Ph.D. Gruzdeva A.

State Establishment "Dnepropetrovsk Medical Academy 

Ministry of Health of Ukraine"

PERSPÅCTIVES AND POSSIBILITIES OF USE OF EXFOLIATIVE CYTOLOGY IN THE DIAGNOSIS OF LEUKOPLAKIA

OF THE ORAL MUCOSA

 

          Leukoplakia  is the mouth's reaction to chronic irritation of the mucous membranes of the mouth.

       Violation of maturation of the epithelium of the oral mucosa is the leading element of pathogenesis of  leukoplakia. Exfoliative cytology is a noninvasive procedure, which helped in identifying the cellular changes. The study revealed a subclinical phase of OHL, where the cellular changes were seen even before the appearance of the clinical lesion [2]

       The degree of maturity of the epithelium (maturation index) is determined by the balance of epithelial cells. In the epithelium of the mucous membranes of the mouth are allocated: basal, parabasal, intermediate and superficial cells, and in the stratum areas - horny scales.

       The basal cells can be in the smear with deep inflammation of the epithelium by its injury. The presence of parabasal cells shows sharply expressed atrophy. A sign of maturation of the epithelium is the predominance of intermediate cells in the smear. In not cornified sites of the oral mucosa to the maximum level of maturation of the epithelium corresponds the appearance of the surface cells, and in the cornified - horny scales.

       Maturation index (the ratio of parabasal / intermediate / surface / horny scales) assess the degree of differentiation of epithelial maturation completeness. As a normal for the not cornified epithelium is considered to be ratio 0 / 96 / 2,5 / 1,5; for cornified epithelium – 0 / 60 / 8 / 32 [6]. Oral exfoliative cytology has 100% specificity [3].

       Although it is considered a potentially malignant disorder the overall malignant progression of oral leukoplakia is of the order of 5% and even more. Nowadays there are no currently accepted markers to distinguish those that may progress to cancer from those that may not [5].

       Routine exfoliative cytology may be a reliable, noninvasive, and inexpensive technique for the diagnosis of hairy leukoplakia [1]. Oral exfoliative cytology has 100% specificity [3].

      The aim of our study was to determine the degree of maturity of the epithelium of the oral mucosa in different forms of leukoplakia.

       Materials and methods. We conducted a clinical and laboratory study of 58 patients with leukoplakia of the oral mucosa. In our study we used the classification of the oral mucosa by Danilevsky N. F., Urbanowich L. I., 1979. The flat form of  leukoplakia was diagnosed in 34 patients (58.62%), rising leukoplakia - in 16 (27.58%), verrucous leukoplakia - in 5 (8.26%) and erosive form - in 3 (5.17%) .

       For the manufacture of the cytological preparations the fence of the lesion was performed in several ways: direct imprint, impression smears or scraping. Preparations were fixed in a mixture of Nikiforov. Coloring was performed by Papanikolau. In smears we had examined the ratio of epithelial cells.

       Results and its discussion. In patients with flat form of  leukoplakia among the epithelial cells in the smear prevailed horny scales (51,5%) and superficial cells (31%). The content of intermediate cells was reduced to 17.5%. All this can be interpreted as a violation of the maturation of the epithelium, as hyperkeratosis and chronic inflammation.

       In patients with rising leukoplakia the breach of epithelial differentiation was aggravated: the ratio of parabasal / intermediate / surface / horny scales was 0/25/29/46.

      The analysis of the results of cytological research of patients with warty leukoplakia revealed a severely impaired maturation of the epithelium – so named “left shift”. In this case, in a smear appeared basal (3%) and parabasal (10,5%) cells, were observed phenomena of dyskaryosis, that is reflecting the increasing damaging effect on the oral mucosa.

       The results of cytological research in patients with erosive form of leukoplakia are typical for a significant injury of the epithelium and for the defeat of it with a deep inflammation. In compare with warty form of leukoplakia in smears were found the increasing of basal (4%) and parabasal cells (15,5%).

      So, the degree of maturity of the epithelium decreases with worsening of the forms of leukoplakia. Determining of the degree of differentiation of epithelium of the oral mucosa with the use of exfoliative cytology method is the auxiliary diagnostic test for the diagnosis of "leukoplakia" and can be used in combination with other methods of research. The method of exfoliative cytology is characterized by simplicity, security, rapidity of obtaining of results and plays an important role in the diagnosis of different forms of leukoplakia.

 

REFERENCES

1.     Migliorati CA, Jones AC, Baughman PA. Use of exfoliative cytology in the diagnosis of oral hairy leukoplakia . J Oral Surg Oral Med Oral Pathol.1993 Dec;76(6):704-10

2.     Ajay Reginald and B. Sivapathasundharam. Oral hairy leukoplakia: An exfoliative cytology study. J Contemp Clin Dent. 2010 Jan-Mar; 1(1): 10–13.

3.     Sathish Kumar, N. Vezhavendhan, Priya S. Role of Oral Exfoliative Cytology in Oral Leukoplakia and Squamous cell Carcinoma. International Journal of Clinical Dental Science, Vol 2, No 1 (2011)

4.     Ajay Reginald and B. Sivapathasundharam. Oral hairy leukoplakia: An exfoliative cytology study.  Contemp Clin Dent. 2010 Jan-Mar; 1(1): 10–13.

5.     Parlatescu I, Gheorghe C, Coculescu E, et al.  Oral leukoplakia - an update. [Journal Article]. Maedica (Buchar) 2014 Mar; 9(1):88-93.

6.     Áûêîâ Â.Ë. Ãèñòîëîãèÿ è ýìáðèîëîãèÿ îðãàíîâ ïîëîñòè ðòà ÷åëîâåêà. – Ñ.Ïåòåðáóðã, “Ñïåöèàëüíàÿ ëèòåðàòóðà”, 1996. – 247 ñ.