Langerhan cell Histiocytoses

Question 1

Histiocytoses are a group of proliferative disorders that share a common ______ progenitor cell in bone marrow.

Answer 1

CD34+

Question 2

What are the different types of histiocytes?

Answer 2

• Langerhans cell
• Macrophages
• Dendritic cell

Question 3

Stains for langerhan cells?

Answer 3

CD1a

S100

Langerin (CD207)

Question 4

Stains for macrophages?

Answer 4

CD68

HAM56

Question 5

Age of onset for LCH?

Answer 5

1-4 years most commonly, but can be in adulthood as well

Question 6

What is the 3 year survival rate of LCH?

Answer 6

80%

Question 7

What are the poor prognostic factors with LCH?

Answer 7

• age younger than 2 years old
• multiorgan involvement
• organ dysfunction
• BRAF V600E mutation

Question 8

How are the LCH classified?

Answer 8

• based on number of organ systems involved:

- Single or multisystem involvement

Question 9

What organs can be involved with LCH?

Answer 9

literally all of them

Question 10

What are the high risk organs if affected in LCH?

Answer 10

spleen

bone marrow

liver

Question 11

Patients with LCH who have lesions of the _____have increased risk of CNS involvement.

Answer 11

Bones of skull

Question 12

What mutation is predictive of a poor prognosis in LCH?

Answer 12

BRAF V600E

Question 13

LCH often presents in the first year of life as a _______

Answer 13

diaper rash

Question 14

skin lesions of LCH typically present as:

Answer 14

subtle erythematous to brown scaly papules and plaques on the skin folds and scalp that can become more crusted/verrucous