How to confirm a diagnosis of lymphoma suggested by Contrast-Enhanced Computed Tomography (CECT) of the abdomen?

From the Guidelines

To confirm a diagnosis of lymphoma suggested by Contrast-Enhanced Computed Tomography (CECT) of the abdomen, a tissue biopsy is essential, typically involving excisional biopsy of an accessible lymph node or image-guided core needle biopsy of the affected area, as imaging alone cannot distinguish lymphoma from other conditions. When a CECT abdomen suggests lymphoma, the next steps should involve further diagnostic testing to confirm the diagnosis and assess the extent of the disease.

• Key diagnostic procedures include:
  • Tissue biopsy for histopathological examination, immunohistochemistry, and flow cytometry to determine the specific lymphoma type 1.
  • Complete blood count and lactate dehydrogenase (LDH) levels to assess the patient's overall condition and potential tumor burden.
  • Bone marrow biopsy to check for lymphoma involvement in the bone marrow.
  • PET-CT scan for staging, especially for FDG-avid lymphomas, as recommended by the Lugano classification 1.
• The choice between PET-CT and CT scan for staging depends on the lymphoma type, with PET-CT preferred for FDG-avid lymphomas and CT scan for other types 1.
• A multidisciplinary approach involving hematologists, oncologists, radiologists, and pathologists is crucial for accurate diagnosis and treatment planning.
• Early diagnosis through proper tissue sampling is critical for initiating appropriate treatment and improving patient outcomes.
• The Lugano classification provides guidelines for the initial evaluation, staging, and response assessment of Hodgkin and non-Hodgkin lymphoma, emphasizing the role of PET-CT and CT scans in disease assessment 1.

From the Research

Confirming a Diagnosis of Lymphoma

To confirm a diagnosis of lymphoma suggested by Contrast-Enhanced Computed Tomography (CECT) of the abdomen, the following steps can be taken:

• An open lymph node biopsy is preferred for diagnosis 2
• Core-needle biopsy (CNB) can be considered as a less invasive alternative to excisional biopsy (EB) 3
• Positron emission tomography/computed tomography (PET/CT)-driven biopsy can be used to drive biopsy to the most metabolically active area within a lymph node or extranodal masses 4
• Image-guided core needle biopsy can be used to assess the diagnostic accuracy of malignant lymphoma 5
• Fine needle aspiration biopsy (FNAB) with adjuvant flow cytometry (FC) can be used to diagnose and subtype lymphomas, and core biopsy can be used to obtain additional diagnostic and prognostic information 6

Diagnostic Techniques

The diagnostic techniques used to confirm a diagnosis of lymphoma include:

• Open lymph node biopsy
• Core-needle biopsy (CNB)
• Positron emission tomography/computed tomography (PET/CT)-driven biopsy
• Image-guided core needle biopsy
• Fine needle aspiration biopsy (FNAB) with adjuvant flow cytometry (FC) These techniques can provide sufficient diagnostic information to allow treatment of malignant lymphoma to be instigated 3, 4, 5, 6

Advantages and Disadvantages of Diagnostic Techniques

The advantages and disadvantages of the diagnostic techniques used to confirm a diagnosis of lymphoma are:

• Open lymph node biopsy: considered the gold standard, but requires hospitalization and has associated drawbacks 2
• Core-needle biopsy (CNB): less invasive, shorter time to biopsy, and can be considered an alternative to EB 3
• Positron emission tomography/computed tomography (PET/CT)-driven biopsy: minimally invasive, timely, and accurate diagnosis of lymphoma at onset or relapse 4
• Image-guided core needle biopsy: well tolerated, reduced costs, post-procedural complications, and delays on the diagnostic pathway 5
• Fine needle aspiration biopsy (FNAB) with adjuvant flow cytometry (FC): useful for diagnosing and subtyping lymphomas, but may not provide sufficient diagnostic information in all cases 6