PA19.1-6 | Lymphomas — Hodgkin vs Non-Hodgkin — Summary & Reflection

REFLECT

Return to the opening case: 22-year-old woman, right supraclavicular rubbery node, B symptoms, near-normal CBC.

With what you now know:
1. Which single HL subtype fits her age, sex, and mediastinal location?
2. The biopsy shows collagen bands dividing the node into nodules, with large cells in lacunar spaces. What subtype is confirmed?
3. Her staging CT shows mediastinal and right neck nodes only — no disease below the diaphragm, no bone marrow involvement. What Ann Arbor stage (with suffix) does she have?
4. If she had presented instead with a rapidly growing abdominal mass, EBV positivity in nearly all tumour cells, and a jaw lesion, what diagnosis would you consider and what chromosomal translocation would you expect?

Write your answers before checking — this is the self-test pattern for OSPE scenarios.

KEY TAKEAWAYS

Lymphomas: Key Consolidation Points

Hodgkin Lymphoma
• Defined by Reed-Sternberg cell: CD15+, CD30+, CD45−, B-cell origin
• Four classical subtypes: Nodular Sclerosis (commonest, young women), Mixed Cellularity (EBV 70%), Lymphocyte-Rich, Lymphocyte-Depleted
• NLPHL: LP/popcorn cell, CD20+, indolent
• Contiguous orderly spread; Ann Arbor staging with A/B suffix
• B symptoms: fever, night sweats, >10% weight loss

Non-Hodgkin Lymphoma
• B-cell (85%) or T/NK-cell (15%); no RS cell
• Indolent: Follicular (t(14;18)/BCL2, back-to-back follicles, BCL2+ within follicles), SLL
• Aggressive: DLBCL (commonest NHL), Burkitt (t(8;14)/MYC, starry-sky, Ki-67~100%)
• Non-contiguous spread; extranodal common; leukaemic overlap in indolent types

Pathogenesis
• Translocations: BCL2 (FL), MYC (Burkitt), Cyclin D1 (mantle cell)
• EBV: endemic Burkitt, MCHL/LDHL, post-transplant lymphoproliferative disorder
• Immunodeficiency: removes surveillance → EBV-driven NHLs

Diagnosis
• Excision biopsy mandatory (architecture + IHC + cytogenetics)
• IHC: CD15/CD30 for HL; CD20/CD10/BCL2/Ki-67 panel for NHL subtyping

Cross-links
• H7: CLL ↔ SLL (same clone, blood vs node); reactive vs neoplastic lymphadenopathy
• H11: Myeloma = post-GC plasma cell neoplasm, separate category