Clinical applicability of the Ljubljana classification of epithelial hyperplastic laryngeal lesions

The Comparison of Narrow Band Imaging, White Light Laryngoscopy and Videolaryngostroboscopy in the Evaluation of Benign Vocal Fold Lesions

BACKGROUND

The aim of the study was comparing the diagnostic role of the white light (WL) endoscopy, video laryngostroboscopy (VLS), and narrow-band imaging (NBI) in the evaluation of the benign vocal fold lesions.

MATERIAL AND METHODS

From March 2018 to June 2019, a total of 118 cases were enrolled in this study. Ninety-eight patients were suspected with vocal fold nodules, cysts, polyps, and sulcus vocalis and 20 patients without a history of dysphonia. Each patient was examined by WL, VLS, and NBI endoscopy. Recorded images and videos were analyzed and scored by three otorhinolaryngologists who had at least 3 years of experience in phoniatrics field. The evaluation results were compared between the methods and the physicians.

RESULTS

A total of 118 cases were grouped by their confirmed diagnosis, vocal fold nodules (n = 28), vocal fold cyst (n = 24), vocal fold polyp (n = 9), and sulcus vocalis (n = 37). When the correct diagnosis rates of the physicians were compared, the statistical significance was found between the physicians in the WL and VLS method (P= 0.014, P= 0.027). No statistically significant difference was found among physicians in NBI method (P = 0.368). The difference between the diagnostic methods was found to be statistically significant in reaching the accurate diagnosis for benign vocal fold lesions (P< 0.001). While the difference between NBI-WL and VLS-WL was statistically significant (P< 0.001 and P< 0.001). The difference between NBI-VLS was not statistically significant while evaluating the vocal fold nodules, cysts, and sulcus vocalis separately (P= 0.102, P = 0.026, P = 0.157). Otherwise, it was statistically significant (P= 0.002) while evaluating total benign lesions in the study. The difference between NBI-VLS combination and VLS, NBI-VLS combination and VLS-WL combination were statistically significant (P< 0.001 and P= 0.001).

CONCLUSION

This study showed that NBI assessments have similar accuracy and sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) to VLS and have a higher value than WL endoscopy in reaching the diagnosis for benign vocal fold lesions. Therefore, NBI can be accepted as a promising approach to identify benign laryngeal lesions due to its optical properties.

Oral epithelial dysplasia: Classifications and clinical relevance in risk assessment of oral potentially malignant disorders

After more than a decade, the World Health Organization (WHO) published the revised grading system for oral epithelial dysplasia in 2017. The revised classification has changes reflecting our evolution of understanding of the dysplastic process. Although the WHO 2017 three-tier grading system is the gold standard for histological diagnosis of oral potentially malignant disorders, it has certain limitations. Suggestions to overcome these limitations include the use of clinical determinants and molecular markers to supplement the grading system. It has also been suggested that a two-tier system may be more reproducible and clinically translatable for better management. These advances in the understanding of epithelial dysplasia are very important globally and for us in the Indian subcontinent, given the prevalence of habits (tobacco/areca nut) and burden of oral cancer in this part of the world. The following review traces the evolution of the grading system of dysplasia, its relevance and clinical utility.

A comparative histopathological study of vocal fold polyps in smokers versus non-smokers

BACKGROUND

A large proportion of patients with vocal fold polyps are cigarette smokers. However, prior to this report no comparative study of polyp histopathology in smokers versus non-smokers had been performed.

METHODS

A prospective histopathological study of vocal fold polyps excised from 29 patients was undertaken. This comprised a comparative analysis of polyp histopathology in smokers versus non-smokers and a review of the pertinent literature.

RESULTS

Vocal fold polyps were larger in smokers than in non-smokers. Histopathological features significantly associated with the polyps of smokers versus those of non-smokers were increased keratinisation, dysplasia, a basement membrane thinning and hyaline degeneration.

CONCLUSION

Cigarette smoke has an injurious effect on vocal fold polyp epithelium and leads to increased hyaline degeneration in polyps.

