From the Guidelines
The best laboratory tests to assess for lymphoma include a complete blood count (CBC), comprehensive metabolic panel, lactate dehydrogenase (LDH), and erythrocyte sedimentation rate (ESR), with definitive diagnosis requiring tissue biopsy, typically an excisional lymph node biopsy, as well as flow cytometry and immunohistochemistry to determine lymphoma subtype. According to the most recent and highest quality study 1, a complete blood count, routine blood chemistry including lactate dehydrogenase (LDH) and uric acid, as well as screening tests for HIV, hepatitis B virus (HBV), and HCV are required for the initial evaluation of lymphoma. Some key points to consider when assessing for lymphoma include:
- Tissue biopsy is essential for definitive diagnosis, with excisional lymph node biopsy preferred over fine needle aspiration due to the need for architecture assessment 1.
- Flow cytometry analyzes cell surface markers to identify abnormal lymphocyte populations, while immunohistochemistry helps determine lymphoma subtype 1.
- Cytogenetic and molecular studies detect specific genetic abnormalities associated with certain lymphoma types, and may be necessary for accurate diagnosis and treatment planning 1.
- Additional tests, such as CT scans, PET scans, and MRI, are used for staging and assessing disease spread, with PET-CT being the standard for FDG-avid lymphomas 1.
- Bone marrow biopsy may be necessary to assess disease spread, although focal bone marrow FDG uptake with or without increased diffuse uptake is more sensitive than bone marrow biopsy for infiltration in DLBCL 1. It's also important to note that laboratory findings like elevated LDH often correlate with more aggressive disease and poorer prognosis, making them valuable for both diagnosis and monitoring treatment response 1.
From the Research
Laboratory Tests for Lymphoma Assessment
The following laboratory tests are used to assess for lymphoma:
- Bone marrow biopsies and flow cytometry to detect lymphoma cells in the bone marrow 2
- Positron emission tomography (PET) scans to evaluate bone marrow involvement and detect extranodal disease 3, 4
- Serum markers such as lactate dehydrogenase (LDH), beta-2 microglobulin (B2M), and thymidine kinase (TK) to classify risk and predict treatment outcomes for large cell lymphoma 5
- Immunohistochemistry and flow cytometry with specific antibody panels to diagnose and distinguish between different types of lymphoma, such as mantle cell lymphoma and chronic lymphocytic leukemia/small lymphocytic lymphoma 6
Key Findings
- Bone marrow flow cytometry can detect small numbers of lymphoma cells and is a useful complementary method to histomorphology in staging non-Hodgkin lymphoma 2
- PET/CT scans have limited sensitivity and specificity in detecting bone marrow involvement in diffuse large B-cell lymphoma, and bone marrow biopsy remains a necessary step in staging 3
- Serum markers such as LDH, B2M, and TK can be used to classify risk and predict treatment outcomes for large cell lymphoma 5
- Specific antibody panels and immunohistochemical stains can help diagnose and distinguish between different types of lymphoma, such as mantle cell lymphoma and chronic lymphocytic leukemia/small lymphocytic lymphoma 6
Test Characteristics
- Bone marrow flow cytometry: sensitive and specific for detecting lymphoma cells in bone marrow, especially when used in combination with histomorphology 2
- PET/CT scans: limited sensitivity and specificity for detecting bone marrow involvement in diffuse large B-cell lymphoma, but useful for evaluating extranodal disease 3, 4
- Serum markers: useful for classifying risk and predicting treatment outcomes for large cell lymphoma, but require careful interpretation and consideration of other clinical factors 5
- Immunohistochemistry and flow cytometry: essential for diagnosing and distinguishing between different types of lymphoma, and require specific antibody panels and expertise 6