Morphological changes of the lip mucosa in chronic cheilitis

BACKGROUND: The vermilion border of the lips is exposed to external and internal factors that can induce inflammation. Tissue damage initiates a cascade of molecular processes that, under unfavorable conditions, may trigger oncogenesis.

AIM: The work aimed to assess morphological changes of the lip mucosa in chronic cheilitis.

METHODS: A retrospective morphological study was conducted on biopsy specimens of the lip mucosa from 46 patients aged 34 to 72 years (19 women and 27 men; mean age, 63.0 years) with chronic cheilitis: without epithelial dysplasia (n = 24) and with low- and high-grade dysplastic changes (n = 22). The following parameters were evaluated: epithelial layer alterations, severity of hyperplasia, cellular composition, degree of epithelial cell maturation, karyopyknotic index, characteristics of the inflammatory infiltrate, and vascularization of the lamina propria. Microscopic examination was performed with an Olympus CX-41 light microscope (Olympus, Japan) equipped with a digital camera. Using VideoTest-Morphology 5.2 software, 10 microscopic fields (objective, 40 mm; eyepiece, 10 mm) were analyzed for each specimen: vessel diameter, number, numerical density, and the ratio of stromal to angiomatous components were measured and recalculated per 1 μm² of area. Data were statistically processed with SPSS Statistics, version 22.0.

RESULTS: Elderly men predominated in both groups. A comparative analysis was performed of changes in the stratified squamous epithelium, inflammatory response, and vascularization of the lamina propria of the mucosa. In group B, the number of vessels per unit area was significantly higher than in group A. Microscopic features of reactive changes in the epithelium and lamina propria of the vermilion border were identified, predisposing to malignant transformation. In chronic cheilitis with epithelial dysplasia, an uneven arrangement of vascular loops was observed, with alternating areas of hypovascularized stroma and foci of increased vascularization of the lamina propria due to accumulation of small capillaries, which may serve as a morphological marker of poor prognosis.

CONCLUSION: In the differential diagnosis of lip diseases, pathologists, in addition to describing features of dysplasia of the stratified squamous epithelium, should note the character and severity of microcirculatory changes and inflammatory infiltration in the mucosa, while clinicians should take into account morphological data when choosing treatment strategies for patients.