Table 4.
Differential diagnostic criteria for pediatric (atypical) marginal zone hyperplasia, pediatric nodal marginal zone lymphoma, and nodular lymphocyte predominant Hodgkin lymphoma
| Atypical MZH | PNMZL | NLPHL | |
|---|---|---|---|
| Marginal zone hyperplasia | + | + | −/+ |
| Follicular hyperplasia | +/− | +/− | − |
| PTGC-like changes | + | + | + |
| Light chain restriction | +/− (lambda) | +/− | Rare |
| Ki-67 | High in GC | Relatively increased in MZ and high in residual GC | High in residual GC and LP cells |
| TFH-rosettes | Absent | Absent (increased TFH lymphocytes) | Present |
| LP-cells | Absent | Absent (sometimes cytologic atypia) | Present |
| Immunoglobulin clonality analysis | Polyclonal | Clonal | Usually polyclonal (due to low tumor cell content) |
| Mutational analysis | Negative | Sometimes TNFRSF14, MAP2K1, IRF8 mutations | Usually neg. (low tumor cell content) or STAT6, SOCS1, etc. |
MZH, marginal zone hyperplasia; PNMZL, pediatric nodal marginal zone lymphoma; NLPHL, nodular lymphocyte-predominant Hodgkin lymphoma; ISH, in situ hybridization; GC, germinal centers; MZ, marginal zone; LP, lymphocyte-predominant; TFH, T follicular helper