Our fusion annotation solution is built for routine somatic oncology workflows. Upload TSV or CSV files from widely used fusion callers across amplicon and hybrid capture assays, and review annotated fusion events in a structured format. RNA fusion analysis can be performed on its own or alongside DNA variants in single-sample or tumour-normal analysis.

Each reported fusion is standardized, linked to curated clinical evidence, and presented with visual and functional context to support clinical interpretation. Access to curated knowledgebases like OncoKB™, CKB, and COSMIC helps define molecular subtypes, inform prognosis, and guide therapy selection.

Supported Inputs

VarSome Clinical supports TSV and CSV files generated by commonly used RNA fusion detection pipelines, including:

• STAR-FusFusionCatcher
• Arriba
• Illumina DRAGEN RNA FusionFilter (TSO500)
• Illumina Bio-IT Platform
• Archer

You can continue to use your existing upstream workflow while VarSome Clinical standardizes the interpretation layer.

Structured Review in a Dedicated Fusion Table

All reported fusions are presented in a dedicated Fusions Table. For each fusion, you can:

• Review gene partners, breakpoint coordinates, and associated transcripts
• Inspect PFAM functional domains, when available
• Access consolidated biological and clinical relevance information
• View somatic annotations and classifications derived from curated oncology knowledgebases, such as OncoKB™ and CKB.

The table is designed for systematic case review, replacing fragmented file inspection with a consistent, evidence-linked framework. Choose from a list of filters or create filter sets to speed up routine analysis. Once you are ready, the information from the Fusion Table can be exported as an .xlsx file.

Visualization and Domain-level Context

When breakpoint information is available, fusion events can be visualized directly within VarSome Clinical. You can examine the structure of the rearrangement and the transcripts involved.

Structural and domain-level context are available within the same environment as clinical evidence, reducing the need to switch between tools.

Integrated Clinical Evidence

Fusion annotation integrates curated data and evidence from:

• OncoKB™

• CKB

• COSMIC

For each fusion, you can review information relevant to:

• Diagnostic classification
• Prognostics associations
• Therapeutic implications, including drug sensitivity and resistance, where available

This information is presented directly alongside the fusion event, saving you from manually consolidating evidence from multiple sources.

VarSome Clinical organizes and presents the evidence to support transparent, consistent interpretation, but the final classification and reporting decisions remain under your control.

Standalone RNA or Integrated DNA Plus RNA workflows

Fusion annotation can be performed as:

• A standalone RNA analysis from an RNA TSV or CSV file for somatic single-sample analysis
• An integrated somatic analysis combining RNA TSV or CSV data with DNA data

For integrated workflows, you can upload:

• DNA FASTQ plus RNA TSV or CSV for somatic single-sample and tumor-normal analysis
• DNA VCF or FASTQ plus RNA TSV or CSV for single sample analysis

In integrated cases, RNA fusions and DNA variants are reviewed within the same platform, supporting the interpretation of fusion events in the broader molecular context of the tumor.

Built for Clinical Oncology

Fusion events may be infrequent across tumor types, but their clinical impact can be substantial. They can define molecular subtypes, inform prognosis, and guide therapy selection. Consistent annotation is essential to ensure these events are interpreted correctly and documented clearly.

Fusion annotation in VarSome Clinical provides a structured, evidence-linked framework for reviewing RNA fusion events within your existing somatic workflow. It supports clarity, consistency, and defensible interpretation in routine clinical practice.

If you would like to see how our fusion annotation solution integrates with your workflow, contact sales@varsome.com to arrange a demo.