Managing advanced phase chronic myeloid leukemia

This study reviewed treatment options for advanced phase chronic myeloid leukemia. This study concluded that managing advanced phase chronic myeloid leukemia remains challenging and treatment options include tyrosine kinase inhibitors, chemotherapy, and transplant. 

Chronic myeloid leukemia (CML) can be classed as chronic phase (CP-CML) or advanced phase CML. The advanced phase is split into an accelerated phase (AP-CML) and blast phase (BP-CML).  

CP-CML is when less than 10% blasts (immature white blood cells) can be found in the blood. This phase can last several years. This is the stage where patients are usually diagnosed. Without effective treatment, disease can progress to AP-CML or BP-CML. AP-CML is when there are 10% to 19% blasts in the blood. BP-CML is when there are 20% or more blasts. Less than 5% of patients are in these phases when initially diagnosed. 

The management of patients with advanced phase CML remains challenging.

The management of AP and BP-CML is a challenge even with tyrosine kinase inhibitors (TKIs). TKIs are a type of targeted therapy used in cancer treatment. They work to block enzymes called tyrosine kinases which allow cell growth and division. These enzymes are overactive in cancer and TKIs block them. Resistance is a problem that limits the benefit of treatment in these patients. There have been few studies in this area due to the low number of patients in AP- and BP-CML. 

The outcomes for patients with CML diagnosed in advanced phase have improved over time. Currently, most patients with advanced phase features at diagnosis can be managed as high-risk CP patients.   

Patients diagnosed with advanced phase are at higher risk of treatment failure compared to CP patients. However, if they achieve optimal responses with frontline TKI their outcome may be similarly favorable.  

Patients in blast crisis have poorer outcomes due to resistance to TKI. In advanced phase CML, TKI and chemotherapy, or novel agents including immunotherapy could improve outcomes. Patients diagnosed in BP may be treated with TKI alone or TKI plus chemotherapy and transplant. 

Patients in CP with disease progression during TKI treatment are the most challenging group. They should be treated with other TKIs based on gene abnormalities. Optional chemotherapy should be considered in BP patients. Also, transplant should be considered where suitable after a return to second CP. 

Due to lack of reliable prediction of blast crisis and treatment failure, preventing disease progression by choosing frontline treatment in CP and early intensive treatment in non-optimal responders is the main goal.  

This study concluded that managing advanced phase CML remains challenging and treatment options include TKIs, chemotherapy, and transplant.