What is the next step in management for a 57-year-old female with a surgically excised gluteal region lump diagnosed as diffuse large B-cell lymphoma (DLBCL) with no other symptoms?

Management of Diffuse Large B-Cell Lymphoma After Excisional Biopsy

The next step in management for a 57-year-old female with a surgically excised gluteal region lump diagnosed as diffuse large B-cell lymphoma (DLBCL) with no other symptoms is to perform a complete staging workup including FDG-PET/CT scan, laboratory tests, and bone marrow biopsy to determine the extent of disease before initiating R-CHOP chemotherapy.

Comprehensive Staging Workup

A thorough staging evaluation is essential before treatment decisions can be made, including:

Imaging Studies

• FDG-PET/CT scan - Gold standard for staging DLBCL patients 1
  • More accurate than contrast-enhanced CT alone
  • Can detect nodal and extranodal involvement
  • May obviate the need for bone marrow biopsy if it shows bone/marrow involvement

Laboratory Tests

• Complete blood count
• Routine blood chemistry including:
  • Lactate dehydrogenase (LDH)
  • Uric acid
• Screening tests for:
  • HIV
  • Hepatitis B (HBs antigen, anti-HBs and anti-HBc antibodies)
  • Hepatitis C
• Protein electrophoresis 1

Bone Marrow Assessment

• Bone marrow aspirate and biopsy
  • May be avoided if PET/CT clearly demonstrates bone/marrow involvement 1
  • PET/CT has a high negative predictive value (98%) for bone marrow involvement 2

Cardiac Function Assessment

• Left ventricular ejection fraction evaluation before treatment 1

Additional Considerations

• Diagnostic lumbar puncture in high-risk patients:
  • Elevated LDH

  • 1 extranodal site

  • Involvement of specific sites (testes, breast, paranasal sinuses) 1

Risk Assessment

After staging is complete:

• Determine Ann Arbor stage (I-IV) 1
• Calculate International Prognostic Index (IPI) and age-adjusted IPI (aa-IPI) 1
  • These scores guide treatment decisions and predict outcomes

Treatment Planning

Once staging is complete, treatment should be initiated promptly:

Standard Treatment Approach

• R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, prednisone) is the standard treatment 3
  • Number of cycles (6-8) will depend on stage and risk factors
  • Treatment offers 60-70% chance of cure 4

Treatment by Risk Category

• For low-intermediate risk (aaIPI=1) or low risk (aaIPI=0) with bulky disease:

  • R-CHOP × 6 cycles with radiotherapy to sites of previous bulky disease, OR
  • R-ACVBP followed by sequential consolidation 1

• For high and high-intermediate risk (aaIPI ≥2):

  • R-CHOP × 6-8 cycles with 8 doses of rituximab 1

Important Considerations

Potential Pitfalls

• Delay in staging workup: Prompt and complete staging is essential for appropriate treatment planning
• Incomplete evaluation: Missing extranodal sites can lead to understaging and suboptimal treatment
• Overlooking hepatitis B status: Reactivation of hepatitis B can occur during rituximab therapy
• Inadequate cardiac assessment: Doxorubicin in R-CHOP can cause cardiotoxicity

Special Molecular Considerations

• The presence of MYC rearrangement in combination with BCL2 rearrangement ("double-hit" lymphoma) carries prognostic significance 1
• Assessment using fluorescence in situ hybridization is recommended for patients being treated with curative intent 1

Follow-Up Planning

• Evaluation after 3-4 cycles and after completion of therapy
• Regular follow-up visits:
  • Every 3 months for 1 year
  • Every 6 months for 2 more years
  • Then annually
• Attention to secondary tumors and long-term side effects 5

The comprehensive staging workup will determine the extent of disease and guide the optimal treatment approach, which is crucial for maximizing the chance of cure in this potentially curable malignancy.