Rex Hoffman, M.D., MBA, chief medical officer of Providence Holy Cross Medical Center, discusses his transition from radiation oncologist to hospital executive and the panel discussion that led to his new book, “Difficult Dilemmas for Chief Medical Officers: 30 Case Studies.”
In this interview, Rex Hoffman, chief medical officer of Providence Holy Cross Medical Center in Mission Hills, California, describes his path from practicing radiation oncologist to hospital executive. Hoffman also discusses his work creating Providence’s first Chief Medical Officer Handbook as well as his newest book, “Difficult Dilemmas for Chief Medical Officers: 30 Case Studies.” Looking ahead to his first Health System Executive Summit, he said he hopes to bring back insights on dyslipidemia management, the 340B landscape, pediatric vaccination and community-based CAR-T programs.
This interview has been edited for length and clarity.
MHE: To begin, would you please introduce yourself and provide an overview of your role at Providence Holy Cross Medical Center?
Hoffman: My name is Rex Hoffman, and I am the Chief Medical Officer of Province Holy Cross Medical Center in Mission Hills, CA, and in this role my main job is really to act as the liaison between the medical staff and hospital administration at Province Holy Cross.
MHE: How did you go from frontline physician to chief medical officer?
Hoffman: I worked clinically as a radiation oncologist from 2001 to 2019, and in the latter years I started taking on more and more leadership responsibilities both at the hospital I was working at and in the larger health system of Providence.
Ultimately, I became the co-chair of the Cancer Institute for the entire health system. In this role I found myself at the table with the Chief Financial Officer and Treasurer of Providence Health System negotiating a large deal to secure a bulk purchase of linear accelerators that were subsequently deployed across 5 states and 12 departments.
It was during this time that I realized my Achilles heel was my lack of knowledge in the business of medicine, and so I enrolled in the Indiana University Kelley School of Business and Medicine program in 2016, which I subsequently graduated from in 2018.
During the time I was in that program, I met one of my classmates, who was a chief medical officer in Michigan, and after hearing about his day-to-day responsibilities, I decided that I too wanted to become chief medical officer.
Six months after graduating from the Kelley School of Business, I became the Chief Medical Officer at Province Holy Cross, a position I'm still in today.
MHE: Has your work as a chief medical officer been restricted to your medical career?
Hoffman: Actually, no.
I've been chief medical officer at Province Holy Cross for 7 1/2 years, and during this time I've held other responsibilities as well.
I started as chief medical officer at Holy Cross in 2019.
From 2020 to 2022, I was the chief medical officer, a clinical leader of eight clinical institutes across 11 hospitals and provinces in the Southern California region.
These clinical institutes included cancer, cardiovascular, digestive health, mental health, neurosciences, orthopedic, spine research, and women's and children's.
In 2022, I then came back full-time to Province Holy Cross, where, in addition to working as Chief Medical Officer, I also worked as the Executive Director of Operations, where I had oversight over all the Ansley departments at the Medical Center, including such departments as Imaging, Lab, Food, Nutrition, Pharmacy and others.
In 2025, I was then asked to help two sister hospitals that were looking for new chief medical officers.
So, from January through July of 2025, I worked as the interim chief medical officer at Providence Cedars-Sinai Tarzana Medical Center until they found the permanent replacement.
And then the next five months, from August through December 2025, I worked as Interim Chief Medical Officer at Province St.
Joseph's Medical Center in Burbank until they too found a permanent replacement.
Today I am back at Holy Cross full-time as the Chief Medical Officer and currently the Interim Executive Director of Operations until we fill that role.
MHE: Your new book is called “Difficult Dilemmas for Chief Medical Officers: 30 Case Studies.” What led you to write this book?
Hoffman: As chief medical officers, we all deal with difficult dilemmas in our normal daily work.
And so I had the idea of creating a panel at the American Association of Physician Leadership annual meeting in 2025 entitled Difficult Dilemmas for Chief Medical Officers.
I served as the moderator and had four panelists that were all chief medical officers.
And what I did was I posed each one of them with two different difficult dilemmas, and in front of the audience, they quickly unraveled the dilemmas and shared with the audience, based on their experience, how they would address these particular cases.
At the conclusion of this panel, it was so successful that several members of the audience as well as a couple of the panelists themselves suggest I write a book on it.
And so subsequently, the book was born.
MHE: Is this your first book?
Hoffman: It’s not. Two years after I became a chief medical officer, I was surprised there was no real formal onboarding process for chief medical officers at Providence Health System.
When I saw that there were over 50 hospitals across Providence, I quickly collaborated with 30 chief medical officers across the entire health system to create the first official Chief Medical Officer Handbook, which is now given to each new chief medical officer at Providence Health System.
About six months later, I received a call from two chief medical officers on the East Coast, one of whom was Mark D. Olszyk, M.D., MBA, CPE, Chief Medical Officer and Vice President of Medical Affairs at Carroll Hospital, in Maryland. Mark was working on a book called “The Essential Guidebook for Chief Medical Officers.” Nothing of its kind had ever been created before. I subsequently became a co-author on this book.
While we were promoting this book, I noticed there were some chief medical officers in the audience, and there were several physicians aspiring to be chief medical officers, and so I wrote a book called “I Want to Be a Chief Medical Officer: Now What?”
MHE: As you look ahead to your first Health System Executive Summit, what about this gathering stands out to you, and what are you hoping to bring back to Providence from the conversations and connections you expect to have?
Hoffman: I am very much looking forward to this summit after hearing the great lineup of speakers and the key topics that will be covered.
The agenda includes topics such as advances in managing dyslipidemia, current challenges in the 340 B landscape, current and future advances of vaccinations, particularly in children, and then key considerations of CAR-T treatment programs in community settings.
I know as a chief medical officer, each of these areas is one that I need to address in my health system, so I look forward to gleaning some pearls of wisdom and bringing them back to my health system.
