Imaging Modalities for Head and Neck Cancer: Present and Future

Several imaging modalities are utilized in the diagnosis, treatment, and surveillance of head and neck cancer. First-line imaging remains computed tomography (CT); however, MRI, PET with CT (PET/CT), and ultrasound are often used. In the last decade, several new imaging modalities have been developed that have the potential to improve early detection, modify treatment, decrease treatment morbidity, and augment surveillance. Among these, molecular imaging, lymph node mapping, and adjustments to endoscopic techniques are promising. The present review focuses on existing imaging, novel techniques, and the recent changes to imaging practices within the field.

Objective Comparison of White Light and Narrow-Band Imaging for Detecting Scars, Sulci and Nodules

INTRODUCTION

Narrow-band imaging (NBI) can improve detection of lesions in the aerodigestive tract. However, its role in benign lesions of the larynx is unclear. This study aims to determine whether NBI improves the detection of scars, sulci, and nodules compared to panchromatic lighting using objective image analysis.

METHODS

In total, 120 vocal folds (VFs) were analyzed with and without NBI (21 normal, 15 scars, 16 sulci, and 45 nodules). Each VF image had anterior, middle, and posterior thirds analyzed for brightness using an area morphometry software (Optimas 5.1a). The middle-third with the lesion was analyzed against surrounding VF segments for average and standard deviation (SD) in absolute grayscale.

RESULTS

The use of panchromatic light resulted in greater illumination and grayscale values than NBI. All lesions tended to be in the mid-membranous fold. Under panchromatic light, change in brightness when comparing anterior versus middle (A-M) was +6.1% for normal, versus 6.5%, 8.1%, and 7.1% for sulci, nodules, and scars, respectively. Under NBI, they were 9.0% (normal), 12.3% (sulci), 13.7% (nodules), and 13.1% (scars). A greater SD of luminescence was observed at pathology sites (p < 0.05) when using NBI. The change in absolute grayscale at all lesion sites was greater when using NBI than when using panchromatic light (p < 0.05).

CONCLUSION

NBI significantly enhanced the area of pathology in patients with nodules, sulci, and scars. Greater SD values in grayscale at pathologic sites were observed compared at normal sites. Thus, NBI may improve the detection of phonotraumatic lesions compared to panchromatic light.

LEVEL OF EVIDENCE

N/A Laryngoscope, 134:4066-4070, 2024.

The importance of preoperative and perioperative Narrow Band Imaging endoscopy in the diagnosis of pre-tumor and tumor lesions of the larynx

INTRODUCTION

Narrow band imaging (NBI) is an endoscopic imaging method intended for the diagnosis of mucosal lesions of the larynx that are not visible in white-light endoscopy, but are typical of pre-tumor and tumor lesions of the larynx.

THE PURPOSE OF THE STUDY

To compare preoperative/perioperative white light endoscopy and NBI endoscopy with the results of histopathological examinations in pre-tumor and tumor lesions of the larynx.

METHODS

A prospective study, over a period of five years (5/2018-5/2023), included 87 patients with laryngeal lesions aged 24-80 years. We evaluated preoperative/ perioperative white light and NBI endoscopy, established a working prehistological diagnosis, and compared this with the definitive histopathological results of laryngeal biopsies.

RESULTS

In relation to the definitive histology score, a statistically significant correlation was found between the evaluation of the finding and the definitive histology for preoperative and perioperative white light endoscopy and NBI endoscopy (p < 0.001). Both methods showed higher precision when used perioperatively.

CONCLUSION

NBI endoscopy is an optical method that allows us to improve the diagnosis of laryngeal lesions, perform a controlled perioperative biopsy, and refine the surgical scope. The NBI endoscopy is a suitable method for the diagnosis of early cancerous lesions of the larynx. The use of preoperative/perioperative NBI endoscopy allowed us to achieve a high level of agreement correlation (p < 0.001) between the prehistological working diagnosis and the final histopathological result. The NBI method proves its application in the diagnosis of pre-tumor and tumor lesions of the larynx.

Recurrent laryngeal papillomatosis: multimodal therapeutic strategies. Literature review and multicentre retrospective study

Objectives

Recurrent respiratory papillomatosis (RRP) is a benign, rare disease caused by Human Papilloma Virus (HPV) that can be divided into juvenile and adult forms. The course of the disease is variable, but is usually more aggressive in the juvenile form. The standard surgical treatment is represented by CO2 laser resection, although photoangiolytic lasers represent a valid alternative. Adjuvant therapies have been proposed for disease control in case of frequent surgical resections or spreading into the lower airways. In recent years, the development of immunotherapy led to the use of bevacizumab either intratumorally or intravenously, but the most promising therapeutic development is represented by HPV vaccination. This paper aims to present a narrative review of the literature and the experience of three different University Centres in the treatment of RRP.

