Analysis of BRAF V600E Mutation in Gastrointestinal Malignant Melanomas

INTRODUCTION: We aimed to investigate BRAF V600E mutation in gastrointestinal mucosal melanomas and patients’ clinical outcomes.
METHODS: The melanomas which were diagnosed at Ankara Yýldýrým Beyazýt University/ Atatürk Education and Research Hospital between 2006 and 2015 were retrospectively screened for mucosal melanomas. Gastrointestinal malignant melanomas were obtained from these cases. BRAF V600E mutation analysis is performed to a total of 6 gastrointestinal melanoma cases by real time PCR method. In addition clinical characteristics of these cases have beeen reviewed.
RESULTS: Six of the 14 patients with mucosal melanoma were gastrointestinal. There were cases of rectum and 2 cases of small bowel, and patients were between 54- 84 years. BRAF V600E mutation was detected in one of the small bowel localized case with omentum metastasis.
DISCUSSION AND CONCLUSION: The only case with BRAF V600E mutation was multifocal therefore mucosal metastatis is considered in this case. Primary cutaneous and ocular melanomas can frequently metastasize to the gastrointestinal tract. However, it may not always be possible to identify the primary tumor. Primary gastrointestinal melanomas are very rare and genetically different from cutanous melanomas.

Gastrointestinal Malign Melanomlarda BRAF V600E Mutasyon Analizi

GÝRÝÞ ve AMAÇ: Gastrointestinal mukozal malign melanomlarda BRAFV600E mutasyon varlýðý ve olgularýn klinik özelliklerini incelemeyi amaçladýk.
YÖNTEM ve GEREÇLER: Ankara Yýldýrým Beyazýt Üniversitesi Atatürk Eðitim ve Araþtýrma Hastanesi Patoloji bölümünde 2006-2015 yýllarý arasýnda taný almýþ malign melanomlar retrospektif olarak taranarak mukozal melanomlar ve bunlar içerisinden gastrointestinal malign melanom olgularý elde edilmiþ ve arþiv bloklarýndan hazýrlanan kesitlerde gerçek zamanlý PCR yöntemi ile BRAFV600E mutasyonu araþtýrýlmýþtýr. Ayný zamanda bu olgularýn klinik özellikler gözden geçirilmiþtir.
BULGULAR: Mukozal Malign Melanom tanýsý alan 14 olgunun 6’sý gastrointestinal yerleþimli idi. Bu olgular 54-84 yaþ aralýðýnda olup tümör 4’ü rektum, 2’si ince barsak lokalizasyona sahipti. Olgularýn tamamýnda PCR yöntemi ile çalýþýlan BRAF-V600E mutasyonu yalnýzca ince barsak yerleþimli ve omentum metastazý olan 1 olguda izlenmiþtir.
TARTIÞMA ve SONUÇ: BRAF-V600E mutasyonu var olan tek olguda tümör multi odaklar halinde geliþim göstermiþ olup bu nedenle mukozal metastaz düþünülmüþtür. Primer kutanöz ve oküler melanomlar gastrointestinal sisteme sýk olarak metastaz yapabilmektedir. Ancak primer odaðý saptamak her zaman mümkün olmayabilir. Primer gastrointestinal melanomlar da çok nadir olup genetik açýdan da kutanöz melanomlardan farklý özellikler içerebilir.