HAEM5:Juvenile xanthogranuloma: Difference between revisions

* Juvenile Xanthogranuloma (JXG) is a clonal expansion of non–Langerhans cell histiocytes with dermal macrophage phenotype.

* Juvenile Xanthogranuloma is a rare histiocytic neoplasm comprising about 0.5% of all pediatric tumors, seldom seen in in adults. 20-35% cases are congenital, shows male predilection and mostly (>70% cases) arise during the first year of life.

* JXG are generally asymptomatic. Infants may present with ≥1 cutaneous, pale yellow-tan, dome-shaped papulonodular lesions, approximately5% patients show multiple lesions. These lesions begin as raised, pink to dark brown lesions that might get flatten later and heal/ scar within few months or years. A clinical subtype of JXG- benign cephalic histiocytosis occurs in head and neck of young children, asymptomatic, self-healing papular lesions. The lesions are often large, solitary and persistent in adults which needs exclusion of Erdheim–Chester disease. JXG may occur in patients with neurofibromatosis type 1, also reported in Wiskott–Aldrich syndrome.

* JXG involves and is generally confined to skin, head and neck, upper trunk and proximal extremities. Rarely ocular involvement, solitary lesion noted. Other extracutaneous sites of involvement- visceral, spinal, or intracranial area also reported rarely.  

Cutaneous JXGs: Early lesions are pink macules, later progress to form pale to tan, dome shaped lesions.

 

Visceral JXGs: Nodules with variable size and appearance.

Positive (universal) - CD68, CD163, CD4, CD14, factor XIIIa, and fascin

 

Positive (subset) - S100 (light nuclear and cytoplasmic staining)

 

Negative (universal) - CD1a and CD207 (langerin), ALK

 

Negative (subset) - N/A