakeratosis, through stages of dysplasia to invasive cancer. Narrow band imaging (NBI) endoscopy has been introduced to improve early diagnosis of benign and malignant laryngeal lesions. The aim of this literature review was to evaluate the accuracy of preoperative evaluation of vocal fold leukoplakia with NBI endoscopy in comparison with histology.

METHODS

A systematic review of the literature was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, using 3 different databases: PubMed, Embase, and Scopus. The included articles in the systematic review were identified combining each of the following terms: "narrow band imaging" OR "NBI," [AND] with each of these terms: "laryngeal leukoplakia," OR "vocal fold leukoplakia," OR "vocal cord leukoplakia."

RESULTS

The articles that fully met the inclusion criteria were 5 case series, conducted between January 2010 and February 2018, and published between 2017 and 2019. The selected articles included 312 patients (86% males and 14% females), affected by 382 vocal cord leukoplakia, evaluated with NBI endoscopy and that underwent surgical microlaryngoscopy with biopsy. Based on the studies included in the review, accuracy of NBI in predicting malignancy within leukoplakia ranged from 81% to 97.8%, demonstrating to be an accurate method to predict the risk of malignant transformation of vocal fold leukoplakia.

CONCLUSION

Narrow band imaging can help otolaryngologists in the decision-making process on the necessity to perform a biopsy and transoral surgery or long-term follow-up. Larger studies are necessary to confirm the high association of NBI evaluation of the epithelium surrounding the leukoplakia with the histological diagnosis.

Management of Early Glottic Cancer Treated by CO2 Laser According to Surgical-Margin Status: A Systematic Review of the Literature

Introduction  Transoral laser microsurgery (TLM) is the treatment of choice for Tis-T2 squamous cell glottic carcinomas due to its advantages compared with open surgery and radiotherapy. However, the CO ₂ laser beam causes changes and damage on the specimens, making the histological assessment of resection margins, the gold standard for confirming radical tumor resection, sometimes difficult.

Objective  To assess the different ways to manage patients depending on the status of the histopathological margin according to recent studies to detect the most commonly shared therapeutic strategy.

Data Synthesis  We analyzed the literature available on the PubMed and Web of Science databases, including only articles published since 2005, using specific keywords to retrieve articles whose titles and abstracts were read and analyzed independently by two authors to detect relevant studies. Therefore, we focused on disease-free survival, overall survival, local control, laryngeal preservation, and disease-specific survival. Thus, 17 studies were included in the present review; they were grouped according to the status of the histological margin, and we analyzed the different management policies described in them. This analysis showed that there is not a shared strategy, though in most studies the authors performed a second-look surgery in the cases of positive margins and a close follow-up in cases of negative ones. The main disagreement is regarding the management of close or non-valuable resection margins, since some some authors performed a second-look surgery, and others, a close follow-up.

Conclusions  Definitely, the most shared policy is the second-look surgery in case of positive surgical margins, and a close follow-up in case of close or non-valuable resection margins.

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.

Transoral laser microsurgery for Tis, T1, and T2 glottic carcinoma: 5-year follow-up

The aim of this retrospective study is to evaluate the results obtained with CO₂ TOLMS in patients with Tis, T1, and T2 glottic tumors at our Department from 2004 to 2016 treated with CO₂ TOLMS. One hundred eighty-five patients having a median age of 67 years (range 42-88) were included in the present analysis. The tumor stages of the patients included 134 pTis-T1a, 12 pT1b, and 39 pT2 cases. Median duration of follow-up for the whole study cohort was 55 months (range 24-108 months). At 5-year follow-up, local control was 91%, 83%, and 79.4% for T1a, T1b, and T2 respectively. Disease-specific survival was 95.5%, 91.6%, and 92.3%. Overall survival was 73.8%, 91.6%, and 82%, and larynx preservation was 96.2%, 83%, and 84.6%. This study confirms that CO₂ TOLMS is a safe and standard therapy for selected T1 and T2 glottic carcinoma, and our review on T2 glottic cancer suggests that CO₂ TOLMS represents a reliable option in terms of overall survival, disease-specific survival, and laryngeal preservation. However, patients with anterior commissure involvement and T2 cancer should be evaluated with a preoperative MRI in order to exclude the infiltration of the laryngeal framework and to quantify the neoplastic involvement of para-glottic space.