Table 3.
Additional Staging Information
| Additional Staging Information |
|---|
| BM involvement |
| Stage IV disease, resulting from BM involvement, is currently defined by morphologic evidence of ≥ 5% blasts or lymphoma cells by BM aspiration; this applies to any histologic subtype and will be maintained in IPNHLSS |
| For each stage, type and degree of BM involvement (by BM aspiration) should be specified, using abbreviations below to identify involvement: |
| BMm: BM positivity by morphology (specify % lymphoma cells) |
| BMi: BM positivity by immunophenotypic methods (immunohistochemical or flow-cytometric analysis; specify % lymphoma cells) |
| BMc: BM positivity by cytogenetic or FISH analysis (specify % lymphoma cells) |
| BMmol: BM positivity by molecular techniques (PCR based; specify level of involvement) |
| Same approach should be used for PB involvement (ie, PBm, PBi, PBc, PBmol) |
| Definition of BM involvement should be obtained from analysis of bilateral BM aspirates and BM biopsy |
| CNS involvement |
| CNS is considered involved in case of: |
| Any CNS tumor mass (identified by imaging techniques [ie, CT, MRI]) |
| Cranial nerve palsy that cannot be explained by extradural lesions |
| Blasts morphologically identified in CSF |
| Condition that defines CNS positivity should be specified: CNS positive/mass, CNS positive/palsy, CNS positive/blasts |
| CSF status: CSF positivity is based on morphologic evidence of lymphoma cells |
| CSF should be considered positive when any No. of blasts is detected |
| CSF unknown (not performed, technical difficulties) |
| Similarly to BM, type of CSF involvement should be described whenever possible |
| CSFm: CSF positivity by morphology (specify No. of blasts/μL) |
| CSFi: CSF positivity by immunophenotype methods (immunohistochemical or flow cytometric analysis; specify % lymphoma cells) |
| CSFc: CSF positive by cytogenetic or FISH analysis (specify % lymphoma cells) |
| CSFmol: CSF positivity by molecular techniques (PCR based; specify level of involvement) |
NOTE. Until sufficient data are available, PET should be used with caution for staging, and PET results should be compared and discussed in light of other more consolidated imaging approaches.
Abbreviations: BM, bone marrow; CT, computed tomography; FISH, fluorescent in situ hybridization; IPNHLSS, International Pediatric Non-Hodgkin Lymphoma Staging System; MRI, magnetic resonance imaging; PB, peripheral blood; PBc, PB positivity by cytogenetic or FISH analysis; PBi, PB positivity by immunophenotype methods; PBm, PB positivity by morphology; PBmol, PB positivity by molecular techniques; PCR, polymerase chain reaction; PET, positron emission tomography.