Health Disparities and the Global Landscape of Lymphoma Care Today

The American Society of Clinical Oncology (ASCO) Annual Meeting brings together more than 30,000 oncology professionals each year to encourage discourse on leading research, state-of-the-art treatments, and ongoing controversies in the field. At this year’s Annual Meeting in Chicago, our own Dr. Adrienne Phillips was selected to present a review of the current health disparities in lymphoma care.

Adrienne Phillips

According to the National Institute on Minority Health and Health Disparities, health disparities are defined as “differences in incidence, prevalence, morbidity, mortality and burden of diseases and other adverse health conditions that exist among specific population groups.”

Dr. Phillips explained that health disparities may be due to a variety of factors, including race, gender, biology, and social and environmental differences such as socioeconomic status, health literacy, trust in the healthcare system, proximity to a healthcare facility, and access to and type of health insurance. For example, being uninsured or receiving government-assisted insurance increases patients’ risk of death by 1.5 times. Even patients’ place of residence may play a role, with treatment in rural, community-based settings being associated with inferior overall survival (OS) rates compared to treatment in urban, academic-based settings.

What Dr. Phillips and other physicians find most disconcerting about disparity in lymphoma care is that the disease is often amenable to effective therapy, but a significant segment of the population does not, or cannot, access appropriate care. For example, survival rates for some lymphomas skew lower for black people than for white people. Dr. Phillips conjectured that while African Americans tend to have poorer outcomes, the disparity is likely due to issues related to healthcare access and socioeconomic status.

According to an analysis of 701 people with diffuse large B-cell lymphoma (DLBCL) treated at two southern referral centers with a large black patient population (University of Alabama at Birmingham and Emory University in Atlanta), race did not influence outcomes. Black and white patients who received standard DLBCL chemotherapy drug combination rituximab, cyclophosphamide, doxorubicin hydrochloride, vincristine sulfate, and prednisone (R-CHOP) achieved similar OS rates (5y OS, 79% vs 70%).

Biological factors may also play a role in health disparities, and scientists are constantly working to better understand molecular factors in tumor development regardless of patient ethnicity.

In general, lymphoma is less common among African Americans and Asian Americans, but specific subtypes – like T-cell lymphoma in African Americans and natural killer T-cell (NKT) lymphoma in Asian Americans – are more common in these populations. Thus, Dr. Phillips highlighted a need for ethnic and racial diversity in clinical trial recruitment and in future studies of socioeconomic status and disease biology in order to better understand and improve outcomes for all patients.

Dr. Peter Martin Calls for Consideration of Patient Preference in Mantle Cell Lymphoma Treatment

SOSS_Peter_Martin3 (1)Citing a pattern of intensive mantle cell lymphoma (MCL) treatment regimens, Dr. Peter Martin – who co-chaired the OncLive State of the Science Summit on May 4, 2017, along with Dr. John Leonard – proposed that physician-researchers become more mindful of patient preferences when determining treatment regimens. He noted that some patients might prefer to receive more broadly accessible treatments and that those decisions may not significantly impact outcomes.

High-dose cytarabine followed by an autologous stem cell transplant, for example, is an effective treatment regimen for patients with MCL, at times inducing remission durations of 10 years. But people with MCL, who tend to be in their mid-sixties, are rarely keen to take the requisite six months away from work in order to receive treatment. Because fewer than 25 percent of MCL patients are eligible for intensive regimens, more practical treatment strategies are needed.

Dr. Martin also stressed the need to find a way to help patients who are destined to have poorer outcomes due to the presence of multiple risk factors as defined in the combined Mantle Cell Lymphoma International Prognostic Index (MIPIc). These factors include: age, white blood cell count, performance status, lactate dehydrogenase (LDH), and Ki67, a marker of tumor cell proliferation.

In a comparison of two clinical trials from the European Mantle Cell Lymphoma Network, one in which patients less than 65 years of age were treated intensively with an autologous stem cell transplant, and another wherein a set of older patients received R-CHOP or fludarabine-based therapy followed by rituximab maintenance, Dr. Martin pointed out that patients with similar MIPIc scores had similar outcomes no matter their treatment regimen.

Dr. Martin highlighted that multiple clinical trials are underway to determine the best drug to combine with the MCL treatment backbone of bendamustine rituximab, to investigate ibrutinib combinations in the relapsed setting, and to evaluate the necessity of intensive treatments like stem cell transplantation.

Watch this OncLive clip for more of Dr. Martin’s thoughts on patient preference:

Dr. John Leonard Comments on CAR T-Cell Therapy Outlook

Dr. John Leonard at State of the Science SummitChimeric antigen receptor (CAR) T-cell therapy is an emerging form of immunotherapy that leverages the strength of a patient’s own immune system to fight cancer.

Immune cells called T-cells are extracted from the patient’s blood and modified in the laboratory to produce chimeric antigen receptors, surface-level proteins that enable the T-cells to recognize and fight targeted antigenic tumor cells. The newly engineered T-cells are then cultivated in a lab before infusion back into the patient’s body, where they further multiply and go to work attacking cells that possess the antigen that they were programmed to destroy.

At the OncLive State of the Science Summit on Treatment of Hematologic Malignancies, Dr. John Leonard, who served as co-chair for the May 4 event, expressed promise in the use of CAR T-cell therapy for patients with acute lymphoblastic leukemia (ALL), in particular.

Dr. Leonard said that in a small group of clinical trial recipients with ALL, the immunotherapy has produced excellent, seemingly durable responses, and more data on CAR T-cells for patients with hard-to-treat lymphomas, like resistant forms of diffuse large B-cell lymphoma (DLBCL), are forthcoming.

While patient selection is a crucial part of interpreting the data and planning for the future, Dr. Leonard believes that the main challenges in the development of CAR T-cell therapy relate to factors of patient selection such age, comorbidities, and aggressive cancers with prohibitive wait times for engineered cells, which can take as long as several weeks depending on the specific CAR product being used.

 “I think there’s no doubt that some patients benefit, but at least in the near-term, it’s going to be a relatively small number of patients that will get CAR T-cells for lymphoma,” he said.

Check out what else Dr. Leonard had to say about CAR T-cells in this video from OncLive: