By Thihan Padukkavidana
This article originally appeared on LinkedIn on September 21, 2020
Chronic myeloid leukemia, or CML, is one of four main types of leukemia.1 CML is a rare blood cancer that forms in certain cells in a person’s bone marrow.2 While tens of thousands of people are diagnosed with leukemia every year in the U.S., only about 8,000 have CML.3 As a result, some healthcare professionals may never treat someone living with CML throughout the course of their career.
As a Scientific Director on the Medical Affairs team at Takeda Oncology, I study leukemias – including CML – every day. Within this role, I have had the opportunity to work closely with researchers, healthcare providers, patients and caregivers impacted by CML. These people all inspire me, and I am driven every day by the potential ability to positively impact patients’ lives.
In recognition of Blood Cancer Awareness Month this September, and specifically World Leukemia Day on September 4 and World CML Day on September 22, I wanted to share my experience working in CML. While many diagnosed with CML will have success with their treatment, others will unfortunately encounter challenges throughout the course of their disease. I’ve heard that CML has been described to certain patients as a “good cancer” upon diagnosis, yet the five-year survival rate is only about 70% and more than 1,000 people are estimated to succumb to CML in a year in the U.S.3-5
I believe there is still much more we can do to improve our understanding of CML and the importance of offering various treatment options that address each patient’s unique case. By sharing my perspective, I hope that I am able to help raise awareness about this rare blood cancer and advocate for better outcomes and experiences for those who suffer with CML.
The Basics: What is CML?
CML occurs when a genetic change takes place in early, immature versions of cells that form red blood cells, platelets and most types of white blood cells.1 This change involves pieces of chromosomes 9 and 22 switching with each other, forming the Philadelphia chromosome.8 As a result, the abnormal gene BCR-ABL1 is formed, which leads to the cell becoming damaged and cancerous.
CML is often hard to diagnose early because patients do not always present with symptoms and when they do, symptoms can be non-specific. As a result, CML is sometimes diagnosed through routine blood tests performed for other reasons.7 CML typically progresses slowly but can change into a fast-growing acute leukemia in some patients that is hard to treat, particularly if poorly managed.1
The Progression & Evolution of CML
While CML is often well-controlled with daily oral therapies known as tyrosine kinase inhibitors, or TKIs, treatment failure is a setback for some patients. TKI treatment failure can occur for a variety of reasons. In fact, about one quarter of people living with CML will need to adjust their first TKI treatment at one point during the course of their disease, as they may no longer be able to tolerate the initial TKI therapy, or the initial TKI therapy may stop working. People living with CML can become intolerant (meaning that side effects or toxicity leads to discontinuation of treatment with a certain TKI) or resistant (meaning that they lack or lose response to the TKI).8-12
Because of the potential for treatment failure, it is important to have regular milestone tests to identify if a patient’s current treatment is still the best option. Regular monitoring is recommended to help ensure that a person’s current treatment plan remains effective and well tolerated. Regular monitoring is also critical as patients may not always experience new symptoms when a treatment is no longer working. Understanding the reason that a TKI fails is a necessary aspect of deciding the next step in each person’s individualized treatment plan. Fortunately, there are a number of options, even if a prescribed TKI is no longer working for someone with CML.13
The Importance of CML Awareness
Blood Cancer Awareness Month and World CML Day are important moments for me because I’ve learned that CML can often be mischaracterized. Through my work, I’ve had the opportunity to interact with people living with CML. CML is often asymptomatic and not commonly discussed, therefore it can be hard to diagnose early and may lead to surprise upon diagnosis. Furthermore, the potential for treatment failure is not always expected and proactively explained, partially due to this “good cancer” misconception, and those who have had to make adjustments in their treatment regimens have explained to me feelings of surprise and disappointment.4
These stories inspire me to work to improve treatment and the patient experience. To honor Blood Cancer Awareness Month and World CML Day, I hope that I can help highlight the unique experiences of those impacted by CML.
CML is a complex disease, and each person living with CML is unique. Tackling CML requires a thorough understanding of the disease and the ability to always look for new answers and solutions based on individual needs. For more information about CML, I’d encourage you to seek out educational resources from one of the many CML advocacy organizations that exist.
1American Cancer Society. https://www.cancer.org/cancer/chronic-myeloid-leukemia/about/what-is-cml.html. Accessed September 2020.
2MacMillan Cancer Support. https://www.macmillan.org.uk/cancer-information-and-support/leukaemia#:~:text=Chronic%20myeloid%20leukaemia%20(CML)%20is,will%20live%20a%20normal%20lifespan. Accessed September 2020.
3American Cancer Society. https://www.cancer.org/cancer/chronic-myeloid-leukemia/about/statistics.html. Accessed September 2020.
4Leukemia & Lymphoma Society. https://pages.lls.org/mwoy/soh/cincy20/tscull. Accessed September 2020.
5SEER Cancer Stat Facts National Cancer Institute. Bethesda, MD, https://seer.cancer.gov/statfacts/html/cmyl.html. Accessed September 2020.
6Leukemia & Lymphoma Society. https://www.lls.org/leukemia/chronic-myeloid-leukemia. Accessed September 2020.
7American Cancer Society. https://www.cancer.org/cancer/chronic-myeloid-leukemia/detection-diagnosis-staging/detection.html. Accessed September 2020.
8Hochhaus A, Saglio G, Hughes TP, et al. Leukemia. 2016;30(5):1044‐1054. ([incidence rates] P. 1046, Figure 1).
9Cortes JE, Saglio G, Kantarjian HM, et al. J Clin Oncol. 2016;34(20):2333-2340.
10Brümmendorf TH, Cortes JE, de Souza CA, et al.. Br J Haematol. 2015;168(1):69‐81.
11Leukemia and Lymphoma Society: https://www.lls.org/leukemia/chronic-myeloid-leukemia/treatment/tyrosine-kinase-inhibitor-tki-therapy Accessed September 2020.
12Khoury, H., et al. Blood. 2012;119(15): 3403-3412.
13Cancer.Net https://www.cancer.net/cancer-types/leukemia-chronic-myeloid-cml/types-treatment Accessed September 2020.