Oral premalignant lesions: from the pathological viewpoint

Under the widely used World Health Organization (WHO) classification for the pathological diagnosis of oral premalignant lesions, dysplasia, which is graded as mild, moderate or severe, and carcinoma in situ (CIS), which is a non-invasive carcinoma, are classified as precursor lesions of oral squamous cell carcinoma. Since the first edition (Wahi et al. International histological classification of tumours no. 4, WHO, Geneva, 1971), the criterion for CIS--that all epithelial layers are replaced by atypical cells--has remained unchanged. However, this dysplasia-carcinoma sequence theory was introduced from the viewpoint of pathological changes in the uterine cervix: in contrast, almost all premalignant lesions and CIS of the oral mucosa show superficial maturation and differentiation. Based on this recognition, the squamous intraepithelial neoplasia (SIN) classification and Ljubljana classification were included in WHO's latest edition published in 2005. Although the WHO classification is commonly used in Japan, recent developments in oral oncology have promoted modifications of the classification used in this country. In 2005, the Working Group of the Japan Society for Oral Tumours advocated iodine staining and proposed a modified SIN system, and in 2007, the Working Committee of the Japanese Society for Oral Pathology (JSOP) reported a new CIS (JSOP) definition that included differentiated-type CIS. In 2010, based on these studies, a new entity--oral intraepithelial neoplasia (OIN)--was included in the first edition of General Rules for Clinical and Pathological Studies on Oral Cancer. In this review, we focus on the OIN/CIS (JSOP) new classification of premalignant lesions in oral mucosa, which further advances the concept of SIN.

Vocal fold nodules: morphological and immunohistochemical investigations

The objective of this study was to investigate the morphological and immunohistochemical characteristics of vocal fold nodules. The study design was prospective and retrospective. For the histological study, we reviewed 15 slides from the surgical cases of vocal fold nodules, in which we analyzed epithelium, basal membrane (bm), and lamina propria. For the transmission and scanning electron microscopy (TEM, SEM) studies, five new cases on vocal fold nodules were included. Immunohistochemistry study was carried out in the 15 specimens, using antifibronectin, antilaminin, and anticollagen IV antibodies. The main histological alterations were epithelial hyperplasia (73.33%), basement membrane thickening (86.66%), edema, and fibrosis (93.33%). SEM--reduction in mucous lacing and increase in the desquamating cells, without epithelial erosion. TEM--hyperplasia of the epithelium, enlargement of the intercellular junctions, which was filled by fluid, subepithelial thickening of the lamina reticularis, and break points in the basal membrane. Immunohistochemistry--we identified greater immunoexpression of fibronectin on the basal membrane, on the lamina propria, and around the vessels. Antilaminin and anticollagen IV antibodies showed higher pigmentation on the endothelium of the vessels than that on the basal membrane. In vocal fold nodules, combined assessment using light microscopy, electron microscopy, and immunohistochemistry can reveal important morphological details useful in characterizing these lesions.

[Application of Ljubljana classification in laryngeal precancerous lesions]

The diagnosis and treatment of laryngeal premalignant lesions has been frustrated because of failure to adequately define the histologic changes that may help in prediction of irreversible neoplastic transformation. To assess the grading of laryngeal hyperplastic epithelial lesion it was used a Ljubljana classification of histologic changes. It was done a retrospective study of 104 laryngeal hyperplastic lesions biopsies that were classified according to the Ljubljana classification comprising benign spinous layer augmentation (simple hyperplasia), benign basal and parabasal layer augmentation (abnormal hyperplasia), alteration of epithelial cells towards malignancy (atypical hyperplasia) and carcinoma in situ. One hundred and four biopsies with preneoplastic changes were reevaluated and classified according to Ljubljana classification. It was found 42 cases (40.4%) which showed simple, 38 (36.5%) abnormal, 21 (20.2%) atypical hyperplasia and 3 (2.9%) carcinoma in situ. Three cases of atypical hyperplasia (2.9% of all investigated cases) and one of abnormal (0.96%) progressed to invasive carcinoma during the observation ranging from 5 to 9 years (median 8.1). None of the cases classified as simple hyperplasia showed progression to malignancy. The Ljubljana classification focuses on the important clinical decision involving benign looking hyperplastic lesion that do not require strict follow-up (simple and abnormal hyperplasia); and "risky" epithelium that require close follow-up with repeated histologic assessment to recognize any malignant progression (atypical hyperplasia); and carcinoma in situ that requires fast and complete treatment. We suggest that the Ljubljana classification may give a reliable assessment of laryngeal hyperplastic epithelial lesions and can help in monitoring all those patients.

