feat: cc4kv0.5.2 release notes

content/2.cc4k/1.index.md

@@ -6,6 +6,58 @@ navigation:
 
 CC4K (Cancer Classifications for Kids) provides a harmonized, computable pediatric cancer classification framework used across [St. Jude Cloud](https://stjude.cloud) and by the [CCDI Federated API](https://github.com/CBIIT/ccdi-federation-api).
 
+## v0.5.2
+
+Submitted: xxx, 2026
+
+Click [here](/files/cc4k/Official_CC4K_v0.5.2.xlsx){target="_blank"} to download.
+
+Version 0.5.2 delivers a restructuring update to the CC4K ontology, primarily within the Solid Tumor hierarchy, following pathologist recommendations and sample reclassifications.
+This release renames 6 classifications, repositions 8 nodes within the tree, removes 8 ambiguous nodes, and introduces 6 new disease nodes, with approximately 104 samples reclassified as a result.
+These changes correct classification inconsistencies and replace outdated or ambiguous terms to improve the accuracy of the tree.
+The following sections detail each of these changes:
+
+A. Renamed (6)
+
+- Follicular Thyroid Carcinoma — updated from Follicular Thyroid, NOS to reflect a more precise clinical classification.
+- Oncocytic Thyroid Carcinoma — replaces Hurthle Cell Thyroid Cancer, adopting current WHO terminology.
+- Poorly Differentiated Thyroid Carcinoma — updated from Poorly Differentiated Thyroid Tumor, adopting WHO accepted terminology.
+- Renal Cell Carcinoma, NOS — replaces Renal Cell Carcinoma to remove ambiguity, as RCC encompasses many distinct subtypes.
+- Infantile Hemangioma — replaces Infantile Hemangioendothelioma, a term no longer recommended, in favor of WHO accepted terminology.
+- Thymic Carcinoma — replaces Intrathyroidal Thymic Carcinoma, realigned with standard clinical terminology.
+
+B. Rearranged (8)
+
+The following nodes were misclassified and repositioned within the hierarchy following pathologist review and research validation.
+
+| Node                                                                                                                    | Previous Location                                                           | New Location                                                           |
+|-------------------------------------------------------------------------------------------------------------------------|-----------------------------------------------------------------------------|------------------------------------------------------------------------|
+| Juvenile Xanthogranuloma                                                                                                | Solid Tumor → Renal Tumors                                                  | Hematologic Malignancies → Other Hematologic Malignancies              |
+| Embryonal Sarcoma of the Liver                                                                                          | Solid Tumor → Undifferentiated Tumors                                       | Solid Tumor → Digestive System Tumors → Liver Tumors                   |
+| Spindle Cell Sarcoma, Spindle Cell Tumor, Undifferentiated Round Cell Sarcoma, and Undifferentiated Pleomorphic Sarcoma | Solid Tumor → Undifferentiated Tumors                                       | Solid Tumor → Soft Tissue Tumors → Tumors of Uncertain Differentiation |
+| Neurothekeoma                                                                                                           | Solid Tumor → Soft Tissue Tumors → Fibroblastic and Myofibroblastic Tumors | Solid Tumor → Skin Tumors                                             |
+| Signet Ring Cell Carcinoma                                                                                              | Solid Tumor → Genital Tumors                                                | Solid Tumor → Digestive System Tumors → Gastrointestinal Tumors        |
+
+**Table 1:** CC4K v0.5.2 Nodes Repositioned Within the Hierarchy.
+
+C. Deprecated (8)
+
+- Solid Cancer of Unknown Primary; Epithelioid Neoplasm, NOS; Metastatic Tumor, NOS; Mesenchymal Tumor, NOS; Myxoid Neoplasm, NOS; and Primitive Round Cell Neoplasm — removed as these classifications were deemed ambiguous and imprecise.
+Samples previously tagged to these nodes have been reassigned to Solid Tumor, NOS.
+- Thyroid Hyperplastic Nodule — removed as this is a subset of Thyroid Follicular Nodular Disease, under which its samples have been reassigned.
+- Myofibroblastic Sarcoma, NOS — removed as this is a subset of Myofibroblastic Neoplasm, NOS, under which its samples have been reassigned.
+
+D. New (6)
+
+This release adds six new disease classifications identified through curated case studies requiring formal classification within the tree: Ganglioneuroblastoma, Nodular; Renal Cell Carcinoma with MiT Translocations; Histiocytic Neoplasm, NOS; Hybrid Nerve Sheath Tumor; Adamantinoma; and Fibroepithelial Tumor.
+These nodes were informed by pathologist recommendations and ongoing case review, with samples previously assigned to broader classifications found to more accurately fit these newly introduced nodes.
+Their addition improves classification precision and maintains alignment with the WHO 5th Edition Classification of Tumors: Pediatric Tumors.
+
+A number of classifications were recommended for addition to the Solid Tumor tree but were deferred from this release as the current PeCan/Genomics Platform databases do not yet have sample representation for these nodes.
+Development releases, such as this one, prioritize structural accuracy and classification consistency for nodes already represented by samples.
+New nodes introduced primarily in alignment with the latest edition of WHO Pediatric Tumors are being evaluated for inclusion in upcoming releases.
+We welcome feedback on prioritization as we continue to expand the hierarchy.
+
 ## v0.5.1
 
