Weill Cornell’s Leonard Noted for His ASH List, Patient Care

John Leonard, MD, of Weill Cornell Medicine, New York City, has built a devoted following for his “Leonard List” — previews of research to be presented at annual American Society of Hematology (ASH) meetings that are held every December.

For example, in November 2024, in the days leading up to ASH 2025, a #leonardlist tweet that he sent out regarding an ASH abstract about research on Stage I-II pulmonary mucosa-associated lymphoid tissue lymphoma drew more than 16,000 views on the social media platform X. In December, Leonard’s tweet about outcomes in early relapse of follicular lymphoma (FL) vs early histologic transformation after first line immunochemotherapy for FL drew more than 5000 views.

Other tweets from the most recent Leonard List drew more than 2000 views. Since 2018, Leonard also has produced an annual Leonard List episode of Weill Cornell’s Cancer Cast podcast, offering his take on major cutting-edge research.

As a senior associate dean for Innovation and Initiatives at Weill Cornell, Leonard is deeply interested in efforts to move discoveries toward the marketplace.

“While it’s great to write papers and get grants and obviously very important to help individual patients that you see in your practice or in your community, large-scale impact on society really comes from taking medical knowledge and in one way or another…partnering with industry so that it gets scaled up,” he said.

Throughout his career, Leonard has published prolifically. In 2024, he authored 11 articles that appeared in peer-reviewed publications including The New England Journal of Medicine. Last February in Blood, Leonard and coauthors contributed a review of expected advances in managing FL. In it, they said they felt encouraged about the outlook for newer therapies such as chimeric antigen receptor T-cell therapy and bispecific monoclonal antibodies to eventually allow for “remissions long enough to be considered curative though such statements at present are premature.” 

“Evolution of combination approaches and dosing strategy updates may further this progress and make the elusive promise of curing FL closer to becoming a reality,” they wrote.

Even with recent advances, chemotherapy still remains a commonly used treatment in lymphoma, Leonard told Medscape Medical News in an interview.

“It can be curative for many patients, depending on the situation,” he said. “So we haven’t gotten away from old standbys, but I think we’ve either made it better or swapped in for it or given new options to people where the standard approaches did not work as well or stopped working,” he said.

Leonard’s career as an oncologist began in the mid-1990s, a time when treatments for hematologic disease were about to experience a profound shift.

“Antibodies were just coming onto the scene,” Leonard noted.

In 1997, the US Food and Drug Administration granted the first approval of a monoclonal antibody for use in cancer, clearing rituximab for use in relapsed or refractory low-grade or follicular, B cell non-Hodgkin’s lymphoma. This marked the beginning of a new wave of treatments designed to spark the immune system to target cancer in the body.

“Now, obviously, monoclonal antibodies are used across the spectrum of cancer,” Leonard said.

While he maintains a strong interest in research, especially that involving experimental drugs, Leonard also is well known for his bedside manner.

For example, he will inquire about what sports teams a patient follows, seeking a topic on which they might have a bond — or a reason for banter.

“If you love the same sports team, you sit there and commiserate — or you give each other a hard time” if the patient is a Yankees fan, Leonard commented in a Weill Cornell video about patient care. “It builds that relationship a little bit differently than just sitting there talking about what the CAT scan looks like or how the treatment’s going.”

Leonard said he became a Mets fan as an adult, adopting a team supported by his wife and her family. He grew up in northern Virginia as a fan of the Baltimore Orioles. A graduate of Johns Hopkins University, Baltimore, Leonard completed his MD at University of Virginia School of Medicine, Charlottesville, Virginia. He then moved to New York for training and has remained there since.

In 2018, the Lymphoma Research Foundation compiled a video of interviews with Leonard’s patients and played it as a tribute at its gala dinner, where the group presented him with a distinguished service award.

Concert pianist Horacio Gutiérrez, who was among the patients interviewed, said watching that video was a revelation. The noted musician spoke warmly on the video of care he received from Leonard following his 2007 diagnosis of gastric lymphoma.

As a patient, Gutiérrez appreciated the concern Leonard showed. He made an effort to spare the concert pianist being treatment with a drug considered likely to cause numbness and tingling in the fingers.

Gutiérrez has performed at New York’s Carnegie Hall and Avery Fisher Hall as well as noted venues across the United States and in Europe. Gutiérrez also has been widely recorded. In 1992, he was nominated for a Grammy for best classical performance-instrumental solowith orchestra for his recording of Rachmaninoff piano concertos.

When undergoing treatment for his lymphoma, Gutiérrez thought he was getting special treatment from Leonard due to his accomplishments and fame as a musician. The oncologist made himself available to answer questions quickly during treatment, and Gutiérrez thought he might be getting special consideration.

But at the awards banquet, Gutiérrez learned that many of the patients gathered there also thought they received extraordinary care and attention from Leonard.

“Everybody felt like they were the biggest, special patient,” Gutiérrez noted. “And I thought, ‘Isn’t that something incredible? He made everybody feel just the same.’”

Kerry Dooley Young is a freelance journalist based in Washington, DC. She has reported on medical research and health policy for more than 20 years.