Novel and emerging cutaneous soft tissue tumours

Area of Science:

• Dermatopathology
• Molecular Pathology
• Oncology

Background:

• Molecular advancements have broadened the understanding of cutaneous soft tissue tumors.
• Several novel entities with specific genetic drivers have been identified.

Purpose of the Study:

• To review and outline the key features of recently described cutaneous soft tissue tumors.
• To aid in the accurate recognition and classification of these emerging neoplasms in dermatopathology practice.

Main Methods:

• Histopathological analysis
• Immunophenotypic characterization
• Molecular feature assessment
• Literature review of emerging tumor entities

Main Results:

• Detailed description of hybrid superficial ALK-rearranged myxoid spindle cell neoplasm/epithelioid fibrous histiocytoma.
• Outline of superficial neurocristic tumour characteristics.
• Review of ALK-rearranged epithelioid vascular neoplasm features.
• Summary of MITF pathway-activated melanocytic tumour findings.

Conclusions:

• Accurate diagnosis requires integrating histopathological, immunophenotypic, and molecular data.
• Understanding morphological overlaps and current knowledge gaps is crucial.
• This review facilitates the classification of emerging cutaneous soft tissue tumors.