Haematology & OncologyPending review

Lymphoma

A malignant clonal proliferation of lymphocytes that expands within lymph nodes and lymphoid tissue rather than first flooding the marrow, so it presents as painless, progressive lymphadenopathy with cytokine-driven systemic 'B symptoms', behaving very differently depending on whether the clone is Hodgkin's Reed-Sternberg cells or a non-Hodgkin subtype.

In a nutshell

Lymphoma is a nodal, not marrow-first, malignancy, so it presents with painless lymphadenopathy rather than cytopenias. Cytokine release from the tumour causes B symptoms, which upstage the disease. Diagnosis always requires a tissue biopsy for architecture and immunohistochemistry.

Classic presentation

Painless, progressively enlarging cervical lymphadenopathy in a young adult, with or without fever, night sweats and weight loss.

Key points

  • Lymphoma starts as a nodal mass, unlike leukaemia which starts with marrow failure; this is why lymphadenopathy, not cytopenia, is the classic first sign.
  • B symptoms (fever, night sweats, weight loss) reflect cytokine release from the tumour and upgrade the clinical stage.
  • Hodgkin lymphoma is defined by Reed-Sternberg cells and spreads predictably and contiguously, generally carrying a good prognosis.
  • Non-Hodgkin lymphoma ranges from indolent to highly aggressive subtypes, and behaviour drives the urgency of treatment.
  • Diagnosis always requires an excision or core node biopsy. Fine-needle aspiration cannot provide the architecture needed to classify the lymphoma.

First-line investigation

Excision or core biopsy of the affected lymph node to obtain tissue architecture and immunohistochemistry for classification.

First-line management

Full Ann Arbor staging followed by subtype-specific combination chemotherapy, such as ABVD for Hodgkin lymphoma or R-CHOP for B-cell non-Hodgkin lymphoma.

Exam traps

  • Fine-needle aspiration is not sufficient to diagnose lymphoma: an excision or core biopsy is required for architecture.
  • Alcohol-induced lymph node pain is a classically quoted but uncommon feature of Hodgkin lymphoma. Do not rely on its absence to exclude the diagnosis.
  • B symptoms are a specific staging criterion (fever, drenching night sweats, unintentional weight loss) that changes management, rather than simply 'feeling unwell'.

Educational content pending clinical review. Not medical advice.