Chronic Leukemia: What are the possible treatment options?

Contributed by: Dr Colin Phipps Diong

Treating Cancer Today: Chronic Leukemia

Chronic leukemia is highly treatable, says Dr Colin Phipps Diong, Senior Consultant in Haematology. This issue, we interview him to learn more about the treatment possibilities for different types of chronic leukemia, and what patients can expect during treatment.

What is leukemia?

Leukemia is a blood cancer that occurs when the bone marrow produces abnormal white blood cells that crowd out healthy cells and eventually enter the bloodstream.

Leukemia comes in many forms, each with its own unique characteristics, prognosis and treatment modalities.

In general, leukemia can be categorised into either chronic leukemia or acute leukemia. Compared to acute leukemia, which is rapid-growing and causes problems early in the course of the disease, chronic leukemia is slower-growing and insidious.

There are various subtypes of chronic leukemia, the two most common being chronic myeloid leukemia (CML) and chronic lymphocytic leukemia (CLL).

In CML, immature myeloid cells (cells that are responsible for creating red blood cells, platelets and certain white blood cells) undergo a genetic change due to a spontaneous mutation that results in an abnormal gene called BCR-ABL, turning the cell into a CML cell which then grows and divides uncontrollably.

In CLL, the cancer affects B-cell lymphocytes (a type of white blood cell that helps fight infections) in the bone marrow. CLL occurs when your body produces an abnormally high number of B-cells in your body and crowds out the healthy cells.

The role of precision medicine in chronic leukemia

Chronic leukemias have become highly treatable, shares Dr Colin.

He explains that whereas in the past, chemotherapy was the main treatment modality for these two subtypes of chronic leukemia, recent medical advancements have shifted the treatment paradigm to targeted therapy alone.

Targeted therapy refers to a type of precision medicine that targets specific genes and proteins that control the growth and spread of a cancer. Compared to traditional treatment modalities like chemotherapy, targeted therapy is more specific and will have much less negative effects on normal healthy cells.

The use of oral targeted therapies in chronic leukemias in place of conventional chemotherapy, for instance, means that patients spend less time in the hospital, and will not have the side effects or complications of chemotherapy.

What this means is that many, if not most patients are able to go to work and go about their day normally. In fact, a few CML studies with long follow-up have reported that CML patients on targeted therapies have life expectancies that are approaching that of the normal population.


Determining the appropriate treatment for each patient

In this era of targeted therapies, a key step in treating patients with chronic leukemia is to find the correct diagnosis and subtype of the disease.

As targeted drugs target specific proteins or genetic mutations within the leukemia cells to destroy or block their growth, the subtype of disease allows doctors to select the most appropriate drug that will target the relevant gene or protein causing the disease.

To determine this, patients would typically undergo a physical examination, blood test and bone marrow biopsy along with additional tests such as genetic testing and imaging tests. Such tests not only help to determine the diagnosis, prognosis and extent of the disease, but also helps determine the best treatment options available for the stage of the disease.

Patients can expect that all tests which are necessary at the point of diagnosis to be carried out at PCC, shares Dr Colin. Following this, appropriate therapy will be selected based on the patient's individual profile and disease state.

Effectiveness of targeted therapy for chronic leukemia

Today, thanks to modern medical developments, with oral medicine alone, patients with chronic leukemia can be treated to great degrees of success. The successful use of oral tyrosine kinase inhibitors, for instance, made CML the ‘poster child’ for targeted cancer therapy in the early 2000s.

Presently, oral targeted therapy is also routinely used for first-line treatment in CLL.

In the near future, there will be more and more targeted therapies coming into our clinics, shares Dr Colin. Some of these targeted therapies have even less side effects while some of these are more effective.

There are also studies looking at combinations of targeted therapies that may further improve the disease responses and increase the rate of cure. The results of these will be available to us in the near future, allowing us to better provide more accurate and precise treatment options to patients with the disease.

POSTED IN Cancer Treatments
TAGS blood cancer, bone marrow, chemotherapy, targeted therapy
READ MORE ABOUT Chronic Lymphocytic Leukaemia (CLL), Chronic Myeloid Leukaemia (CML)
PUBLISHED 14 JULY 2021