Correlation of histopathological patterns in cutaneous melanoma with BRAF mutations

• Autor(a) principal: Jung,Juliana Elizabeth
• Data de Publicação: 2010
• Outros Autores: Matias,Jorge Eduardo Fouto, Blödorn-Schlicht,Norbert, Falk,Thomas M., Böer,Almut
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Jornal Brasileiro de Patologia e Medicina Laboratorial (Online)
• Texto Completo: http://old.scielo.br/scielo.php?script=sci_arttext&pid=S1676-24442010000600011
• topic: Malignant melanoma; Proto-oncogene proteins BRAF; Histolopathology

INTRODUCTION: Mutations on BRAF gene located on chromosome 7q are the most frequently found in cutaneous melanomas (60%-80%). The only study correlating histopathological patterns of cutaneous melanomas with the presence of BRAF mutations was undertaken by Viros et al. in 2008. The authors observed that morphological features of melanomas are associated with BRAF mutations. OBJECTIVES: To correlate histopathological patterns in cutaneous melanoma with the presence of BRAF mutations in order to corroborate the results of the study performed by Viros et al. METHODS: Paraffin embedded surgical specimens of 20 primary cutaneous melanomas with BRAF mutation and 20 specimens without BRAF mutation were evaluated independently by two dermatologists that carried out a blind experiment. The features analyzed were nesting, circumscription, presence of isolated melanocytes in the lesion, size and shape of neoplastic cells, and tumor cell pigmentation. RESULTS: "Nesting" was the most prevalent variable for the determination of melanomas with BRAF mutations according to both observers (r = 0.46; p = 0.04). CONCLUSION: As far as mutational status is concerned, it was not possible to confirm any predictive value for histopathological patterns such as circumscription, presence of isolated melanocytes in the lesion and cytological features. Difficulties in the interpretation of some histological criteria were demonstrated by the variation in the observers' conclusions. It is difficult to state if genetic alterations such as BRAF mutations may serve as biomarkers for melanoma classification.