Clinical, morphologic, and genomic findings in ROS1 fusion Spitz neoplasms
Pedram Gerami1,2, Daniel Kim3, Elsy V Compres3
1Department of Dermatology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA. pedram.gerami@nm.org.
Summary
This study details ROS1 fusion Spitz neoplasms, finding they often present with characteristic microscopic features and appear to be indolent tumors with no recurrences or metastasis observed in this series.
Area of Science:
- Dermatopathology
- Genomic Medicine
- Oncology
Background:
- Spitz neoplasms are defined by specific genomic fusions.
- Accurate diagnosis and understanding clinical behavior are crucial for Spitz neoplasms.
- ROS1 fusions represent a distinct subtype requiring detailed characterization.
Purpose of the Study:
- To present the largest series of ROS1 fusion Spitz neoplasms to date.
- To analyze the clinical, morphologic, and genomic features of these tumors.
- To compare morphologic features with non-ROS1 Spitz neoplasms to identify diagnostic markers.
Main Methods:
- Retrospective analysis of 17 ROS1 fusion Spitz neoplasms.
- Morphologic comparison with 99 non-ROS1 Spitz neoplasms.
- Genomic analysis to identify ROS1 fusion partners.
Main Results:
- Ten Spitz nevi and seven Spitz tumors were identified; none were Spitz melanoma.
- ROS1 fusion tumors showed characteristic features like plaque-like/nodular silhouette and spindle cell morphology.
- PWWP2A and TPM3 were common ROS1 binding partners; no recurrences or metastases were observed.
Conclusions:
- Most ROS1 fusion Spitz neoplasms exhibit typical microscopic features.
- Some cases may show overlapping features with other genomic subtypes.
- Preliminary data suggest these neoplasms are indolent with low-grade behavior.
