There are 3 stages of CML.

1. Chronic phase,
2. Accelerated phase &
3. Blast phase.

CHRONIC PHASE:

• It is characterized by less than 10% blast cells in blood & bone marrow.
• Wbc capable of fighting infections.

ACCELERATED PHASE:

• 10-19% blast cells in blood & bone marrow.
• High basophil count >20% of wbcs.
• Persistent thrombocytopenia unrelated to therapy.
• Persistent thrombocytosis.
• Increasing wbcs & spleen unresponsive to therapy.
• There is fever, poor appetite & weight loss.

BLAST CRISIS:

• > 25% blast cells in blood & bone marrow.
• There is fever, loss of apetite, weight loss, fatigue, bleeding, infections common, bone pain. 

PARTIAL HEMATOLOGICAL REMISSION IN CML is defined as:

• Wbc count <10000.
• Platelet count <50% of pretreatment count  but greater than 450000.
• Persistent splenomegaly but <50%of pretreatment extent.

COMPLETE HEMATOLOGICAL REMISSION:

• WBCS <10000.
• Platelat count <450000.
• No immature cells such as blasts, promyelocytes & metamyelocytes.
• Disapperance of palpable spleen.

CYTOGENETIC REMISSION:

• normal chromosomes return with 0% Philadelphia chromosomes. This is detected by karyotyping or FISH technique.
• Major cytogenetic response:0-35%
•  Ph chromosomes.

Minor cytogenetic response:

• 1-34% Philadelphia positive chromosomes.

MOLECULAR RESPONSE: 

• there should be negative PCR results for BCR/ABL mRNA. Detected by measuring quantitave pcr.

Complete molecular response:

• BCR-abl mRNa undetected by PCR.

Major molecular response:

• > 3 log reduction of bcr-abl mRNA which should be acheived within 12 months.