PeCan Release Notes

Welcome to the PeCan Release Notes page. Here, you'll find a running log of new features, improvements, and changes we've made to PeCan—along with a bit of the rationale behind why we're making them. Check back after each release to see what's new! If you have any questions, feel free to reach out to us at support@stjude.cloud.

September 2026

Cohort Building

This release introduces cohort building to PeCan, giving you a way to build custom cohorts from over 12,000 pediatric cancer samples. You can dynamically build and stratify cohorts, then explore them across Oncoprint, Histology, and Gene Expression.

New Features

• Cohort Creation Workflow: Explore samples using the subtype tree or search to create a cohort from all samples within a diagnosis subtype. You can also build a cohort by exploring the full sample set, either from the Cohort page or from within a supported data facet.
• Lens: Single Cohort: View the samples in a custom cohort and explore the visualizations and associated data available in PeCan. Cohort Comparison: Compare two custom cohorts side by side.
• Cohort Summary Page: Create and curate your cohorts while viewing associated metadata and data facet availability for the sample set.
• Cohort Views in Oncoprint, Histology and Gene Expression: Bring a custom cohort into Oncoprint, Histology, or Gene Expression to explore that facet's visualizations and data scoped to just your cohort's samples, rather than the full PeCan dataset.

This is the first release of a broader set of cohort-building features St. Jude Cloud will be rolling out. We plan to continue expanding cohort support across the application, including St. Jude Cloud curated cohorts, cohort views in Variant Prevalence and Mutational Signatures, and more. Please share any feedback or questions with support@stjude.cloud

June 2026

This release updates Oncoprint to align visually with the rest of PeCan and adds new features for exploring mutation data by diagnosis subtype.

Oncoprint

• Visual Alignment: Mutation colors now match the Variant Prevalence data facet, making it easier to recognize mutation types across views.
• Row Configuration: Rows in the Oncoprint can be reordered by drag-and-drop, or sorted and filtered.
• Navigator Panel: A new panel at the bottom of the view supports navigation across larger cohorts of samples.

Variants

• Variant Prevalence: Mutational prevalence summaries are now available for higher-level subtype nodes such as Hematological Malignancy, Lymphoid Neoplasm, and Myeloid Neoplasm. At higher-level subtype nodes, the pathway prevalence summary is segmented by immediate child diseases. At lower-level disease nodes, pathway prevalence is segmented by all descendant leaf subtypes.

ProteinPaint & GenomePaint

• Both tools now default to hg38.

May 2026

This release introduces our Subtype Tree to PeCan, a new way to explore and navigate the full CC4K hierarchy of pediatric cancer diagnoses across St. Jude Cloud data.

New Features

• Subtype Tree: Built on the CC4K framework, the Subtype Tree provides a navigable, hierarchical view of pediatric cancer diagnoses organized under three root categories: Hematopoietic Malignancies, Brain Tumor, and Solid Tumor. Users can expand any node to explore subtypes, with sample counts displayed at each level to show data availability.
• Node Tooltip: Each node includes a tooltip that provides additional details and quick navigation to each data facet for the available data.
• Download Options: The Subtype Tree can be downloaded as an SVG, and a link to download all PeCan metadata is available from the Subtype Tree view.

February 2026

This release brings a major set of user interface changes to PeCan, including redesigned navigation, integrated help guides, and updated keyboard controls. Watch the video below or read on for a full breakdown of what's changing and why.

New Features

• Redesigned Navigation: New left-side navigation panel for easy navigation between data facets and access to the Diagnosis Search. This redesign lays the groundwork for a new cohort building feature that we expect to land later this year—stay tuned!
• Help Guides: Navigation to our PeCan Help Guide documentation is now accessible on the new left-side navigation panel. We intend to continue contributing heavily to PeCan's help guides in the months and years to come.
• Keyboard Controls: Updated keyboard controls to quickly access PeCan's Diagnosis Search. Our goal is to continue sharpening the experience of using PeCan seamlessly for frequent visitors.

Improvements

• Accompanying all of the user interface changes, we've updated the position of the Diagnosis Search on the PeCan Homepage to better fit in with the new position of the navbar.

We welcome feedback on these changes! Anyone is welcome to reach out to us at support@stjude.cloud or via the chat bubble integrated on the site.