Arguing for Better Leukemia Care

Susan M. O’Brien, MD

Susan M. O’Brien, MD, always knew medicine was the field for her. Growing up in a house full of bankers and finance-oriented family members couldn’t deter her from her chosen path.

O’Brien, the oldest of 6, said that having to hold her own in family arguments instilled in her strong convictions and the willingness to defend her positions at a young age, and she has used those lessons throughout her career.

Although medicine was always at the core of her plan, the specifics of that journey were far from clear. “Like anybody who starts out, I wasn’t really sure what I wanted to do in terms of where I wanted to go with medicine,” explained O’Brien, associate director for clinical science at the Chao Family Comprehensive Cancer Center and medical director at the Sue and Ralph Stern Center for Clinical Trials and Research at the University of California, Irvine (UC Irvine).

O’Brien received her bachelor’s degree in biochemistry from Mount Holyoke College in South Hadley, Massachusetts, and her medical degree from Rutgers Biomedical and Health Sciences (formerly the University of Medicine and Dentistry of New Jersey). Although her schooling was a straightforward decision, choosing her specialty was a slower process.

She knew she was “too clumsy” for surgery and she wasn’t interested in pediatrics or obstetrics and gynecology, so oncology rose to the top of her list. Oncology research was not fully established when she began her career in the early 80s and joining a relatively young field appealed to her. More significantly, her mother died of lung cancer at age 50, and the loss profoundly affected O’Brien.

“It was very sad because, obviously, she was so young but also because she had spent her whole life raising all these children, and now they were all going off to school and she was going to really get to sit back and enjoy her life a little bit more,” she said.

A bit of luck and good timing landed O’Brien in the field she ultimately would choose. Her first fellowship rotation was leukemia, and she realized that this area was her calling. “I don’t know whether it was because it was the first one or I really would have been destined to do that, but I just really, really found the disease fascinating,” she said.

Motivated by her mother’s death and supported by family members and mentors, O’Brien would go on to reshape the then-underdeveloped field of leukemia.

Bringing Leukemia Treatment into the Future

As a child, O’Brien lived in Manhattan, New York, until her family moved to New Jersey when she was 10. The family’s penchant for spirited debate came with them. She and her siblings battled over pretty much any issue, O’Brien said, with fights being less about who had the last word and more about delivering a sharp and cogent point. Had she not been set on medicine from an early age, O’Brien said, she would be equipped to be a successful lawyer: “If you said something, you’d better be sure you were right, or somebody was going to question you.”

Those heated discussions later helped her navigate the “testosterone-laden place” that is the field of leukemia, she said. O’Brien is grateful she grew up in that environment, which she believes prepared her to navigate not only the male-dominated field of medicine but also society as a whole.

“When I started out, there were very few women,” she said. “Growing up in that kind of a family really helped me develop the personality where the vagaries of trying to get ahead in oncology were easier for me because of the strong personality I developed in childhood...I was able to get through the difficulties of having very few women around.”

Although her family background prepared her to handle a male-dominated field, it was her mentors at The University of Texas MD Anderson Cancer Center in Houston who showed her she could thrive. Hagop M. Kantarjian, MD, and Michael J. Keating, MBBS, both past Giants of Cancer Care® award winners, helped O’Brien push the limits of leukemia treatment.

“My mentors were very open-minded, and they were able to think outside the box,” she said. “In the early days of leukemia, when outcomes were very poor, I think that was crucial to making the field move forward, because you had to think outside the box if you were ever going to come up with new therapies for people.”

Kantarjian and Keating also refused to take no for an answer, and they helped move the field of leukemia toward new standards alongside O’Brien. This mind-set resonated with her; it aligned with the lessons of her upbringing, in which unsubstantiated claims got you nowhere.

“In one sense it was very much like my family,” she said. “You could try any idea you wanted no matter how unusual it sounded, but you needed a rationale for why you wanted to do something.”

That dynamic, coupled with her own resolve to save lives, drove O’Brien to change the standard of care. Her mentors showed her that, as long as she could provide sound reasoning and evidence, she could be as creative as necessary. “They were visionary people who always tried to look beyond where we were and what the next possible step was,” she said. “That’s very impactful on somebody, particularly when they’re young and they’re training.”

Fast-forward to today and she has emerged as a leading figure in the leukemia space. Over the past decade, she has challenged the longtime standard of care for leukemia. O’Brien looked beyond chemotherapy and became involved in the development of almost every new drug for chronic lymphocytic leukemia (CLL), including ibrutinib (Imbruvica). The tyrosine kinase inhibitor has been the most widely used medication to treat patients with CLL since the FDA granted it accelerated approval in 2014.

She has served as the principal investigator for more than 40 funded clinical protocols and authored more than 900 articles in peer-reviewed journals, along with numerous book chapters and abstracts. She also has served as chair of the National Comprehensive Cancer Network guidelines panel on chronic myeloid leukemia.

“When what you’re calling your standard of care doesn’t cure most people or provide a long life span, then there’s a problem with that standard of care,” O’Brien said. “What it really means is that’s all we have right now, so we’ve got to find something better.”

That passion to save lives and always find something better for the patient has been a consistent motivator for O’Brien. She wouldn’t take no for an answer until it was proved beyond a doubt, a determination she carried throughout her life.

Finding Inspiration in Location

O’Brien also had her eyes opened outside MD Anderson. Texas, the state where she would live most of her life, was unlike anywhere she had been before. A radio broadcast reminding listeners that a “shotgun works real well” to deal with armadillos on the lawn introduced her to a world very different from what she experienced on the East Coast and in the Southwest early in her tenure.

O’Brien had plenty of opportunities to continue her training on the East Coast, so the decision to pursue her fellowship at MD Anderson surprised many people, including herself. But a change is as good as a rest, as the saying goes. O’Brien grew to enjoy the difference in scenery, especially because, starting with the interview process, she recognized the potential at MD Anderson; as she pursued her fellowship, she saw just how exciting and innovative the organization is.

“On both the faculty side as well as nursing and support staff side, there’s just this huge dedication to doing what’s best for the patient that I was impressed with right from the beginning,” she said.

It’s safe to say O’Brien is happy with her decision; she said her tenure at MD Anderson made her career as an oncologist. While there, she conducted almost all her clinical research, including the development of ibrutinib for CLL and several new drugs for the treatment of acute lymphocytic leukemia.

After almost 30 years at MD Anderson, O’Brien took the role of associate director for clinical science at the Chao Family Comprehensive Cancer Center at UC Irvine.

“A lot of what I do now is more administrative,” she said. “It’s changed quite a bit in the past couple of years. My great love, however, is clinical research.” She retains that strong will to advance the field of leukemia to new heights.

Family, mentors, and top-notch institutions have all played a role in O’Brien’s career, but her inherent drive to be better helped her revolutionize the way leukemia is treated. Despite the vast improvements care, she is even more excited about what lies ahead. She predicts that the explosion of targeted agents in leukemia will continue at an even more dizzying pace. The FDA approved 7 new drugs for CLL over the past 10 years compared with 6 during the 30 years prior.

“I expect [investigators] to continue to keep going that quickly, which is really exciting,” she said. “I think we’re going to have more and more advances and be able to cure more and more diseases that, for many years, we were unable to cure.”

If O’Brien is involved in the field of leukemia for the next 10 years, no doubt the pace will pick up even faster.