Cutaneous histiocytoses in children.

Area of Science:

• Dermatology
• Pathology
• Immunology

Background:

• Cutaneous histiocytoses are diverse skin diseases characterized by macrophage or dendritic cell accumulation.
• These conditions range from mild, self-resolving skin issues to severe, multi-organ diseases.
• Traditional classification relied on immunophenotypes, distinguishing Langerhans cell histiocytosis (LCH) from non-LCH.

Purpose of the Study:

• To review the evolving classification of cutaneous histiocytoses.
• To highlight the impact of recent molecular pathology findings.
• To emphasize the integration of molecular, clinical, and imaging data.

Main Methods:

• Review of recent pathophysiological and molecular findings in cutaneous histiocytoses.
• Analysis of updated classification criteria.
• Comparison of traditional and novel classification approaches.

Main Results:

• A shift in classification from immunophenotype to molecular alterations, clinical, and imaging characteristics.
• Identification of key molecular drivers in various histiocytoses.
• Recognition of juvenile xanthogranuloma and LCH as frequent pediatric entities.

Conclusions:

• The classification of cutaneous histiocytoses is increasingly based on molecular pathology.
• This new approach refines understanding and potentially improves patient management.
• Accurate classification is crucial for differentiating self-resolving from severe forms.