Acurácia das técnicas de Papanicolaou por citomorfologia e de Feulgen por citometria digital no diagnóstico de atipias em exames citopatológicos da mucosa oral

• Autor(a) principal: Futterleib, Alexandre
• Data de Publicação: 2007
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: Repositório Institucional PUCRS
• Texto Completo: http://hdl.handle.net/10923/377
• topic: ODONTOLOGIA; NEOPLASIAS BUCAIS; CITOPATOLOGIA

The aim of the present study was to compare the accuracy of the methods of Papanicolaou with cytomorphology and of Feulgen with digital cytometry in the detection of cellular atypias in cytopathologic examinations of the oral mucosa. The sample comprised 68 patients with lesions as indication for biopsy, and were distributed based on clinical diagnosis as follows: 25 squamous carcinomas, one erythroplakia, three fibromas, 23 fibroepithelial hyperplasias, 14 leukoplakias and nine cases of lichen planus. The lesions were submitted to exfoliative cytology by liquid-based system, and were immediately biopsied after collection of the cytologic specimen. The cytologic specimens were processed by the methods of Papanicolaou and of Feulgen, and the histopathologic specimens by the technique of paraffin embedding and staining with hematoxylin and eosin, which totaled 225 slides, 75 for each method. The slides processed by the Papanicolaou method were submitted to cytomorphologic analysis using a light microscope and classified as positive or negative for cellular atypia. In the Feulgen method, the analysis was carried out by digital cytometry, calculating the degree of DNA ploidy. The histopathologic specimens constituted the gold standard from which were calculated the indices of sensitivity, specificity, positive predictive value, negative predictive value and accuracy for the two cytopathologic methods. The Papanicolaou method had a sensitivity of 79. 4% and specificity of 92. 1%, while for the Feulgen these indices were respectively 96. 8% and 53. 1%. The indices of positive and negative predictive value were respectively 90% and 83. 3% for the Papanicolaou and 66. 7% and 94. 4% for the Feulgen. The accuracy was 86. 1% for the Papanicolaou and 74. 6% for the Feulgen. If the leukoplakias were excluded from the evaluation, the Papanicolaou method increased in sensitivity (96. 2%) without differing significantly for the Feulgen in this respect. If all the premalignant lesions were excluded from the evaluation, the two cytopathologic methods exhibited 100% sensitivity. The results allowed us to conclude the following. (1) The methods of Feulgen combined with digital cytometry and of Papanicolaou with cytomorphology exihibit a similar accuracy in the detection of atypias in cytopathologic examinations of the oral mucosa (p=0. 093). (2) the Papanicolaou method combined with cytomorphologic analysis has a positive predictive value (p=0. 023) and specificity (p<0. 001) superior to those for Feulgen, while the latter has greater sensitivity (p=0. 037). The methods did not differ significantly with regard to the negative predictive value (p=0. 251). (3) In the Feulgen method, the cytometric nuclear variables integrated optical density, area and diameter are capable of differentiating positive and negative lesions for atypia in cytopathologic examinations of the oral mucosa. (4) The difference in sensitivity and specificity suggests that the two cytopathologic methods should be applied in combination.