Background: Leukoplakia is a premalignant lesion and it is considered a hyperplastic and dysplastic phase of epithelial evolution in the glottic larynx, especially in this cas at the vocal fold level. The leukoplakia may or may not evolve into a carcinoma. Regarding the epidemiology of premalignant lesions, the data found in the literature are scarce.

Objective: The purpose of this study was to determine the accuracy of preoperative examination for diagnosing premalignant laryngeal lesions and their association with benign vocal fold diseases. Methods: This is a transversal study performed through the review of surgical records and anatomopathological study of patients who underwent laryngeal microsurgeries in the period of 30 years (1990 to 2019) by a single surgeon.

Results: Premalignant lesions were more prevalent in men (68.7%) and in ages 51 to 60 years (30.3%). Males were more prevalent (69,49%) than females (30,51%). The average age was 47,74 years and the median was 47 years (20 to 85 years). The predominant age bracket was between 41 and 50 years. In females, premalignant lesions occurred most often in the fifth and the sixth decades of life. In males, in the fourth and fifth decades.

Conclusion: When considering this sample, it is clear that around 13% of premalignant lesions are only diagnosed from laryngeal microsurgery. Furthermore, there has been an increase in the prevalence ratio in the last 10 years (9.85% to 18.12%), this fact may be due to attention to the association of diseases, interactivity with the pathologist and the application of new technologies.

D’Avila JA, D’Avila DV, Setton ARF, De Góis CRT, De Oliveira Meurer AT, et al. (2024) Vocal Fold Leukoplakia - 30 Years of Experience and Critical Analysis. Ann Otolaryngol Rhinol 11(4): 1340.

Leukoplakia is a premalignant lesion and it is considered a hyperplastic and dysplastic phase of epithelial evolution in the glottic larynx, especially in this case at the vocal fold level [1- 3]. The leukoplakia may or may not evolve into a carcinoma. In the clinical practice, they are commonly classified as a leukoplakia, erythroplakia, erythroleukoplakia, and chronic laryngitis, although there is no consensus on this issue [4]. Regarding the epidemiology of premalignant lesions, the data found in the literature are scarce. However, it is known that these lesions are more prevalent in males and it usually affects individuals above 50 years of age. There is a direct relationship between a leukoplakia and the following conditions: age and gender, alcoholism, smoking, bad vocal use, reflux disease, and papilomatosis [5]. Other diseases may present with a similar aspect. The differential diagnosis includes tuberculosis, secondary syphilis, pseudomembranous moniliasis, chemical irritants inhalation, and deep mycoses. Its most important symptom is progressive hoarseness, among others such as dry cough, sore throat and hawking. Leukoplakia is diagnosed by outpatient laryngoscopic examination, which provides a safe and easy evaluation of laryngeal pathologies [6-9].The evolution of laryngoscopic procedures in outpatients has provided better access to important information for a safe and easy diagnosis of laryngeal pathologies. Preoperative assessment procedures have also evolved, and the introduction of new endoscopic methods is providing more informative analyses of lesions of the vocal folds [10]. The dissociation between the diagnostic imaging in the preoperative and transoperative periods in patients submitted to laryngeal microsurgery has been observed in the clinical practice, especially with respect to benign lesions of the vocal folds [11,12]. Neither comparisons concerning premalignant lesions nor studies regarding the concomitance of benign and premalignant laryngeal lesions are found in the medical literature.The purpose of this study was to determine the accuracy of preoperative examination for diagnosing premalignant laryngeal lesions and their association with benign vocal fold diseases, as well as to evaluate their epidemiological characteristics.