 Submitted: April 14, 2026
@@ -16,7 +68,8 @@ Version 0.5.1 provides a focused incremental update to the CC4K solid tumor hier
 This release adds four new disease classifications identified through newly curated case studies requiring formal classification within the tree.
 These include the solid tumor entities Dyskeratosis Congenita, Chondromyxoid Fibroma, and Sinonasal Angiofibroma, as well as the hematologic malignancy Primary Mediastinal Large B-cell Lymphoma.
 
-These nodes are introduced to ensure accurate representation of incoming samples and to maintain alignment with the WHO 5th Edition Classification of Tumours: Paediatric Tumours (Pediatric bluebook). No structural reorganization of the tree was performed; rather, this update reflects a measured expansion within the existing Pediatric bluebook, preserving the chapter-based organizational principles established in v0.5.
+These nodes are introduced to ensure accurate representation of incoming samples and to maintain alignment with the WHO 5th Edition Classification of Tumours: Paediatric Tumours (Pediatric bluebook).
+No structural reorganization of the tree was performed; rather, this update reflects a measured expansion within the existing Pediatric bluebook, preserving the chapter-based organizational principles established in v0.5.
 
 ## v0.5
 
@@ -94,15 +147,17 @@ These were consolidated under a unified Genital Tumors node, with patient sex re
 
 Certain pediatric tumor entities span multiple anatomic sites, histogenic lineages, or fall outside the current scope of the WHO pediatric book.
 In CC4K v0.5, tubular adenoma, observed in the colon, gastrointestinal tract, and breast, was assigned a single canonical placement under Digestive System Tumors → Gastrointestinal → Tubular Adenoma.
-Breast cases (n=1) are classified as Adenoma, NOS with anatomic site captured via metadata, preventing duplication while preserving query flexibility. Canonical placements are periodically re-evaluated as sample volume and distribution evolve.
+Breast cases (n=1) are classified as Adenoma, NOS with anatomic site captured via metadata, preventing duplication while preserving query flexibility.
+Canonical placements are periodically re-evaluated as sample volume and distribution evolve.
 
 In total, 43 child leaf nodes in v0.5 fall outside the pediatric volume but were retained by evaluating where they might exist in a non-pediatric book.
 For example, adrenal cortical adenoma and carcinoma are not explicitly defined in the WHO pediatric book but appear across other WHO books which now belong under Endocrine Tumors → Adrenal Tumors.
 To see which nodes exist in non-pediatric books, we annotated this in column I in our downloadable tree for transparency.
 
 To address over-fragmentation, five low-frequency NEC nodes were consolidated into existing NOS categories.
 This decision was informed by experience with NEC/NOS usage in the CNS tumor tree and by review of WHO solid tumor classifications, which are largely not molecularly driven and do not consistently support NEC distinctions.
-Given the limited sample counts and lack of defining molecular features, maintaining separate NEC nodes was not justified. These categories were therefore consolidated, pending future evidence or novel biomarkers.
+Given the limited sample counts and lack of defining molecular features, maintaining separate NEC nodes was not justified.
+These categories were therefore consolidated, pending future evidence or novel biomarkers.
 
 Boundary conditions between the solid tumor (ST) and CNS trees were also clarified for germ cell tumors (GCTs).
 Tumors explicitly defined as brain-specific germ cell entities are now placed under the CNS tree (e.g., Germ Cell Tumor, Brain).