Table 1.
Criteria for Involvement of Site
| Tissue Site | Clinical | FDG Avidity | Test | Positive Finding |
|---|---|---|---|---|
| Lymph nodes | Palpable | FDG-avid histologies | PET-CT | Increased FDG uptake |
| Nonavid disease | CT | Unexplained node enlargement | ||
| Spleen | Palpable | FDG-avid histologies | PET-CT | Diffuse uptake, solitary mass, miliary lesions, nodules |
| Nonavid disease | CT | > 13 cm in vertical length, mass, nodules | ||
| Liver | Palpable | FDG-avid histologies | PET-CT | Diffuse uptake, mass |
| Nonavid disease | CT | Nodules | ||
| CNS | Signs, symptoms | CT | Mass lesion(s) | |
| MRI | Leptomeningeal infiltration, mass lesions | |||
| CSF assessment | Cytology, flow cytometry | |||
| Other (eg, skin, lung, GI tract, bone, bone marrow) | Site dependent | PET-CT*, biopsy | Lymphoma involvement |
Abbreviations: CSF, cerebrospinal fluid; CT, computed tomography; FDG, fluorodeoxyglucose; MRI, magnetic resonance imaging; PET, positron emission tomography.
*
PET-CT is adequate for determination of bone marrow involvement and can be considered highly suggestive for involvement of other extralymphatic sites. Biopsy confirmation of those sites can be considered if necessary.