ANÁLISE DA MUTAÇÃO V600E DO GENE BRAF EM MELANOMAS CUTÂNEOS PRIMÁRIOS

Abstract

Melanoma comprises about 4% of skin cancers, however, more than 95% of stage IV melanoma patients will die within five years and most patients will succumb in a year. The most commonly mutated gene in melanoma is BRAF V600E mutation, described in 40-70% of cutaneous melanomas. This mutation results in the substitution of valine for glutamic acid in codon 600, resulting in the active form of the protein. The objective of this study was to investigate the frequency of BRAF V600E mutation in patients diagnosed with melanoma in Goiânia, as well as the possible associations between this mutation and clinical-pathological aspects of the cases analyzed. Seventy seven cases of melanoma from the Pathology Departament of Araújo Jorge Hospital, in Goiânia, Goiás were analized. Molecular analysis was performed by PCR and RFLP. Descriptive and comparative statistical analysis with Chi-square test were used in this study. The results demonstrated the presence of V600E mutation in 54 (70,1%) patients with cutaneous melanoma and no statistically significant association was found between the presence of mutation with other prognostics parameters such as age, gender, sun exposure, anatomic location, presence of metastasis, histological subtypes and histological parameters (Breslow thickness, presence of ulceration, signs of regression, lymphocytic infiltration and presence of satellites). Our results suggest that BRAF V600E mutation is a common event in melanomas and represents an important molecular target for therapeutic approaches in the treatment of this neoplasia.