Chronic myeloid leukaemia is a cancerous disorder of the bone marrow characterized by an abnormal rise in the number of some of the cell types the bone marrow produces. CML makes up for about 20% out of every leukaemia type, even though it is considered an uncommon illness, affecting roughly 1 person out of 100000. The average age of appearance is of 55 years, being rare in the early stages of life.
In this article, we will give an answer to the most common questions about this illness.
What Are The Symptoms Of Chronic Myeloid Leukaemia? How Is It Diagnosed?
This illness is included within a group of illnesses called Myeloproliferative Neoplasms, having a slow evolution as their main trait.
Generally, diagnosis is often made in an asymptomatic, mild phase known as the chronic phase. Until the arrival of current pharma, IRS evolution was often staying in this chronic phase during 3 to 5 years, to later evolve to an accelerated phase and then into a blastic phase. In this blastic phase, it is as severe as acute leukemia, thus it has a very bad prognosis. Luckily, due to the treatments available nowadays, the chance of evolving into blastic phase is of less than 10%.
The most frequent appearance of this illness is by alterations in lab results. Said alterations consist mainly in a sharp increase of white cell and platelet count. In around 30% of patients, on top of these altered values, they might manifest general tiredness, weight loss, profuse sweating, bone and joint pain, bleeding, concurrent infections or abdominal pains due to splenomegaly (swelling of the spleen).
After suspecting the appearance of this illness, more blood tests along with spinal fluid tests must be carried out to confirm it. Diagnosis will be confirmed after the detection of an anomalous chromosome called the Philadelphia Chromosome. As a complementary test, an oncogene called BCR-ABL must be found; the presence or absence of this gene can determine how the person will respond to the treatment.
How is Chronic Myeloid Leukaemia Treated?
The current treatment for CML consists of compounds called tyrosine kinase inhibitors (TKIs) which, at first, must be taken indefinitely. Imatinib was the first medication deemed safe to treat it. Nilotinib, dasatinib, and bosutinib were the next to come, and as such they are known as second-generation inhibitors. Ponatinib is the latest medication to treat CML and is known as a third-generation TKI.
Both nilotinib and dasatinib are indicated in newly diagnosed patients as in patients who haven’t responded well to imatinib, which can occur in up to 40 per cent of patients. Bosutinib and ponatinib are approved in patients that don’t respond well to 2nd-gen TKI treatments. A small percentage of patients can develop a genetic mutation called T315I, which confers resistance to both 1st and 2nd-gen treatments; in these cases, ponatinib is a must.
Bone marrow transplant, considered during years the treatment of choice in most patients with CML, is now reserved for patients who don’t respond well to any TKI-based treatment at all, which can happen in less than 10% of the affected population.
What Is The Prognosis For CML Patients?
Prognosis for CML has suffered a drastic change in the last decades. With the arrival of TKI-based treatments, the life expectancy of an affected person has changed from 5 years after diagnosis to the average life expectancy of an unaffected person, as long as the diagnosis has occurred in the chronic phase. This means that nowadays, the survivability rate is well above 90%, with the fatalities in the affected being mostly unrelated to the illness…
Because of this, it is of utmost importance that the patient expresses their situation to a specialist who knows every option available. These options might also contemplate the treatment of the disease through interferons; this could be the case for pregnant women.
Does The Treatment Have Any Side Effects?
TKIs are generally well-tolerated. It is frequent, though, that the patients experience transient side effects in the first months of treatment. Among these, we can find nausea, liquid retention, abdominal pains or cramps. Most of these side effects can be handled with reductions in the dosage, over-the-counter (OTC) aides or dietary restrictions. There are other side effects that are related to how the patient responds to 1st and 2nd-gen TKIs, which makes the treatment election a well-studied and careful process, adapted specifically to each patient.
Will, I Have To Take Medication Forever?
Despite TKIs manage to control the illness in the vast majority of patients, the general indication is sticking to the treatment indefinitely. However, there are well-documented cases of patients with an excellent response to TKIs have been able to suspend their treatment safely after several years. This possibility of suspension is now part of 2nd-gen treatments such as nilotinib. It is important to bear in mind that this suspension must be performed only in some patients under a strict follow-up regime.