What is hairy cell leukemia?

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What is hairy cell leukemia?

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Hairy cell leukemia is a very rare form of adult leukemia.

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Less than 2% of leukemias

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are reported as hairy cell leukemias.

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It's chronic or slow growing

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leukemia of the cells, blood cells called white cells.

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White blood cells.

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White blood cells are of different types.

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The specific type of white blood cell that's affected

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in hairy cell leukemia is a B lymphocyte.

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So it's a chronic leukemia of the B lymphocytes.

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Where does the name hairy cell leukemia come from?

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this is actually very, very familiar

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for medical students because it's a very important broad question for them.

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So when you look at the peripheral blood, the blood smear of patients

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with hairy cell under the microscope, these cells are these B lymphocytes.

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They look like regular B lymphocytes with size and shape,

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but they have like these hairy projections coming out of the surface.

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So that's where the name comes from.

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The hairy cells.

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What is the difference between hairy cell leukemia and CLL?

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So CLL and hairy cell leukemia are both chronic leukemias but

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they are different. They affect the same cell, the B lymphocyte.

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But they're different like causes are different presentations.

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So when you look at the cells,

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the kind of markers they express, that's how we differentiate between them

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which B cell they're both affect

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B cell, which B cell is a hairy cell, which B cell is a CLL cell.

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And these markers are on their surface

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and they're detected by what's called flow cytometry.

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For example, CLL cell is CD5 positive.

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Hairy cell leukemia is CD5 negative and CD10 negative.

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And it expresses specific markers like

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CD11 c, CD103, CD125, CD25.

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These markers are not expressed on CLL cells.