ROS1 Fusion Angiomatoid Spitz Nevus With Eccrine Duct Fibroadenomatosis and Syringoid Features.

Area of Science:

• Dermatopathology
• Oncology
• Histology

Background:

• Eccrine duct fibroadenomatosis is a recognized reactive histological pattern.
• It is associated with various inflammatory and neoplastic conditions.
• Spitz nevi are melanocytic neoplasms with specific histological features.

Purpose of the Study:

• To report a unique case of a Spitz nevus with a ROS1 fusion.
• To describe associated histological findings, including eccrine duct changes.
• To contribute to the understanding of rare cutaneous neoplasms and their reactive phenomena.

Main Methods:

• Histopathological examination of a skin biopsy.
• Immunohistochemical staining for diagnostic markers.
• Molecular testing to identify genetic fusions (ROS1).

Main Results:

• Diagnosis of an angiomatoid Spitz nevus with a ROS1 fusion.
• Identification of associated eccrine duct fibroadenomatosis.
• Observation of acrosyringeal hyperplasia and syringoma-like ductal proliferation.

Conclusions:

• The case demonstrates an unusual co-occurrence of a ROS1-positive Spitz nevus and eccrine duct fibroadenomatosis.
• This finding expands the spectrum of reactive changes associated with Spitz nevi.
• Further research may elucidate the relationship between specific genetic alterations and reactive ductal proliferation.