IMMUNOHISTOCHEMISTRIAL AND HISTOPATOLOGICAL ASPECTS OF ASTROCYTOMAS IN THE REGION OF MARINGÁ (PR)

Introduction: Gliomas are the most common neoplasms of the Central Nervous System, representing 80% of the primary malignant tumors. Astrocytomas are 66% of the gliomas and have a global incidence 2,98/100.000 habitants. The immunohistochemistry associated with the histopathological analysis, are the main exams to the classification, according to World Health Organization. There is still a lot to discover about gliomas risk factors, ionizing radiation and use of cellular phones are the most studied of them; allergies are known as a protective factor. Farmers exposed to pesticides may be at risk, an excess incidence of gliomas has been noted on them, in several studies. Objectives: The aim of this study is to make a retrospective epidemiological analysis about the types of astrocytomas, studying the most important genes searched in immunohistochemistry, sex ratio, age of incidence, among other elements. Besides, establish a possible relation between the risk factors and the tumors found in the region of Maringá-PR. Methods: This research is a transversal, retrospective and descriptive study. 237 anatomopathological and 106 immunohistochemistry exams done between January of 2014 and December of 2018 were analyzed in 3 laboratories localized in Maringá-PR. There were included only tumors diagnosticated as astrocytomas in the period, resulting in 87 tumors with both exams. Results: Men are the most affected, representing 71,3% (62 patients), while women are 28,7% (25 patients). The medium age of the patients was 50,6 years (SD±20,4) in general, although the disease appears earlier in men, with 6,8 years of difference (48,7 against 55,5 years). Glioblastoma (grade IV), the most aggressive type of glioma, represents almost two thirds of the total number of astrocytomas (65,5%), followed by diffuse astrocytoma grade II (20,7%). One of the main markers of gliomas immunohistochemistry, IDH-1, was tested in 65 patients, showing a predominance of the wildtype gene (71,6%, 48 patients), which means a worse prognosis comparing to the mutant gene. Furthermore, other markers were included at the study, like GFAP, PS-100, p53, ATRX, OLIG2 and more. Conclusion: The data shows a higher incidence in men and the predominance of the glioblastomas, corroborating the literature. However, the number of cases is higher than the expected for the region, what might be related to the fact that Maringá is an area of high agricultural production and high use of pesticides.