Immunohistological comparison of the World Health Organization (WHO) and Ljubljana classifications on the grading of preneoplastic lesions of the larynx

There is still controversy about the classification of laryngeal preneoplastic lesions. In this study, we compared the World Health Organization (WHO) and Ljubljana histological classifications with regard to laryngeal epithelial hyperplastic-dysplastic lesions in a single series to determine their relation to statistically significant criteria when the mechanisms of neoplastic progression are considered. Emphasis was put on p53 expression, proliferative activity, and angiogenesis. Fifty-four laryngeal biopsies with preneoplastic changes were re-evaluated and classified according to both classifications. The streptavidin-biotin method was used for immunohistochemical staining for Ki-67, p53, and CD34 antibodies. A positive correlation was obtained between the histological categories and Ki-67, p53, and CD34 expressions using both classifications (Spearman's Correlation test). There was a significant difference between the histological categories of both the WHO and the Ljubljana classifications, when the expression of the three markers was compared (Kruskal Wallis test, p = 0.000 for each). Further evaluation revealed a statistically significant difference between all categories of both classifications, excluding the p53 overexpression scores and vessel counts in mild and moderate dysplasia categories (Mann-Whitney U-test, p = 0.209, and 0.091 respectively), and the p53 overexpression scores in severe dysplasia and carcinoma in situ categories (Mann-Whitney U-test, p = 0.249) of the WHO classification. Similarly, no significant differences were found between severe dysplasia and carcinoma in situ, as well as between atypical hyperplasia and carcinoma in situ categories using both classifications for the Ki-67 expression (Mann-Whitney U-test, p = 0.806, and 0.111, respectively). Our results suggest that regarding the mechanisms of neoplastic progression such as p53 expression and angiogenesis, the histological categories of the Ljubljana classification seem to depend on additional evidence. Therefore, we support the use of the Ljubljana classification.

The supplementary diagnostic power of selected immunohistochemical, molecular genetic and infective parameters in epithelial hyperplastic laryngeal lesions

OBJECTIVES

MIB-1 and p53 protein expression, loss of heterozygosity (LOH), microsatellite instability (MSI) of di- and mononucleotide repeats, and HPV status were tested for their potential to characterize different stages of epithelial hyperplastic laryngeal lesions (EHLL).

METHODS

Thirty-two EHLL were reclassified according to the Ljubljana classification into simple (SH), abnormal (AbH), atypical hyperplasia (AtH) and carcinoma in situ, and investigated by immunohistochemical methods, PCR and direct sequencing analysis.

RESULTS

MIB-1 increased with progressive grades of EHLL, whereas p53 protein expression was distinctive only between SH and AbH. LOH showed increasing frequency with grades of the lesions, but the distribution of altered loci (9p, 9q, 10q, 11q, 17p) was not qualified to differentiate between the stages. MSI was detected in SH, AbH and AtH without clear correlation to histopathological grading. HPV infection occurred mostly in SH and AbH (both: 66.7%).

CONCLUSION

MIB-1 labeling and allelic loss could assist histopathological diagnosis in the entire spectrum of EHLL, whereas the MSI results point to a genetic instability of the laryngeal mucosa in general and are therefore not helpful in the distinction of different stages of EHLL. However, future molecular genetic analyses should consider more late events of laryngeal carcinogenesis to improve their diagnostic potential. Furthermore, our results indicate that nonrisky and risky EHLL could probably be caused by different exogenous factors.

The Ljubljana classification - its application to grading oral epithelial hyperplasia

INTRODUCTION

The diagnosis, prognosis and treatment of particular pathologic entities of the oral mucosa depend almost exclusively on the histologic changes in the epithelium. The basis for the classification of oral epithelial hyperplastic lesions should be their propensity to progress to invasive cancer.

MATERIAL AND METHODS

In a retrospective study, 135 biopsies of oral epithelial hyperplastic lesions from 115 patients were classified according to the Ljubljana classification, which has recently been introduced for the grading of laryngeal hyperplastic epithelial lesions.

RESULTS

Seventy nine cases (59%) showed simple, 42 (31%) abnormal and 11 (8%) atypical hyperplasia; carcinoma in situ was found in three cases (2%). During the follow-up, ranging from 3 months to 6 years (median 1 year), two cases of atypical hyperplasia progressed to invasive cancer, whereas none of the cases classified as simple or abnormal hyperplasia showed progression.

CONCLUSION

The present study suggests that the Ljubljana classification can be reliably applied for classifying oral epithelial hyperplastic lesions into different risk groups, which is essential for prognosis in order to plan therapy.