This is a transversal study performed through the review of surgical records and anatomopathological study of patients who underwent laryngeal microsurgeries in the period of 30 years (1990 to 2019) by a single surgeon. In the first 20 years (1990 to 2009), the methodology followed this order: analysis of medical records of patients, microsurgery image and REMS, and pathological anatomical study. For the last 10 years (2010 to 2019), the order of analysis was inverted: pathological anatomical study, microsurgery image and REMS, and medical records of patients. Anamnesis and physical examinations were performed in all patients. All of them complained of hoarseness and underwent flexible nasopharyngolaryngoscopic assessment (Machida ENT—30P III, Machida Endoscope Co., Japan) and rigid telescopic laryngoscopy using a 70-degree, 10- mm Storz telescope (Karl Storz GmbH & Co. KG, Germany) with stroboscopic light source to obtain preoperative diagnostic imaging. The equipment was coupled to a video system for the morphologic characterization, localization of the lesion, and documentation. Laryngeal microsurgery was performed in the operating room under general anesthesia. A Bouchayertype suspension laryngoscope was used together with a DF Vasconcelos microscope (D.F. Vasconcellos S.A., São Paulo, Brazil) (400-mmlens, 16x or 24x magnifications). Laryngeal microscopy was performed by suspension laryngoscopy, making a thorough inspection, classic palpation maneuvers, and eversion of laryngeal structures using specific instruments for this purpose. Those patients who underwent the surgery after 2000 were submitted to rigid endoscopy with 0-, 30-, 70-, and 120-degree endoscopes and contact endoscopy with specific 0-degree endoscope (Karl Storz GmbH & Co. KG, Germany). After defining the transoperative diagnostic imaging, lesions were completely excised and subsequently placed separately in 10% formaldehyde solution and forwarded to the pathology laboratory on the same day.

As inclusion criteria, we considered patients who had the following records in transoperative diagnostic imaging confirmed with postoperative anatomopathological exam: leukoplakia, erythroplakia, hyperkeratosis, leukoerythroplakia, dysplasia, and chronic laryngitis. The exclusion criteria considered patients who did not have records of preoperative diagnostic imaging or confirming postoperative anatomopathological exam. The following data were collected: preoperative diagnostic imaging, trans operative diagnostic imaging, sex, and age. This study followed the ethical recommendations for research involving human beings advocated in the Resolution No. 196/96 of the National Health Council. It was submitted and approved by the Research Ethics Committee of the institution, under Protocol CAAE-1103.0.107.00007. Data collection was only performed after the consent of the committee.

A total of 910 patients were submitted to laryngeal microsurgery in the service from 1990 to 2019 [Table 1]. According to the methodology proposed in the first 20 years, 59 patients with premalignant lesions of the vocal folds were selected, which represented 9.85% of the sample. In the last 10 years, 62 were selected, representing 18.12% of the sample. In the total sample, 12.96% of the patients presented with premalignant lesions [Table 1].

Table 1: Leukoplakia in 30 years

The preoperative evaluation of outpatients obtained an accuracy of 68.8%. Patients who had premalignant lesions accounted for 10.87% of those who underwent laryngeal microsurgery. The association of leukoplakia with benign disease accounted for 12.96% of patients who underwent laryngeal microsurgery in thirty years. Vocal fold cysts were the most frequently associated benign lesions [Figure 1].

Figure 1: Concomitant benign lesions of the vocal folds in patients with premalignant laryngeal lesions

Premalignant lesions were more prevalent in men (68.7%) and in ages 51 to 60 years (30.3%). Males were more prevalent (69,49%) than females (30,51%). The average age was 47,74 years and the median was 47 years (20 to 85 years). The predominant age bracket was between 41 and 50 years. In females, premalignant lesions occurred most often in the fifth and the sixth decades of live. In males, in the fourth and fifth decades.

Premalignant lesions are more prevalent in men over 40 years old (almost 70 %), and it usually has a direct relationship with smoking, alcoholism, and vocal abuse. These data agree with the literature [1,5,10].

This prevalence is justified due to the surgeon’s special attention during the trans-operative period, and the following aspects were observed: the leukoplakia may be microscopic, it may be located throughout the glottis, especially at the vocal fold level, it may be associated to the initial surgical lesion, it may be contralateral to it, it may be located in the epithelium of this lesion or it may also be subglottic. Intraoperative staging with microscopy, palpation maneuvers and the use of rigid endoscopes angled at 30, 70 and 120 degrees favor the detection of leukoplastic lesions [Figures 2-5].

Figure 2: Leukoplakia with variation in location and quantity

Figure 3: Leukoplakia with variation in location and quantity

Figure 4: Leukoplakia with variation in location and quantity

Figure 5: Leukoplakia with variation in location and quantity

There are different perspectives of the same lesion when 0, 30, 70 and 120 degree angled endoscopes are used [Figures 6-9]. 

