USCAP 2026 Annual Meeting – Long Course

Challenges and Controversies in Hematopathology: Classification Dilemmas in Search of Solutions

Modern hematopathology sits at the intersection of morphology, immunophenotyping, cytogenetics, and molecular genomics. As classification systems continue evolving and next-generation sequencing becomes increasingly integrated into routine diagnostics, pathologists are frequently confronted with cases that do not fit neatly into traditional diagnostic categories. The USCAP 2026 Long Course in Hematopathology addresses these realities directly through an advanced, case-based exploration of some of the most difficult classification dilemmas in contemporary hematopathology practice.

Released as part of the USCAP 2026 Annual Meeting educational program, this long course focuses on the practical integration of morphologic assessment, immunophenotypic interpretation, and molecular testing strategies to improve diagnostic precision in hematologic malignancies and related disorders.

This advanced educational package includes:

• Long Course Video Lectures
• Release Date: April 9, 2026
• Advanced Hematopathology Educational Content
• Case-Based Diagnostic Discussions

Rather than approaching hematopathology as a purely theoretical classification exercise, the course emphasizes the complex real-world diagnostic challenges encountered in both academic and community practice.

The Growing Complexity of Modern Hematopathology

Hematopathology has changed dramatically over the past decade. The rapid expansion of molecular diagnostics and genomic profiling has improved understanding of hematologic neoplasms but has also introduced increasing diagnostic complexity.

Today, diagnostic decision-making often requires simultaneous interpretation of:

• Histomorphology
• Flow cytometry
• Immunohistochemistry
• Cytogenetics
• Fluorescence in situ hybridization (FISH)
• Next-generation sequencing (NGS)
• Clinical presentation
• Disease evolution patterns

One recurring challenge involves cases with overlapping molecular and morphologic features that blur traditional diagnostic boundaries.

The course repeatedly emphasizes that classification systems continue evolving because disease biology itself is often more heterogeneous than rigid taxonomic categories suggest.

Integrating Molecular Diagnostics Into Routine Practice

A major focus of the program involves practical integration of genomic technologies into hematopathology workflows.

Topics include:

• Next-generation sequencing interpretation
• Molecular profiling strategies
• Genomic classification refinement
• Ancillary test selection
• Molecular-clinical correlation
• Cost-effective diagnostic workup design

The “Novel Genomic Technologies in Hematopathology” lecture provides a particularly useful framework for diagnostic pathologists navigating the expanding role of genomic testing in daily practice.

Importantly, the course does not present molecular testing as a replacement for morphology. Instead, it emphasizes how molecular data must be interpreted within the broader morphologic and clinical context.

Classification Challenges in Hematologic Neoplasia

One of the strongest aspects of the course is its focus on diagnostic ambiguity and classification controversy.

The sessions explore:

• Borderline hematologic entities
• Overlapping lymphoma categories
• Evolving WHO classification systems
• Diagnostic gray zones
• Rare neoplasms with heterogeneous features
• Clinically actionable subclassification strategies

In practice, hematopathologists frequently encounter cases where:

• Morphology is atypical
• Immunophenotypes are incomplete
• Molecular findings are nonspecific
• Disease categories overlap
• Classification systems remain in transition

The course appropriately acknowledges these realities while emphasizing structured diagnostic reasoning.

Histiocytic & Dendritic Neoplasms

The lecture on histiocytic and dendritic neoplasms reviews one of the more diagnostically challenging areas in hematopathology.

Topics include:

• Histiocytic proliferations
• Dendritic cell neoplasms
• Molecular alterations
• Differential diagnosis
• Immunophenotypic characterization

These entities are often difficult because of:

• Rarity
• Morphologic variability
• Overlap with inflammatory processes
• Limited standardized diagnostic frameworks

The session provides important updates regarding newer biologic and molecular insights that increasingly influence classification.

Pediatric Myelodysplastic Syndromes & Differential Diagnosis

Pediatric myelodysplastic syndromes represent another highly specialized and evolving area covered in the course.

The lecture examines:

• Pediatric MDS classification
• Bone marrow failure syndromes
• Germline predisposition disorders
• Differential diagnostic strategies
• Molecular abnormalities in pediatric disease

Pediatric hematopathology frequently requires different diagnostic considerations compared with adult disease because:

• Disease biology differs
• Germline syndromes are more relevant
• Morphologic interpretation may vary by age
• Classification criteria continue evolving

High-Grade B-Cell Lymphomas

The high-grade B-cell lymphoma session addresses one of the most clinically important and diagnostically complex lymphoma categories.

Topics include:

• Aggressive B-cell neoplasms
• Double-hit and triple-hit lymphomas
• Molecular subclassification
• Differential diagnosis
• Diagnostic algorithms
• Prognostic implications

Clinical decision-making becomes particularly important in these cases because diagnostic subclassification directly affects:

• Treatment intensity
• Prognostic assessment
• Eligibility for targeted therapies
• Clinical trial stratification

The course emphasizes practical diagnostic workflows for approaching aggressive B-cell proliferations.

Advances in Peripheral T-Cell Lymphomas

Peripheral T-cell lymphomas remain among the most heterogeneous and diagnostically difficult hematologic malignancies.

The lecture reviews:

• T-cell lymphoma classification updates
• Molecular profiling
• Immunophenotypic interpretation
• Differential diagnosis
• Emerging biologic insights

Many peripheral T-cell lymphomas demonstrate overlapping morphologic patterns, making integrated molecular and immunophenotypic assessment increasingly important.

Splenic B-Cell Lymphoma Classification

The splenic B-cell lymphoma lecture explores:

• Splenic marginal zone lymphoma
• Hairy cell leukemia variants
• Splenic diffuse red pulp lymphoma
• Classification refinements
• Diagnostic pitfalls

Splenic lymphoid neoplasms frequently present diagnostic difficulty because:

• Tissue sampling may be limited
• Morphology can overlap substantially
• Immunophenotypic profiles may not be entirely specific

The roadmap-style approach used in this lecture provides practical guidance for navigating these complex entities.

Case-Based Learning & Diagnostic Reasoning

A major educational strength of the course is its case-based structure.

The discussions repeatedly emphasize:

• Stepwise diagnostic reasoning
• Test selection strategy
• Morphologic interpretation
• Ancillary study integration
• Differential diagnosis development
• Clinical correlation

Case-based learning remains particularly valuable in hematopathology because real-world diagnostic practice rarely follows perfectly linear textbook patterns.

Practical Relevance for Modern Diagnostic Pathology

The course reflects the reality that hematopathologists today must increasingly function as integrative diagnosticians capable of synthesizing:

• Morphology
• Molecular pathology
• Clinical oncology
• Genomics
• Laboratory medicine

The educational focus remains grounded in practical application rather than purely academic classification theory.

What’s Included

• USCAP 2026 Long Course hematopathology lectures
• Advanced diagnostic pathology discussions
• Molecular hematopathology updates
• Case-based lymphoma and myeloid neoplasm reviews
• WHO classification and genomic integration topics
• Q&A educational section

Final Expert Perspective

Hematopathology continues evolving rapidly as molecular technologies reshape disease classification and deepen understanding of hematologic malignancies. Yet despite these advances, diagnostic uncertainty and classification controversy remain central challenges in daily practice.

The USCAP 2026 Long Course: Challenges and Controversies in Hematopathology provides a sophisticated and clinically grounded review of these evolving issues through expert-led discussions and practical diagnostic frameworks. For pathologists seeking deeper understanding of genomic integration, lymphoma classification, myeloid neoplasia, and complex hematopathology decision-making, this course offers a highly valuable educational resource aligned with the realities of modern diagnostic practice.