Markers used in lineage assignment
| Lineage . | Markers . |
|---|---|
| B lineage | |
| Strong CD19∗ and | ≥1 marker expression CD10, CD22, or CD79a |
| Weak CD19 and | ≥2 strongly expressed: CD10, CD22, CD79a |
| Consider immunohistochemical stains for B lineage | PAX5, OCT2, BOB1 |
| T lineage | |
| CD3 (surface or cytoplasmic) | — |
| Myeloid lineage | |
| MPO or | — |
| Monocytic differentiation | NSE, CD64, CD11c, CD14, or lysozyme |
| Lineage . | Markers . |
|---|---|
| B lineage | |
| Strong CD19∗ and | ≥1 marker expression CD10, CD22, or CD79a |
| Weak CD19 and | ≥2 strongly expressed: CD10, CD22, CD79a |
| Consider immunohistochemical stains for B lineage | PAX5, OCT2, BOB1 |
| T lineage | |
| CD3 (surface or cytoplasmic) | — |
| Myeloid lineage | |
| MPO or | — |
| Monocytic differentiation | NSE, CD64, CD11c, CD14, or lysozyme |
The immunophenotypic criteria described here are for cases of suspected MPAL and are not required for straightforward cases of AML or ALL.
Expression should be at least similar to that seen in stage I B-cell precursors or mature B cells.