A Personal Remembrance: Dr. Marc L. Citron

A Personal Remembrance: Dr. Marc L. Citron

Clifford A. Hudis, MD, FASCO, FACP

Mar 19, 2021

Along with his friends, family, and patients, I was saddened to learn that longtime ASCO member Marc L. Citron, MD, died of a recurrent glioblastoma on Thursday, February 25, 2021, at home with his loved ones at his side.

Marc lived methodically and planned his passing similarly. A friend and colleague, Dr. Maria Theodoulou, described the way Marc arranged his funeral and his affairs as a “gift,” because it freed everyone to focus on supporting one another and celebrating his life without the distraction of guessing about his wishes or having to address loose ends. Marc had already taken care of everything.

The last phone call Marc had was with ASCO past president Larry Norton, MD. There are probably several reasons this call happened that way, but I want to focus on the unifying themes: career, collaboration, contribution, and connection. Marc spun these together into a life of giving, laughing, and loving.

From the ASCO perspective, Marc was everything we hope for in a member. Born in Detroit, he was well-educated, earning his MD at Wayne State and training in medical oncology at Georgetown University. He conducted laboratory research early in his career and then moved to full-time clinical practice and teaching. He served as the division chair of oncological services and director of cancer services at ProHEALTH Care Associates and as a clinical professor of medicine at Hofstra North Shore LIJ School of Medicine, but, despite these administrative and clinical responsibilities, he maintained a passionate commitment to research and was a prominent member of the Breast Committee of the Cancer and Leukemia Group B (CALGB, now the Alliance for Clinical Trials in Oncology—one of the main NCI-supported cooperative groups).

I came to know Marc through his engagement with the New York Metropolitan Breast Cancer Group and the CALGB. As a young faculty member at Memorial Sloan Kettering Cancer Center, I had the opportunity to lead phase II studies using granulocyte-colony stimulating factor to shorten the interval between conventionally dosed adjuvant chemotherapy cycles. This enabled us to convert my mentor’s (Larry Norton) mathematical models of tumor growth and chemotherapy response into feasible “dose-dense” adjuvant treatment regimens for breast (and other) cancers.

As the Breast Committee of the CALGB designed the definitive comparative (phase III) trial that would test dose-dense therapy, the leadership (Drs. Larry Norton and Hy Muss) sought a meticulous investigator to serve as principal investigator. Marc was that and so much more. He also represented an often-overlooked constituency—community practitioners—and that made him unusual alongside the typical academic investigators leading most large randomized trials. This trial (called “C9741”—the 41st CALGB trial of 1997) accrued rapidly and changed the standard of care for high-risk, early-stage breast cancer. 

I was fortunate to work with Marc as the study accrued and the results were analyzed. The study definitively showed that dose-dense therapy was superior, and it propelled a humble Dr. Citron to the podium at the 2002 San Antonio Breast Cancer Symposium, where he delivered practice-changing results. His publication in ASCO’s Journal of Clinical Oncology just a few months later in 2003 remains heavily cited.1

As a colleague, Marc was always grateful, gracious, and generous with his time. He was thoughtful, considerate, and, most of all, obsessively devoted to the well-being of his patients. An email or call from Marc always meant that he had identified a challenging and subtle issue that went beyond the known literature and evidence. What struck me was that his questions were always driven not by abstract or theoretic concerns but instead were the result of his obsession with delivering the best possible care to every patient every day. Coupling that drive with personal humility and openness strikes me as an ideal recipe for a great doctor.

Our core values at ASCO are evidence, care, and impact. The starting point—Evidence—is built on research, and Marc shared and embodied our passion for creating it and then using it to improve patients’ lives. Over the last few years, as he saw that his time was limited, he reached out to Conquer Cancer, the ASCO Foundation, to ensure ongoing research support for investigators focused on breast cancer, his career-long area of special interest. Thanks to him and his supporters, we will award the Marc L. Citron, MD Career Development Award in Breast Cancer and three Marc L. Citron, MD Young Investigator Awards in Breast Cancer in the next few years.

As I noted, Marc was a model ASCO member—researcher, educator, and caring clinician—but more than that, he showed our entire community how to be a caring colleague, dedicated clinician, and collaborative researcher. He was also devoted to his community and his family, and, through everything, he was simply nice to everyone!

I hope we can collectively pause, reflect on a life so well-lived, and find strength and inspiration from his example. At his funeral, conducted remotely, his lifelong friend Dr. Samuel A. Berkman spoke about their decades of adventures, mostly centered around family and career. He recounted that just a few days before he passed, Marc had joked that the pastry he was enjoying at that moment “was to die for.” The story captured the themes and lessons of Marc’s life: embrace, enjoy, and celebrate what is good, make the best of what is not so good, and take care of everyone with as much good humor as you can.

Along with his wife, Chris Citron, children Leah Dembitzer, Evan Citron, and Adam Citron, his devoted patients, and his friends and colleagues, I will always miss Marc L. Citron, MD, remember his contributions, and try to live up to his example.


  1. Citron ML, Berry DA, Cirrincione C, et al. Randomized trial of dose-dense versus conventionally scheduled and sequential versus concurrent combination chemotherapy as postoperative adjuvant treatment of node-positive primary breast cancer: first report of intergroup trial C9741/Cancer and Leukemia Group B trial 9741. J Clin Oncol. 2003;21:1431-9.



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Joseph A. Sparano, MD

Mar, 19 2021 5:22 PM

A great loss to our community, and to humanity. I was inspired by his courage as he faced this by freely sharing his diagnosis and struggles with friends, colleagues, and patients alike.

Juan G. Posada, MD

Apr, 07 2021 1:38 PM

I met Mark in Washington D.C. in 1983  after  we both completed our Fellowship in medical oncolgy in Georgetown ,at the Vincent T. Lombardi Cancer Center. He then work at the Washington D.C . VA  where we met few times for lectures , and rounds  before he headed back  to NY . 

I vividly remenber  a joke he used to tell constantly before  his lecures . He was making rounds.  one day in the wards  at Long Island Jewish  Hospital  on an elderly lady who was  in Atrial Fibrilation  and  he spoke to the resident about convering her to Sinus Rhythn ,  the elderly lady  only heard  "converting"   ,and suddenly woke up and said   " I have been a catholic all my life  and nobody is convering  me  now " ,

I saw Mark at the ASCO mettings   and was  impressed when he published the Dose Dense Adjuvant Chemotherapy in the JCO , I bragged that Iknew him  and we trained at the same place . He was indeed kind  and a great colleague  and set a great example for  many including me .  I am  very saddend  about his dead . My deepest condolances and prayers are with  his family  ,  

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