71 Inflammatory and Malignant Histiocytosis Flashcards
(107 cards)
Archaic term for tissue macrophages
Histiocyte
Dendritic Cell-related Histocytic disorders
Langerhans cell histiocytosis
Juvenile xanthogranuloma/Erdheim-Chester disease
Macrophage-Related Histiocytic Disorders
Hemophagocytic syndromes
Primary hemophagocytic lymphohistiocytosis
Secondary hemophagocytic syndromes
Rosai-Dorfman disease
Malignant Histiocytic Disorders
Monocyte-related leukemias
Extramedullary monocytic tumor (myeloid sarcoma)
Macrophage-related histiocytic sarcoma
Dendritic cell malignancy (malignant histiocytosis)
What mutations separate inflammatory neoplasias from hemophagocytic lymphohistiocytosis (HLH)
Recurrent mitogen-activated protein kinase (MAPK) pathway mutations
Hemophagocytic lymphohistiocytosis (HLH) is characterized by (monoconal or polyclonal) reactive macrophages
Polyclonal
Classification of histiocytic disorders based on clinical, histologic, and molecular features:
L group:
C group:
R Group:
M group:
H group:
L group: Langerhans cell histiocytosis, indeterminate cell histiocytosis, and Erdheim-Chester disease
C group: Juvenile xanthogranuloma
R Group: Rosai-Dorfman Disease
M group: Malignant histiocytic diseases
H group: Hemophagocytic lymphohistiocytic diseases
Pathologic cluster designation of Langerhans cell histiocytosis
CD1a + /CD207 + DCs with rounded morphology
Its DC has abundant eosinophilic to amphophilic cytoplasm, and a nucleus that is kidney-shaped, deeply indented, or grooved (eg, reniform)
Langerhans cell histiocytosis
Recurrent mutations in MAPK pathway genes have been identified in more than____% of LCH lesions with BRAF V600E in over ____% of cases
80%
50%
BRAF V600E mutation can be detected by
Immunostain (VE1 antibody)
Polymerase chain reaction (PCR)
A type II transmembrane protein located on the cell surface of epidermal LC and is associated with formation of characteristic intracytoplasmic Birbeck granules
Langerin (CD207)
Immunophenotype of RDD
CD68 + /CD163 +
Characteristic finding in RDD
Emperipolesis (viable lymphocytes trafficking through cytoplasm)
Immunophenotype of JXG and ECD
CD68 + /CD163 + /Factor XIIIa + /CD1a – DCs
Characteristic finding in JXG and ECD
Abundant vacuoles that are described as foamy or lipid laden and stained with fascin
TRUE OR FALSE
Hemophagocytosis is characteristic and a required specific feature of HLH.
FALSE
Hemophagocytosis is characteristic, but neither a required nor specific feature of HLH.
Disease described in children with combinations of lytic bone lesions, skin and mucosal lesions, and diabetes insipidus
Hand-Christian-Schüller disease
Disease presentation in children as histiocytic infiltration of marrow, spleen, liver, and lung
Letterer-Siwe disease
Gene involved with Hispanic populations that was associated with increased risk of developing LCH
SMAD6
The only proven exposure increasing the risk of LCH, specifically in adults with pulmonary LCH
Cigarette smoking
Mutation in LCH associated with an increased risk of treatment failure and LCH-associated neurodegeneration.
BRAF V600E
The cell of origin of LCH
Epidermal LC
The most frequent presenting signs of LCH
Skin rashes and bone lesions