Case 12: AML with t(6;9)

This is AML w/ t(6;9). Can be a/w basophilia, but not always (couldn’t find in this case)

AML with t(6;9) is strongly associated with another genetic abnormality....

AML w/ t(6;9) is strongly associated with FLT3-ITD

FLT3-ITD can also be a/w other AML subtypes. Prognostic impact varies based on underlying cytogenetics:

• No impact on prognosis of AML w/ t(6;9) (already has poor prognosis) or t(15;17)
• Worse prognosis in AML w/ NPM1

FLT3 is a tyrosine kinase. Mutations occur in approximately 1/3 of patients with AML, often as internal tandem duplications (ITD) 👯‍♀️ These are in-frame duplications of 3 to >400 base pairs.

The next most common is a point mutation in D835

How can these be detected? 🤔

Fluorescent-labeled PCR-based assay ➡️ capillary electrophoresis to analyze fragment length

https://www.mayocliniclabs.com/test-catalog/overview/19739#Clinical-and-Interpretive

Why is this important?

In some subgroups of AML, ✨testing for FLT3 ITD in AML is important for prognosis (as stated above) & for guiding treatment (FLT3-targeted therapy)✨

See an excellent review here ⬇️:

https://pubmed.ncbi.nlm.nih.gov/29164965/

That’s all! Thanks for following along 🤗

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