From the Guidelines
Laboratory evaluation for lymphadenopathy should begin with a complete blood count (CBC), comprehensive metabolic panel, and erythrocyte sedimentation rate (ESR) or C-reactive protein (CRP), as well as specific serologies based on clinical suspicion, and may include imaging studies such as chest X-ray or CT, and PET-CT scanning for staging if malignancy is confirmed, as recommended by the most recent guidelines 1.
Initial Evaluation
The initial evaluation of lymphadenopathy should include a thorough physical examination, complete medical history, and laboratory tests to identify potential causes.
- A complete blood count (CBC) to evaluate for infections, inflammatory conditions, or malignancies
- Comprehensive metabolic panel to assess liver and kidney function
- Erythrocyte sedimentation rate (ESR) or C-reactive protein (CRP) to evaluate for inflammation
Targeted Testing
Additional targeted testing should be based on clinical suspicion and may include:
- Specific serologies such as EBV, CMV, HIV, toxoplasmosis, or tuberculosis testing
- Cat scratch disease (Bartonella henselae serology) or tularemia testing if regional lymphadenopathy is present
Imaging Studies
Imaging studies such as:
- Chest X-ray or CT to evaluate for mediastinal lymphadenopathy or pulmonary disease
- PET-CT scanning for staging if malignancy is confirmed, as recommended by the most recent guidelines 1
Biopsy and Histopathological Assessment
For persistent unexplained lymphadenopathy, excisional lymph node biopsy is the gold standard for diagnosis, as it preserves nodal architecture necessary for accurate histopathological assessment 2.
- Fine needle aspiration may be considered initially but has limitations in diagnosing lymphoma
- Flow cytometry and cytogenetic studies on biopsy specimens help characterize lymphoproliferative disorders
Staging and Risk Assessment
Staging and risk assessment should be performed according to the Ann Arbor classification system, and may include:
- FDG-PET/CT scan as the gold standard for staging DLBCL patients 3
- Bone marrow biopsy and aspirate to evaluate for bone marrow involvement
- Screening tests for HIV, HBV, and HCV to evaluate for infectious disease status
Geriatric Assessment
Geriatric assessment may be useful to assess fitness in older lymphoma patients, as demonstrated for patients with CLL 1.
- Prognostication by the ‘Follicular Lymphoma-specific International Prognostic Index’ (FLIPI) or the revised FLIPI 2 may be recommended, whenever possible 1.
From the Research
Lymphadenopathy Labs
- Lymphadenopathy is typically evaluated through a combination of physical examination, medical history, and laboratory tests, including blood tests and imaging studies 4.
- The choice of laboratory tests depends on the clinical presentation, location of the lymphadenopathy, and underlying risk factors 4.
- Laboratory findings that may be associated with malignancy include leukopenia, thrombocytopenia, and increased lactate dehydrogenase levels 5.
- Erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) are markers of inflammation that can be used to monitor inflammatory conditions, but they lack sensitivity and specificity and should be used in combination with clinical history and physical exam 6, 7.
- In children, the diagnostic evaluation of peripheral lymphadenopathy is mainly based on clinical grounds, with laboratory tests such as complete blood count, ESR, and CRP used to support the diagnosis 8.
Laboratory Tests
- Complete blood count (CBC) may be used to evaluate for cytopenia, which is associated with malignancy 5.
- ESR and CRP may be used to monitor inflammatory conditions, but their results should be interpreted in the context of clinical history and physical exam 6, 7.
- Lactate dehydrogenase (LDH) levels may be elevated in cases of malignancy 5.
- Imaging studies, such as ultrasound or computed tomography (CT) scans, may be used to evaluate the location and extent of lymphadenopathy 4.
Special Considerations
- In children, the presence of systemic symptoms such as fever, night sweats, and unexplained weight loss may indicate a more serious underlying condition 4, 8.
- The location of the lymphadenopathy, such as supraclavicular or intra-abdominal, may be associated with a higher risk of malignancy 4, 5.
- The presence of splenomegaly may be associated with malignancy 5.