Recommendations for cytogenetic and molecular monitoring
| At diagnosis | Chromosome banding analysis (CBA) of marrow cell metaphases |
| FISH in case of Ph negativity to identify variant, cryptic translocations | |
| Qualitative PCR (identification of transcript type) | |
| During treatment | Quantitative real-time PCR (RQ-PCR) for the determination of BCR-ABL1 transcripts level on the international scale, to be performed every 3 months until an MMR (BCR-ABL ≤0.1%, or MR3.0) has been achieved, then every 3 to 6 months |
| and/or | |
| CBA of marrow cell metaphases (at least 20 banded metaphases), to be performed at 3, 6, and 12 months until a CCyR has been achieved, then every 12 months. Once a CCyR is achieved, FISH on blood cells can be done. If adequate molecular monitoring can be ensured, cytogenetics can be spared. | |
| Failure, progression | RQ-PCR, mutational analysis, and CBA of marrow cell metaphases. Immunophenotyping in BP. |
| Warning | Molecular and cytogenetic tests to be performed more frequently. CBA of marrow cell metaphases recommended in case of myelodysplasia or CCA/Ph– with chromosome 7 involvement. |
| At diagnosis | Chromosome banding analysis (CBA) of marrow cell metaphases |
| FISH in case of Ph negativity to identify variant, cryptic translocations | |
| Qualitative PCR (identification of transcript type) | |
| During treatment | Quantitative real-time PCR (RQ-PCR) for the determination of BCR-ABL1 transcripts level on the international scale, to be performed every 3 months until an MMR (BCR-ABL ≤0.1%, or MR3.0) has been achieved, then every 3 to 6 months |
| and/or | |
| CBA of marrow cell metaphases (at least 20 banded metaphases), to be performed at 3, 6, and 12 months until a CCyR has been achieved, then every 12 months. Once a CCyR is achieved, FISH on blood cells can be done. If adequate molecular monitoring can be ensured, cytogenetics can be spared. | |
| Failure, progression | RQ-PCR, mutational analysis, and CBA of marrow cell metaphases. Immunophenotyping in BP. |
| Warning | Molecular and cytogenetic tests to be performed more frequently. CBA of marrow cell metaphases recommended in case of myelodysplasia or CCA/Ph– with chromosome 7 involvement. |
The responses can be assessed either with molecular tests alone or with cytogenetic tests alone, depending on the local laboratory facilities, but whenever possible, both cytogenetic and molecular tests are recommended until a CCyR and an MMR are achieved. Then RQ-PCR alone may be sufficient. Mutational analysis by conventional Sanger sequencing is recommended in case of progression, failure, and warning.59 In case of failure, warning, and development of myelodysplastic features (unexpected leucopenia, thrombocytopenia, or anemia), CBA of marrow cell metaphases is recommended.
FISH, fluorescence in situ hybridization; CCA/Ph–,clonal chromosome abnormalities in Ph– cells.