Figure 6: Leukoplakia with variation in location and quantity. 0 degree

Figure 7: Leukoplakia with variation in location and quantity. 30 degree

Figure 8: Leukoplakia with variation in location and quantity. 70 degree

Figure 9: Leukoplakia with variation in location and quantity. 120 degree

It is fundamental to understand that, in the same patient with leukoplakia, and even in the same leukoplakia plaque, there can be various degrees of dysplasia evolution, including the association of grade I dysplasia with invasive carcinoma. There was an increase in the prevalence ratio in the last 10 years (from 9.85% to 18.12%). This may be due to the attention to the association of disease, interactivity with the pathologist, and application of new technologies such as REMS and CEMS. However, the prevalence in relation to gender, age, and etiological factors were statistically similar in 30 years of research.

When considering this sample, it is clear that around 12.96% of premalignant lesions are only diagnosed from laryngeal microsurgery, therefore, despite being low, the rate of diagnosis of premalignant lesions has a great impact on the clinical management of the patient in question. Furthermore,there has been an increase in the prevalence ratio in the last 10 years (9.85% to 18.12%), this fact may be due to attention to the association of diseases, interactivity with the pathologist and the application of new technologies such as REMS and CEMS cysts were the most prevalent concomitant benign lesions of the vocal fold. Males were more prevalent and the predominant age group was between 51 and 60 years old.

We are endlessly grateful for the honorable contribution of the eternal Masters Prof. Dr. Mário Andrea, Oscar Dias and Alberto Santos from the University of Lisbon - Portugal. Without their unparalleled guidance and dedication, this work would not be possible. Our utmost gratitude

1. Parker NP.Vocal fold leukoplakia: incidence, management, and prevention. Curr Opin Otolaryngol Head Neck Surg. 2017; 25: 464- 468.

2. Garrel R, Uro Coste E, Costes-Martineau V, Woisard V, Atallah I, Remacle M.Vocal-fold leukoplakia and dysplasia. Mini-review by the French Society of Phoniatrics and Laryngology (SFPL). Eur Ann Otorhinolaryngol Head Neck Dis. 2020;137:399-404

3. Rutt AL, Wang C, Zhuo Li. Clinicopathologic Aspects of Vocal Fold Leukoplakia in Smokers and Nonsmokers. J Voice. 2021; 35:779-784.

4. Nina Gale , Leslie Michaels, Bostjan Luzar, Mario Poljak, Nina Zidar, Janez Fischinger,et al. Current review on squamous intraepithelial lesions of the larynx. Histopathology. 2009; 54: 639–656.

5. Padial MB, Ronchi DI, Madeira K. Epidemiological profile of malignant neoplasms of the larynx in a laboratory of pathology in Criciúma - SC the period 2006 to 2010. Arq Catarin Med. 2011; 40: 64–68.

6. Chen M, Li C, Yang Y, Cheng L, Wu H. A morphological classification for vocal fold leukoplakia. Braz J Otorhinolaryngol. 2019; 85: 588-596.

7. Pietruszewska W, Morawska J, Rosiak O, Leduchowska A, Klimza H, Wierzbicka M. Vocal Fold Leukoplakia: Which of the Classifications of White Light and Narrow Band Imaging Most Accurately Predicts Laryngeal Cancer Transformation? Proposition for a Diagnostic Algorithm. Cancers. 2021;13 :3273.

8. Li DP, Chai W, Huang H.The diagnosis and treatment progress of vocal fold leukoplakia]. J of Clinical Otor.logy,. 2016 ;30 :838-840.

9. Kim CM, Chhetri DK.Triological Best Practice: When Is Surgical Intervention Indicated for Vocal Fold Leukoplakia?. Laryngoscope.2020; 130:1362-1363.

10. D’Avila JS, Santos RC, D’Avila DV. Métodos de avaliação em laringologia. In: Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial (Org.). Manuais de Otorrinolaringologia, 1st ed. São Paulo, Brazil: Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial; 2008:136–145.

11. Mendes Neto JA, Pinna BR, Caporrino Neto J, Pedroso JE. Comparison between telelaryngoscopy and suspension laryngoscopy in the diagnosis of benign vocal fold lesions. Braz J Otorhinolaryngol.2008; 74: 869–875.

12. Poels PJP, de Jong FICRS, Schutte HK. Consistency of the preoperative and intraoperative diagnosis of benign vocal fold lesions. J Voice. 2003; 17 :425–433