What is the initial workup for a suspected new lymphoproliferative disease?

Initial Workup for Suspected New Lymphoproliferative Disease

The initial workup for suspected lymphoproliferative disease should include a comprehensive histological examination from an excisional lymph node biopsy, complete blood count with differential, blood chemistry including LDH, CT scans of neck/chest/abdomen/pelvis, and bone marrow aspiration and biopsy. 1, 2

Diagnostic Tissue Sampling

• Excisional lymph node biopsy: Essential for accurate diagnosis
  • Core biopsies only for inaccessible nodes (e.g., retroperitoneal)
  • Fine-needle aspiration is inappropriate and insufficient 1
• Fresh frozen tissue: Should be stored when possible for additional molecular analyses 1, 2
• Histopathological assessment: Must include:
  • WHO classification
  • Immunohistochemistry (including CD30 for certain lymphomas)
  • Ki-67 proliferation index 1

Laboratory Investigations

• Complete blood count with differential 1, 2
• Blood chemistry panel:
  • Lactate dehydrogenase (LDH)
  • Uric acid
  • Comprehensive metabolic panel 1, 2
• Additional testing:
  • Serology for HIV, hepatitis B and C 1
  • Serology for HTLV-1/2 in endemic areas 1
  • β2-microglobulin (particularly for follicular and mantle cell lymphomas) 1
  • Disseminated intravascular coagulation panel (PT, PTT, fibrinogen, D-dimer) 1, 2
  • Assessment for tumor lysis syndrome in high-risk patients 1

Imaging Studies

• CT scan of neck, chest, abdomen, and pelvis: Required for all patients 1
• PET-CT:
  • Recommended for certain lymphoma subtypes (particularly aggressive ones)
  • Optional for indolent lymphomas
  • Particularly useful to confirm localized stage I/II disease 1, 2
• Additional imaging:
  • Brain MRI if neurological symptoms are present
  • Chest X-ray or ultrasound may be appropriate in select cases 1, 2

Bone Marrow Assessment

• Bone marrow aspiration and biopsy: Essential component of staging 1
• Cytogenetic analysis: Required for proper classification 1, 2
• Immunophenotyping: Multiparametric flow cytometry (minimum 3-4 colors) 2
• Molecular studies: For detection of specific genetic abnormalities 1, 2

Additional Specialized Evaluations

• Lumbar puncture: For patients with:
  • Aggressive subtypes (e.g., blastic variant of mantle cell lymphoma)
  • Central nervous system symptoms
  • High-risk features (blastoid variant, elevated LDH, poor performance status) 1
• Gastrointestinal evaluation:
  • Upper and lower endoscopy with biopsies for suspected GI involvement
  • Particularly important in mantle cell lymphoma (15-30% have GI involvement) 1
• Testicular examination: Especially important in T-cell ALL 1

Common Pitfalls to Avoid

• Inadequate tissue sampling (core biopsies or FNA instead of excisional biopsy)
• Failure to store fresh tissue for molecular studies
• Incomplete immunophenotyping
• Overlooking extranodal disease sites
• Inadequate molecular profiling for risk stratification 2

By following this systematic approach to the workup of suspected lymphoproliferative disease, clinicians can ensure accurate diagnosis, appropriate staging, and optimal treatment planning for these complex disorders.