Spitz nevus and atypical spitzoid neoplasm.

Area of Science:

• Dermatopathology
• Oncology
• Melanocytic Neoplasms

Background:

• Spitz nevus (SN) and Spitzoid malignant melanoma (SMM) are distinct benign and malignant Spitzoid lesions.
• Atypical Spitzoid neoplasm (ASN) is an ambiguous category with overlapping features of SN and SMM.
• Accurate classification of ASNs is challenging due to poor interobserver agreement among dermatopathologists.

Purpose of the Study:

• To review current knowledge on Spitz nevus (SN) and atypical Spitzoid neoplasms (ASNs).
• To highlight diagnostic challenges and controversies in classifying Spitzoid lesions.
• To summarize advances in diagnostic modalities for these melanocytic neoplasms.

Main Methods:

• Review of histopathologic, clinical, and dermoscopic features of SN and ASNs.
• Examination of recent immunohistochemical and molecular diagnostic advancements.
• Discussion of controversies surrounding sentinel lymph node biopsy for ambiguous cases.

Main Results:

• Histologic examination is the current gold standard for diagnosing Spitzoid lesions.
• ASNs encompass a spectrum of lesions with unpredictable behavior, ranging from benign to metastatic.
• Despite improved accuracy, significant diagnostic challenges and interobserver variability persist.

Conclusions:

• Accurate differentiation of Spitzoid lesions, particularly ASNs, remains a significant challenge in dermatopathology.
• Further research into immunohistochemical and molecular markers is crucial for improved diagnostic accuracy.
• Clinical management decisions, including sentinel lymph node biopsy, require careful consideration for ambiguous melanocytic neoplasms.