Definition, methods, and time points for remission assessment in current treatment protocols for pediatric ALL (remission requires fulfillment of all sites)
| Anatomic sites . | Methods . | Study group . | Time point, d . | Exceptions . |
|---|---|---|---|---|
| BM | ||||
| <5% blasts in BM | Cytomorphology | AIEOP-BFM ALL-IC BFM CoALL DCOG DFCI JCCG TPOG | 33, EOI 33, EOI 29, EOI 33, EOI 32, EOI 33, EOI 35-42, EOI | |
| <5% blasts in BM | Cytomorphology plus confirmation by FCM-/PCR-MRD/genetics | NOPHO SEHOP-PETHEMA SFCE SJCRH | 29, EOI EOI 35-42, EOI 38-42, EOI | SJCRH mainly uses FCM-MRD |
| <5% blasts in BM | PCR-MRD (±cytomorphology) | UKALL | 29, EOI | |
| <1% blasts in BM | FCM-/PCR-MRD (±cytomorphology) | ALLTogether COG EsPhALL/COG | EOI as the earliest EOI for early CR, EOC for late CR End of Cons. block 3 | |
| CNS | ||||
| CNS 1 | Cytomorphology, imaging, clinical examination | Every participating study group | See above for respective study group | |
| CNS 1 | Cytomorphology plus confirmation by FCM-MRD | ALLTogether | See above for respective study group | If suspect cells are seen; evaluation at EOC (d 71) |
| EM | ||||
| Resolution of leukemic infiltrates | Clinical examination, imaging, histology | ALL-IC COG DCOG JCCG EsPhALL/COG | See above for respective study group | DCOG: retesting of testicular involvement after Prot. M NOPHO: retesting EM involvement at d 85 |
| Reduction of initial leukemic mass to 1/3 | Clinical examination, imaging, histology | AIEOP-BFM ALLTogether CoALL DFCI SEHOP-PETHEMA SFCE UKALL | See above for respective study group | UKALL: retesting of testicular involvement at wk 8 |
| Anatomic sites . | Methods . | Study group . | Time point, d . | Exceptions . |
|---|---|---|---|---|
| BM | ||||
| <5% blasts in BM | Cytomorphology | AIEOP-BFM ALL-IC BFM CoALL DCOG DFCI JCCG TPOG | 33, EOI 33, EOI 29, EOI 33, EOI 32, EOI 33, EOI 35-42, EOI | |
| <5% blasts in BM | Cytomorphology plus confirmation by FCM-/PCR-MRD/genetics | NOPHO SEHOP-PETHEMA SFCE SJCRH | 29, EOI EOI 35-42, EOI 38-42, EOI | SJCRH mainly uses FCM-MRD |
| <5% blasts in BM | PCR-MRD (±cytomorphology) | UKALL | 29, EOI | |
| <1% blasts in BM | FCM-/PCR-MRD (±cytomorphology) | ALLTogether COG EsPhALL/COG | EOI as the earliest EOI for early CR, EOC for late CR End of Cons. block 3 | |
| CNS | ||||
| CNS 1 | Cytomorphology, imaging, clinical examination | Every participating study group | See above for respective study group | |
| CNS 1 | Cytomorphology plus confirmation by FCM-MRD | ALLTogether | See above for respective study group | If suspect cells are seen; evaluation at EOC (d 71) |
| EM | ||||
| Resolution of leukemic infiltrates | Clinical examination, imaging, histology | ALL-IC COG DCOG JCCG EsPhALL/COG | See above for respective study group | DCOG: retesting of testicular involvement after Prot. M NOPHO: retesting EM involvement at d 85 |
| Reduction of initial leukemic mass to 1/3 | Clinical examination, imaging, histology | AIEOP-BFM ALLTogether CoALL DFCI SEHOP-PETHEMA SFCE UKALL | See above for respective study group | UKALL: retesting of testicular involvement at wk 8 |
BM: bone marrow, CNS: central nervous system, d: day, EM: extramedullary sites, EOC: end of consolidation, EOI: end of induction, FCM-MRD: flow cytometric minimal residual disease, MRD: minimal residual disease, PCR-MRD: polymerase chain reaction minimal residual disease.