Kronik Miyeloid Lösemili Bir Olguda Nadir Bir Varyant Translokasyonu (t(5; 9; 22) (q13; q34; q11.2))

Kronik miyeloid lösemi, kronik bir seyri takiben akut blastik dönüşüm görülen ciddi bir hematolojik hastalıktır. Özgün sitogenetik bulgusu t(9;22) veya orijinal ismi ile Philadelphia (Ph1) kromozomudur. Olguların çoğunda Ph1 saptanır. Ancak 9 ve 22. kromozomlar dışında başka bir üçüncü kromozomun translokasyona katılması halinde sitogenetik olarak Ph1 kromozomunun tipik görünümü oluşmaz ve gözden kaçabilir. Bu durumda konvansiyonel sitogenetik analizde saptanmayan anomali moleküler sitogenetik (FISH) analizle saptanabilir. Yazıda, Kronik Miyeloid Lösemili olguda Ph1 kromozomunu baskılayan varyant t(5;9;22) (q13; q34; q11.2) klonal anomalisi tanımlanmıştır.

A Rare Variant Translocation (t(5;9;22)(q13;q34;q11.2)) In A Case With Chronic Myeloid Leukemia

Chronic myeloid leukemia is a severe hematologic disorder with blastic transformation following a chronic phase. The specific cytogenetic findings of the disorder is t (9; 22) or Philadelphia (Ph1) chromosome. Ph1 is detected in most cases (95%). However, when a different chromosome other than 9 and 22 chromosomes are involved in translocation, the typical appearance of Ph1 chromosome does not occur and can be missed. In this case, the anomaly which is not detected in conventional cytogenetic analysis can be determined by molecular cytogenetics (FISH) analysis. In this paper we describe a unique clonal abnormality, t(5;9;22)(q13;q34;q11.2)- as a rare variant translocation in a case with chronic myeloid leukemia.

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