MPATH-Dx version 2.0 schema for melanocytic lesions: A robust tool for standardized diagnostic reporting

Area of Science:

• Dermatopathology
• Oncology
• Medical Diagnostics

Background:

• The previous MPATH-Dx version 1.0 schema for melanocytic lesions had five classes.
• This led to challenges in diagnostic agreement and patient management guidance.

Purpose of the Study:

• To introduce the revised MPATH-Dx (version 2.0) reporting schema.
• To improve diagnostic agreement and provide clearer patient management guidelines for melanocytic lesions.

Main Methods:

• Simplification of the classification hierarchy from five to four classes.
• Introduction of clearly defined histopathologic criteria for Class I and II lesions (low-grade and high-grade atypia).
• Inclusion of specific provisions for World Health Organization pathways to melanoma and intermediate tumors (melanocytomas).

Main Results:

• The new four-class hierarchy aims to enhance diagnostic agreement.
• Clearly defined criteria for low-grade (mild-to-moderate) and high-grade (moderate-to-severe) atypia are established.
• The schema now addresses less common melanoma pathways, melanocytomas, and a subset of very low-risk pT1a melanomas.

Conclusions:

• The MPATH-Dx version 2.0 provides a more streamlined and explicit approach to classifying melanocytic lesions.
• This revision is expected to improve diagnostic consistency and inform patient management strategies.
• The schema accommodates nuanced classifications, including intermediate tumors and early-stage melanomas with reassessment potential.