Determining Advanced-Stage Lymphoma
Advanced-stage lymphoma (Stage III or IV) is determined by identifying nodal involvement on both sides of the diaphragm (Stage III) or additional noncontiguous extralymphatic organ involvement (Stage IV) using PET-CT for FDG-avid lymphomas or CT for non-avid histologies. 1
Imaging Modality Selection
- PET-CT is the standard imaging technique for staging all FDG-avid lymphomas (including Hodgkin lymphoma and most aggressive non-Hodgkin lymphomas), while CT alone is used for non-avid histologies 1
- PET-CT has replaced CT as the gold standard because it provides superior accuracy in detecting both nodal and extranodal disease 2
Defining Advanced Stage: Anatomic Criteria
Stage III disease includes:
- Lymph nodes on both sides of the diaphragm 1
- Nodes above the diaphragm with spleen involvement (spleen is considered nodal tissue) 1
Stage IV disease includes:
- Any additional noncontiguous extralymphatic involvement in organs such as liver, bone marrow, lung parenchyma, or abdominal wall 3
- The "E" designation for extranodal extension is NOT relevant to advanced-stage disease—it only applies to limited disease (Stage IE or IIE with direct extension from adjacent nodes) 1, 3
Bone Marrow Assessment
- For Hodgkin lymphoma: bone marrow biopsy is no longer required when PET-CT is performed 1
- For diffuse large B-cell lymphoma (DLBCL): a positive PET scan showing bone or bone marrow involvement is sufficient to designate advanced-stage disease 1
- However, if PET is negative in DLBCL and identifying discordant histology would impact management (such as for clinical trial eligibility), bone marrow biopsy should be considered 1
- For other lymphoma histologies: a 2.5-cm unilateral bone marrow biopsy remains recommended, along with immunohistochemistry and flow cytometry 1
Stage II Bulky Disease Consideration
- Stage II bulky disease occupies a gray zone and may be treated as either limited or advanced disease depending on histology and prognostic factors 1
- Record the largest tumor diameter rather than using the "X" designation for bulky disease 1
B Symptoms: When They Matter
- Constitutional B symptoms (fever >38°C, night sweats, weight loss >10% over 6 months) only need to be documented for Hodgkin lymphoma, as they direct treatment decisions in that disease 1, 4
- For non-Hodgkin lymphomas, B symptoms are not included in major prognostic indices and do not need formal A/B designation 1
Common Pitfalls to Avoid
- Do not perform routine bone marrow biopsies in Hodgkin lymphoma patients undergoing PET-CT staging—this is outdated practice and adds unnecessary morbidity 1, 5
- Do not assign the "E" designation to patients with Stage IV disease—this is a frequent error, as "E" only applies to limited-stage disease with direct nodal extension 1, 3
- Ensure adequate tissue sampling at initial diagnosis (excisional biopsy preferred) to avoid repeat procedures 1