For decades, until the turn of this century, treatment strategies for leukemia changed very little. Patients received chemotherapy, often with a combination of agents to eliminate cancerous white blood cells, followed by bone-marrow transplants to replenish healthy ones. They received these treatments regardless of age, gender or family history. The treatments were truly one size fits all.
Today, blood cancer specialists have options. We can take advantage of genomic testing to identify the specific genetic mutations that characterize a patient’s cancer, and offer new precision medications that target cancer-driving proteins. Together, this offers patients precision medicine targeted specifically to their cancer type.
We can also use detailed genetic information about each patient’s cancer to select the most effective treatment with the lowest possible toxicity — improving outcomes and quality of life, while decreasing and sometimes eliminating side effects.
What’s more, oncologists are now identifying obstacles to treatment using new data focused on the social determinants of health — non-medical factors in people’s lives that influence their health outcomes. When those obstacles are identified, they can be overcome to get people the care they need.
Combined, these new approaches mean that treatment is highly personized, more effective and easier for patients and their families to access and manage.
Precision leukemia therapies
By identifying specific genetic mutations through genomic testing, oncologists can determine which treatments are likely to be most effective and have the fewest side effects. Certain genetic mutations make patients less likely to respond well to cancer therapies such as tyrosine kinase inhibitors (TKIs), chemotherapy and immunotherapy that are typically the first treatments offered after diagnosis.
Other mutations make patients more likely to respond to a particular medication. For example, our team at the John Theurer Cancer Center at Hackensack Meridian Hackensack University Medical Center helped conduct a clinical trial of patients with high-risk chronic lymphocytic leukemia (CLL), in which circulating immune cells called B cells proliferate wildly. The trial compared the use of chemoimmunotherapy with a targeted therapy called ibrutinib, which blocks a protein involved with B cell growth and survival.
Patients treated with targeted therapy had a longer response resulting in sustained remission and survival, and were less likely to need a backup treatment because the initial treatment failed. The research suggests that it may be appropriate to treat some CLL patients first with a targeted therapy. It also means that clinicians have more to evaluate when selecting the best sequence of therapies to give to a leukemia patient.
Genomic testing, combined with knowledge from decades of cancer research, gives hematology/oncology specialists the ability to choose from a growing array of targeted therapies for different types of leukemia. These include midostaurin and gilteritinib, which target a faulty enzyme that causes blood cell maturation to go awry and drives acute myeloid leukemia (AML). They include tyrosine kinase inhibitors, which target the abnormal BCR-ABL1 protein that drives chronic myeloid leukemia (CML).
Targeted therapies also include chimeric antigen receptor T-cell (CAR-T) therapy, in which white blood cells are reprogrammed in the lab to target antigens on cancer cells in patients with acute lymphoblastic leukemia (ALL) and B-cell acute lymphocytic leukemia. And new medications are available to treat patients with a p53 gene mutation, which is common in many types of cancer and can present treatment challenges to patients with relapsed or refractory AML.
Social determinants of health
To further optimize leukemia treatment, oncologists are increasingly looking at the whole picture of a patient’s life — not just the disease. Some researchers are studying population health to improve cancer care. They analyze data across populations from sources like electronic health records, diagnostic results, genomic tests and hospital billing codes, with the goal of discovering factors that drive disparities in cancer risk and patient outcomes. These factors can be biological, behavioral or socioeconomic, and understanding them is the first step to addressing them to prevent cancer.
Other researchers and medical centers are addressing the social determinants of health — factors such as healthcare quality and access, education, economic stability, which neighborhood a person lives, and his or her social interactions or lack thereof. These factors, too, can be addressed to eliminate barriers to receiving the intensive therapies required to treat cancer.
For example, by analyzing data from 11,600 patients in the Surveillance Epidemiology End Results (SEER) Program of the National Cancer Institute, researchers found that African American ethnicity was the main characteristic of young patients with AML who had a poor prognosis. What’s more, not being African American was one of only two risk factors that promoted increased survival, they reported at the American Society of Hematology (ASH) 2020 virtual meeting. The results pointed to disparities in care for African American AML patients, and underscored a need to improve access to care, treatment options, and supportive services that address the social determinants of health.
Recently, Sheetal Kircher of Northwestern University Feinberg School of Medicine and her colleagues published research that showed that patients who had access to education with a financial counselor during cancer treatment showed increased physical and mental well-being. With this new awareness, oncologists across the country are taking new approaches to leukemia treatment that aim to address health disparities, while considering each patient’s unique social and economic circumstances.
Quality of life
With all the new knowledge and tools at their disposal, today’s oncologists can now focus not only on treating cancer, but also on making sure the treatment aligns with each patient’s goals and wishes for quality of life.
Better quality of life can in turn improve prognosis. As cancer research advances, tomorrow’s leukemia patients can expect even more treatment options, more effective and targeted drugs and improved well-being — all of which will help lead to better outcomes and healthier lives.
James McCloskey, MD, is Chief of the Leukemia Division at John Theurer Cancer Center at Hackensack Meridian Hackensack University Medical Center.