Methods

A retrospective analysis of the clinical charts of all patients affected by laryngeal papillomatosis and treated in three different University Centres between 2002 and 2022 was performed. The following parameters were collected: sex, age at first evaluation, sites of larynx involved, HPV type, type of first surgical treatment, presence and number of recurrences, surgical treatment of recurrences, adjuvant therapies, side effects and status at last follow-up.

Results

Seventy-eight patients were available for evaluation. Of these, 88% had adult onset RRP (Ao-RRP) and 12% juvenile onset RRP (Jo-RRP). The glottis was the most frequently involved subsite; all patients were submitted to surgical resection with CO2 laser under general anaesthesia. Recurrences appeared in 79% of the patients, the patients who did not recur were all adults. The mean number of recurrences was 9 (range 1-110). Recurrences were more frequent in children (M = 20; range 2-110) than adults (M = 5; range 1-21). Thirty-two (52%) of the 62 patients who recurred were re-treated with CO2 laser under general anaesthesia, while office-based treatment with a photoangiolytic laser was preferred in the remaining 30 (48%) patients. Adjuvant treatments were applied in 26 patients. The analysis of the course of the disease showed that in the 9 patients with Jo-RRP, 6 (67%) were free of lesions at the last follow-up, while the other 3 (33%) had papillomas. Of the 69 patients with Ao-RRP, 53 (77%) were alive and free of disease at the last visit, 14 (21%) were alive with disease, 1 (1%) was lost at follow-up and 1 (1%) died for other disease. Severe side effects were not observed except for 2 patients, who developed posterior glottic stenosis.

Conclusions

Our results confirmed the literature review. RRP is a potentially aggressive disease, especially in juvenile onset. Surgical resection is still first-line treatment, but in case of multiple recurrences the use of adjuvant therapies must be taken into consideration.

Application of haemoglobin absorption spectral imaging in laryngeal papilloma surgery

OBJECTIVE

This study compares the detection rates of haemoglobin absorption spectral imaging and white light imaging in laryngeal papilloma surgery.

METHODS

Seventeen patients with laryngeal papilloma who underwent surgery in our department from September 2019 to September 2021 were selected. All patients underwent carbon dioxide laser surgery under a microscope. The lesion sites were explored in white light mode and haemoglobin absorption spectral imaging mode. The pharynx and larynx anatomical sites were evaluated using Derkay's all-position scoring system. The numbers and scores for lesions observed in the two modes were compared.

RESULTS

In 17 cases, there were statistically significant differences in the numbers of laryngeal papillomas (Derkay score) detected by white light mode and haemoglobin absorption spectral imaging mode. In 9 of 17 patients (52.94 per cent), the haemoglobin absorption spectral imaging mode showed additional diseased tissues.

CONCLUSION

The haemoglobin absorption spectral imaging mode can dynamically identify diseased tissues in carbon dioxide laser surgery under a microscope and improve the laryngeal papilloma detection rate.

Detecting Aspiration During FEES with Narrow Band Imaging in a Clinical Setting

The use of narrow band imaging (NBI) during flexible endoscopic evaluation of swallowing (FEES) is recognised as an emerging technology to improve the contrast of the test fluid during endoscopic dysphagia evaluation. This study tested the hypothesis that the use of NBI in FEES would improve the detection of laryngeal penetration and aspiration in patients with unilateral vocal fold paralysis/paresis (UVFP), a typically difficult population in which to detect the presence of aspiration with FEES. Twenty-one consecutive outpatients with UVFP were evaluated with FEES using white light (WL) and NBI under 150 test conditions (75 WL & 75 NBI). Three speech pathologists, highly experienced in FEES using WL but novices to using NBI, rated laryngeal penetration and aspiration for green dyed thin fluid (5 ml and 90 ml) and mildly thick fluid (5 ml) milk, and were compared to two raters more experienced in using NBI during FEES. Laryngeal penetration and aspiration were significantly higher for larger volumes (90 ml) (p < 0.05). With NBI-naïve raters, there was a trend towards lower intra-rater and inter-rater reliability compared to WL on all bolus trials reaching significance on mildly thick fluid (p < 0.01). There was lower rater confidence when using NBI compared to WL in NBI-naïve raters to detect aspiration (p < 0.01). Sensitivity was lower regardless of NBI experience; 80.77-84.21% with WL compared to 46.15-50.00% with NBI. Findings indicate that the improved contrast of a dyed opaque milk trial under WL may negate the potential benefits of using NBI to increase the contrast of the test fluid and supports the use of an opaque test fluid such as milk. NBI may also not be as useful to clinicians with no experience with the altered light condition, and can result in lower sensitivity in even the experienced user.

