Avaliação da concordância diagnóstica entre a citopatologia e a histopatologia do carcinoma de células escamosas de boca e análise histopatológica e da imunorreatividade ao anticorpo anti-ki-67 de margem

Abstract

The number of mouth cancer cases has increased significantly and squamous cell carcinoma is one of the most representative of all the malignancies that affect the mouth. The challenge is to make the diagnosis in early stages and is an important condition for effective treatment and the prognosis of patients. This research aimed to undertake two studies: 1) investigate the correlation between the cytopathologic and histopathologic diagnostic methods lesions in the mouth clinically suspected of squamous cell carcinoma and 2) examine the adjacent mucosa to squamous cell carcinoma of lip and tongue, by histopathology and immunoreactivity to anti-Ki-67. The sample consisted of: 1) smears of 132 patients who had clinically suspicious lesions of squamous cell carcinoma in mouth and were subsequently confirmed by histopathology, 2) retrospective study analyzed by histopathology and immunoreactivity to anti-Ki-67, 18 cases of patients who had, at least, one of the lateral surgical margins free of squamous cell carcinoma of lip and tongue. In study 1, after the cytopathological criteria establishment, all smears were evaluated by three independent examiners and classified as negative for malignancy, positive for epithelial dysplasia, suspicious for squamous cell carcinoma, positive for malignancy, positive for carcinoma and positive for squamous cells carcinoma. The comparative analysis between cytophatological and histopathological aspects (gold standard) showed diagnostic agreement of 83.3% with 95% confidence, estimated at between 76.9% and 89.7%. In the second study, the lateral mucosa immediately adjacent to squamous cell carcinoma was analised with the aim to identify architectural and cytological changes, as well as to graduate and compare two classification systems of epithelial dysplasia (World Health Organization and binary system proposed by Kujan) and to compare these areas with immunoreactivity to anti-ki-67. After analyses, it was observed that all mucosa samples presented dysplasia and showed variable architectural and cytological changes, suggesting association between the two grading systems, and that the location of immunolabeling of anti-Ki-67 above the basal layer is directly proportional to the severity of epithelial dysplasia in both studied systems. The inflammatory infiltrate in these margins was predominant in both anatomical sites, presenting in 57,1% of lip cases and 91% of tongue cases, with mononuclear pattern and lymphocytes predominance. The diffuse pattern of distribution (63,7%) was predominant in tongue, unlike in lip, where there was no predominance between patterns. The increase in rate of positive immunolabeling of anti-Ki-67 was directly proportional to the location of immunolabeling as well as the two systems of histopathological grading of epithelial dysplasia. The results of both studies indicate that cytopathology can be usually used as a routine diagnostic method of oral squamous cell carcinoma, and the evaluation of the anti-Ki-67 immunolabeling seems to be a good tool to investigate the architectural and cytological changes in adjacent margins of oral squamous cell carcinoma