Variants of melanoma

Area of Science:

• Dermatopathology
• Oncology
• Medical Classification Systems

Background:

• Current malignant melanoma classification includes superficial spreading, lentigo maligna, acral lentiginous, nodular, neurotropic, and desmoplastic types.
• Existing classifications have limited relevance to variant nevi, with exceptions like malignant cellular blue nevus and melanoma in giant congenital nevi.
• Melanoma classification based on size, with lesions ≤1 mm vertical dimension considered borderline melanocytic neoplasia, is also noted.

Purpose of the Study:

• To propose a novel classification for variant melanomas related to variant nevi.
• To introduce an alternative melanoma classification system based on nesting and cytological patterns in vertical growth.
• To refine melanoma categorization, particularly for "nevoid" melanomas and Spitz nevus-like lesions, using the concept of minimal deviation melanoma.

Main Methods:

• Review and analysis of existing melanoma classification systems.
• Development of a proposed classification linking variant melanomas to variant nevi.
• Formulation of an alternative classification based on microscopic growth patterns (nesting, cytology) in vertical growth phase.

Main Results:

• A proposed classification relating variant melanomas to variant nevi is presented.
• An alternative classification focusing on nesting and cytological patterns in vertical growth is introduced.
• These approaches aim to better categorize "nevoid" melanomas and Spitz nevus-like lesions.

Conclusions:

• Current melanoma classifications have limitations, especially concerning variant nevi.
• Proposed classifications offer improved categorization for specific melanoma subtypes.
• The concept of minimal deviation melanoma aids in refining these diagnostic tools.