Validation of the European Laryngological Society classification of glottic vascular changes as seen by narrow band imaging in the optical biopsy setting

Purpose

In 2016, the European Laryngological Society (ELS) proposed a classification for vascular changes occurring in glottic lesions as visible by narrow band imaging (NBI), based on the dichotomic distinction between longitudinal vessels (not suspicious) and perpendicular ones (suspicious). The aim of our study was to validate this classification assessing the interobserver agreement and diagnostic test performance in detecting the final histopathology.

Methods

A retrospective study was carried out by reviewing clinical charts, preoperative videos, and final pathologic diagnosis of patients submitted to transoral microsurgery for laryngeal lesions in two Italian referral centers. In each institution, two physicians, independently re-assessed each case applying the ELS classification.

Results

The cohort was composed of 707 patients. The pathologic report showed benign lesions in 208 (29.5%) cases, papillomatosis in 34 (4.8%), squamous intraepithelial neoplasia (SIN) up to carcinoma in situ in 200 (28.2%), and squamous cell carcinoma (SCC) in 265 (37.5%). The interobserver agreement was extremely high in both institutions (k = 0.954, p < 0.001 and k = 0.880, p < 0.001). Considering the diagnostic performance for identification of at least SIN or SCC, the sensitivity was 0.804 and 0.902, the specificity 0.793 and 0.581, the positive predictive value 0.882 and 0.564, and the negative predictive value 0.678 and 0.908, respectively.

Conclusion

The ELS classification for NBI vascular changes of glottic lesions is a highly reliable tool whose systematic use allows a better diagnostic evaluation of suspicious laryngeal lesions, reliably distinguishing benign ones from those with a diagnosis of papillomatosis, SIN or SCC, thus paving the way towards confirmation of the optical biopsy concept.

The usefulness of narrow band imaging in the assessment of laryngeal papillomatosis

OBJECTIVES/HYPOTHESIS

Recurrent respiratory papillomatosis (RRP) is a benign disease caused by human papillomavirus 6 and 11. The characteristic feature of this disease are wart-like lesions covering the respiratory epithelium with a predilection for the larynx. There is no curative treatment for the disease. The goal of the treatment is a total surgical removal of the papillomatous lesions in order to reduce the number of relapses. Therefore, a good visualization method of papillomas is crucial during surgery. The aim of the study was to compare the accuracy of narrow band imaging (NBI) to the use of white light alone in detecting RRP.

METHODS

The study was carried out between April 2013 and November 2015 at Poznan University of Medical Sciences, Department of Otolaryngology, Poland. Rigid endoscopy with conventional white light (WL) and NBI (CV-260SL processor and CLV- 260SL light source, Olympus Optical Co. Ltd, Tokyo, Japan) was performed in all patients during direct laryngoscopy. All anatomical sites of the larynx and trachea were assessed using the Dikkers scale and Derkay total site scoring system with WL and NBI. The consensus was reached as to the number of lesions seen in WL compared to NBI.

RESULTS

During 36 microlaryngoscopies, the number of papillomas detected in the larynx (by Derkay total site score) differed significantly between white light endoscopy and NBI (Wilcoxon test p = 0.000655). In endoscopy with NBI, a mean of 1.3 more papillomas in Derkay total site score was detected in comparison to white light endoscopy NBI showed additional areas of diseased tissue in 15/36 (41.67%) patients.

CONCLUSIONS

NBI as an additional tool during microlaryngoscopy can improve the detection of papillomatous lesions.

Effect of Chromoendoscopy Filters on Visualization of KTP Laser-Associated Tissue Changes: A Cadaveric Animal Model

Standard KTP laser (potassium titanyl phosphate) wavelength-specific protective eyewear often impairs visualization of tissue changes during laser treatment. This sometimes necessitates eyewear removal to evaluate tissue effects, which wastes time and poses safety concerns. The objective was to determine if "virtual" or "electronic" chromoendoscopy filters, as found on some endoscopy platforms, could alleviate the restricted visualization inherent to protective eyewear. A KTP laser was applied to porcine laryngeal tissue and recorded via video laryngoscopy with 1 optical (Olympus Narrow Band Imaging) and 8 digital (Pentax Medical I-scan) chromoendoscopy filters. Videos were viewed by 11 otolaryngologists wearing protective eyewear. Using a discrete visual analog scale, they rated each filter on its ability to improve visualization,. No filter impaired visualization; 5 of 9 improved visualization. Based on statistical significance, the number of positive responses, and the lack of negative responses, narrow band imaging and the I-scan tone enhancement filter for leukoplakia performed best. These filters could shorten procedure time and improve safety; therefore, further clinical evaluation is warranted.