Memorial Sloan Kettering radiation oncologist J. Isabelle Choi

J. Isabelle Choi, MD

Radiation Oncologist

Areas of Expertise

Conditions I Treat

  • Breast cancers and conditions

My Specialties

  • Proton therapy
  • External beam radiation
  • Image-guided radiation therapy (IGRT)
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Dr. Choi's Office Information
Languages: English
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Get to Know Me

I am a radiation oncologist who has special training in the treatment of breast cancer, including early-stage breast cancer, locally advanced breast cancer, and recurrent breast cancer.

I use highly conformal photon therapy techniques and pencil beam scanning proton therapy in my clinical practice. My experience in proton therapy allows me to identify patients who may benefit from this latest type of external beam radiation therapy. Proton therapy allows for more precise delivery of radiation therapy to the tumor and helps spare healthy tissue from exposure to radiation.

When caring for patients, my goal is to achieve the best possible results. I provide empathetic, holistic care and consider each person’s priorities while creating a treatment plan. I collaborate with different experts from the oncology care team to deliver a comprehensive, evidence-based care plan.

I was drawn to cancer care after a family member was diagnosed with cancer. Throughout my academic journey, I recognized the positive impact that I could have on a patient during one of the most challenging times in their lives. This motivated me to pursue a career in radiation oncology.

My research focuses on developing new approaches to reduce treatment-related side effects, improve the delivery and use of radiation therapy for people with breast cancer, and identify ideal salvage radiation therapy strategies for breast cancer that returns. 

I am the principal investigator of a national, multicenter, prospective randomized trial that studies the use of a shorter proton therapy regimen for treating people with breast cancer. I am also the principal investigator of an institutional, prospective clinical trial studying outcomes of the use of proton therapy for the delivery of repeat radiation therapy for people with recurrent or new primary cancers.

Among my multiple national and international leadership roles, I am the Chair or co-Chair of breast cancer committees leading efforts to improve radiotherapy delivery for breast cancer through education and research, including those for the American Radium Society (ARS), Proton Collaborative Group (PCG), Particle Therapy Co-Operative Group (PTCOG), and American College of Radiation Oncology (ACRO).  

What I Do at MSK

I'm a radiation oncologist, which is a cancer doctor with special training in using radiation therapy (RT) to treat cancer.

  • Associate Attending Radiation Oncologist
Areas of Expertise

Conditions I Treat

  • Breast cancers and conditions

My Specialties

  • Proton therapy
  • External beam radiation
  • Image-guided radiation therapy (IGRT)
  • Intensity-modulated radiation therapy (IMRT)
  • Cardiothoracic imaging
Education & Honors

Education

  • MD, University of Texas (Health Science Center at San Antonio)

Residencies

  • Radiation Oncology - Kaiser Permanente, Los Angeles Medical Center

Board Certifications

  • Radiation Oncology

Awards and Honors

  • 40 under 40 Electee, Crain’s New York Business (2023)

Insurance Information

Understanding your insurance options is an important part of managing your cancer care. We have relationships with many common healthcare providers and plans.

Don't see your carrier or plan? We can help you understand your coverage.

If you don't have health insurance or are worried that your care may not be fully covered, our financial assistance programs may be able to help.

If you have questions about insurance, call us at 646-497-9176.

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Contact and Location

Office Phone
Location
New York, NY
Memorial Sloan Kettering Cancer Center
1275 York Avenue New York NY 10065
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Colleagues

Doctors at Memorial Sloan Kettering work as teams, with specialists from all different areas. This allows us to consider all your needs together, and to give you the best possible care.

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Clinical Trials

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Find a Clinical Trial for You

Memorial Sloan Kettering's doctors and scientists are constantly developing new treatments for cancer. MSK is typically running hundreds of clinical trials at a given time.

You may be able to participate in a clinical trial even if you are new to MSK. Search our online directory to find trial information and see more about who can participate.

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Research and Publications

Publications on PubMed

Visit PubMed for a full listing of Dr. Choi’s journal articles. Pubmed is an online index of research papers and other articles from the US National Library of Medicine and the National Institutes of Health.

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Disclosures

Members of the MSK Community often work with pharmaceutical, device, biotechnology, and life sciences companies, and other organizations outside of MSK, to find safe and effective cancer treatments, to improve patient care, and to educate the health care community. These activities outside of MSK further our mission, provide productive collaborations, and promote the practical application of scientific discoveries.

MSK requires doctors, faculty members, and leaders to report (“disclose”) the relationships and financial interests they have with external entities. As a commitment to transparency with our community, we make that information available to the public. Not all disclosed interests and relationships present conflicts of interest. MSK reviews all disclosed interests and relationships to assess whether a conflict of interest exists and whether formal COI management is needed.

J. Isabelle Choi discloses the following relationships and financial interests:

No disclosures meeting criteria for time period


If you’re a patient at MSK and would like more information about your doctor’s external relationships, please talk with your doctor.

The information published here is a complement to other publicly reported data and is for a specific annual disclosure period. There may be differences between information on this and other public sites as a result of different reporting periods and/or the various ways relationships and financial interests are categorized by organizations that publish such data.

This page and data include information for a specific MSK annual disclosure period (January 1, 2024 through disclosure submission in spring 2025). This data reflects interests that may or may not still exist. This data is updated annually.

Learn more about MSK’s COI policies here. For questions regarding MSK’s COI-related policies and procedures, email MSK’s Compliance Office at ecoi@mskcc.org.


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