4 DISCUSSION
According to our findings,
malignancy is associated with a single abnormal vascular pattern on the
surface of the vocal cords, whereas leukoplakia might be associated with
either normal or many abnormal vascular patterns. In addition, we
discovered that in patients with leukoplakia, the length of time spent
smoking (in years) had a detrimental impact on the surface and
vascularization of the voice cords. The number of cigarettes smoked each
day did not seem to make a difference.
Capillaries in the surface lamina
propria, smaller arteries and veins, as well as arterioles and venules
in the deeper layers, characterize the vascular microanatomy of human
vocal folds. Arterioles and venules have direct vascular
anastomoses.15
Under rigid laryngeal endoscopy, vocal cord leukoplakia presents as a
white or grayish confined patch, distributed granule, or verrucous
structure. It may have one or more localizations.10Leukoplakia is a chameleon-like epithelial transformation that can range
from benign thickening to malignant tumors. As a result, the name
”leukoplakia” is insufficient to characterize the lesion’s histological
identity.10-13
There are previous reports on a tissue-specific classification of
vascular changes associated with laryngeal leukoplakia. They finally
have found that age, non-homogenous lesion texture and existence of
hyperemia are independent predictors of
malignancy.14-16 Their results support the findings of
the present study to some extent because they also have found that age
and lesion texture may predict prognosis. However, these authors have
not further explored the impact of age on leukoplakia lesions. Our study
provides evidence that age may be
related to the development of this disease. Moreover, a further novelty
of the present study is that a very detailed study on the lesion texture
has been conducted. Leukoplakia lesions have traditionally been divided
into two categories from their appearances which were individually
homogenous and heterogeneous in many reports.17
Although new endoscopic tools, such as narrow band imaging, optical
coherence tomography and contact endoscopy have been developed to
improve the diagnosis of vocal fold leukoplakia, WL laryngoscopy is most
applied in clinical practice.18-21 The ability of
rigid or flexible laryngoscopy to visualize and characterize lesions of
vocal cords continues to improve.
Many researchers have reported high efficacy of CE in diagnosis of
mucosal lesions not only of larynx, but in other sites of head and neck
as well.10,12,23-25 These results have been obtained
taking the histopathological examination as the gold standard. However,
the technique of CE has definite advantages and limitations. Contact
endoscopy enables visualization of tumor margins, dysplasia, and normal
epithelium, thus offering the possibility of more precise complete
removal of laryngeal lesions in a single sitting. Along with in vivo
studies, contact endoscopy can also be used to analyze the excised
segment of the lesion and hence ensure whether the lesion has been
completely resected. The grade of dysplasia is indicated by the impaired
nucleus/cytoplasm ratio, nuclear hyperchromasia, and variation in the
number and appearance of the nucleoli. 21,23
Of course, there are limitations in the use of CE, which should be also
considered in the interpretation and validation of the results of the
present study. Two inherent
limitations are the inability to detect very early dysplasia and the
inability of differentiation of carcinoma in situ from invasive
carcinoma.