Many people have a connection to blood cancer. It’s likely you know someone whose life has been impacted by a disease such as leukemia or non-Hodgkin’s lymphoma (NHL). These are among the most common cancers in the United States and, altogether, more than a million people in the country are living with or in remission from a blood cancer.
The good news is that advances in screening, imaging, and treatment have changed the outlook for many people with blood cancers. Some diseases, once considered fatal, can potentially be managed for years. However, not all blood cancers have been equally impacted, and there’s still a significant need for more progress.
We’ve learned a lot in recent years, and here are three essential insights to consider as we look to continue to help people with blood cancer.
1. Every blood cancer—and patient—is unique
Blood cancers like NHL are often talked about in a general way that doesn’t reflect their incredible diversity. In reality, “blood cancer” is an umbrella term that includes more than 80 unique diseases—and counting. These classifications are more than details in a textbook—they provide crucial information to doctors to understand the disease and help guide treatment decisions.
The three basic categories are leukemias, lymphomas, and myelomas—defined based on where the cancer originated. Within each of these categories, the breakdown of subtypes has become progressively more granular, driven by increased understanding of disease biology.
Lymphoma is a prime example. This term refers to cancers originating in the lymphatic system. Clinical classification began in the mid-1800’s after British doctor Thomas Hodgkin published a description of what became known as Hodgkin’s lymphoma. All other lymphomas were then lumped into the catch-all “non-Hodgkin’s lymphoma.”
Today, NHL is divided broadly into slow-growing (indolent) and aggressive diseases. More detailed subtypes are defined by factors like cell type, clinical characteristics, and genetic abnormalities. Well-known NHL subtypes include follicular lymphoma (the most common indolent NHL), diffuse large B-cell lymphoma (DLBCL, the most common aggressive NHL), mantle cell lymphoma, and Burkitt lymphoma.
Each type of blood cancer is treated in a different way. For example, patients with DLBCL are typically treated immediately, while for some follicular lymphoma patients, treatment may be delayed until the disease causes more significant symptoms (a “watch and wait” approach).
The patient experience also varies widely, and not just based on blood cancer type. Factors like coexisting medical conditions, genetics, and responses to previous therapies can all impact a person’s prognosis, treatment options, and experience with their disease. Truly every case is different. So it’s imperative that doctors work with each patient to chart their own individual plan.
2. We’re in the midst of a shifting treatment landscape
This is an incredibly exciting time in the field of blood cancer. Decades of research have culminated in a wave of new treatment options, and, as a result, more people are living longer past their initial diagnosis.
Earlier treatments for blood cancers—chemotherapy, radiation, and bone marrow transplants—helped make some patients’ disease go into remission, but incidence and mortality continued to rise. Then, the tide began to turn in the late 1990’s when the era of targeted therapy in blood cancer arrived.
These treatments helped many patients, but additional options were still needed. Researchers continued to push forward and these efforts are now bearing fruit.
This is evident in the U.S. Food and Drug Administration’s (FDA’s) Breakthrough Therapy Designation, a program created to expedite development of promising new medicines for diseases with high unmet medical need. Of the breakthrough designations publicly announced since the program’s inception in 2012, 23 were for investigational medicines for blood cancer—more than any other disease area. As a result, nearly a dozen new blood cancer medicines have received FDA approval under this program.
Results presented at conferences like the American Society of Hematology (ASH) annual meeting hint at more potential advances to come, including data in specific blood cancers where progress has historically lagged behind. For example, some chronic lymphocytic leukemia (CLL) treatments are focused on people with genetic changes linked to a poorer prognosis. New investigational treatments may finally provide additional options for people with acute myelogenous leukemia (AML), a disease that’s seen no significant changes in treatment beyond chemotherapy in nearly 40 years.
3. The questions we need to ask are changing
The field of blood cancer today is quite different than it was even just a few years ago. With all this recent change, it’s crucial to continually reassess our approach and make sure we’re asking the right questions.
How should new medicines be evaluated?
Every new medicine must go through rigorous clinical trials to ensure safety and efficacy. The traditional “gold standard” endpoint in cancer clinical trials is overall survival (OS). However, as people live longer, it’s increasingly difficult to assess OS within the limited time window of a clinical trial.
To evaluate efficacy and safety in a timely manner—and potentially get new medicines to patients more quickly—researchers are turning to surrogate endpoints that may predict clinical benefit but can usually be measured sooner. These data are the key to the FDA’s Accelerated Approval program, which grants conditional approval for medicines based on surrogate endpoints. Confirmatory trials are required, as surrogate endpoints may not always be true indicators or signs of how well a treatment works.
A common surrogate endpoint in blood cancer is progression-free survival (PFS), a measure of the time a person lives without their disease worsening. Response rates, defined in part by a decrease in the number of cancer cells, are also commonly used.
More recently, a new potential surrogate endpoint is being evaluated: minimal residual disease (MRD) status. Using highly sensitive technologies, MRD testing can detect trace amounts of disease that persist even when standard tests come back clean (MRD testing can identify 1 cancer cell in 10,000 normal cells, whereas traditional tests can detect only about 1 in 100 cells). Some evidence suggests that MRD-negativity after treatment may predict longer PFS or even OS in diseases such as CLL.
How do we use the many new available treatments?
Medicines in the current treatment landscape include chemotherapies, antibodies, and oral medications. Promising new therapies for patients with unmet need are arriving faster than ever thanks to expedited pathways like breakthrough designation and accelerated approval. With so many new options available, large clinical trials directly comparing treatments (head-to-head studies) will be important to determine the relative efficacy and safety of different medicines, or combination of medicines, in specific patient populations.
Additional studies are also necessary to determine the optimal sequence of therapies. The choice of initial (first-line) treatment may be especially important in indolent blood cancers where the prognosis gets worse with each relapse. The first-line setting may provide an opportunity to impact the course of the disease, potentially providing longer remission and treatment-free periods. In the relapsed setting, there’s significant unmet need for treatments that are effective in people who have developed resistance to existing targeted therapies.
How can we support the growing population of blood cancer survivors?
As the number of blood cancer survivors continues to grow, we’re faced with the new challenges of addressing their long-term needs.
Quality of life can be a key consideration. For many people, it’s important to not just live longer, but to also live well. Regulatory authorities like the FDA have recognized this and are working with industry and doctors to potentially incorporate patient-reported outcomes into clinical trials and product labels.
For blood cancers, in particular, a person’s experience can be impacted by their treatment. How is the medicine delivered? What are the side effects? Is treatment given indefinitely or is a treatment-free period possible? Having more options has enabled patients to ask these questions as part of developing a treatment plan.
Finally, we must recognize that the effects of cancer are not just physical, but mental too. Survivors often face lingering anxiety or depression, and long-term support is crucial. Patient advocacy groups like the Lymphoma Research Foundation, Leukemia and Lymphoma Society, and CancerCare are dedicated to helping blood cancer survivors feel supported, connected and engaged.
This is an exciting era for patients, clinicians, and researchers. Now is the time to turn the lessons of recent years into insights that help people with blood cancer, and build a future in which patients can look forward to not just surviving but thriving as long as possible.