
Simon N. Powell, MD, PhD, FRCP
Radiation Oncologist
Titles
Chair, Department of Radiation Oncology; Enid A. Haupt Chair in Radiation Oncology
Clinical Expertise
Radiation Oncology; Breast Cancer
We post reviews for MSK healthcare providers who have at least 30 patient experience surveys completed. If you do not see reviews for a provider, it may be because they do not yet have enough survey responses, or the provider may not be part of the group of healthcare providers included in the survey.
Only outpatient providers are included in the survey. Healthcare providers who only work in the hospital or in urgent care are not included in the survey. Pathologists or researchers who do not provide direct care to patients do not have reviews.
New Patient Appointments
Scheduling a visit is easy. Click below or call us to get started.
Dr. Powell accepts the following list of insurance providers. Select your insurance provider to see more details.
Payor Type: Commercial
In Network Coverage Type(s): HMO, EPO PPO, POS, Transplant
Payor Type:
In Network Coverage Type(s): PPO
Payor Type: Commercial
In Network Coverage Type(s): HMO, PPO
Payor Type: Commercial
In Network Coverage Type(s): PPO, POS, EPO, HMO
Payor Type: Commercial
In Network Coverage Type(s): HMO, EPO PPO, POS
Payor Type: Medicaid/Managed Medicaid
In Network Coverage Type(s): HMO
Payor Type: Commercial
In Network Coverage Type(s): Supplemental
Payor Type: Commercial
In Network Coverage Type(s): PPO, POS, HMO
Payor Type: Commercial
In Network Coverage Type(s): POS, EPO, HMO
Payor Type: Commercial
In Network Coverage Type(s): PPO, POS, EPO, HMO
Payor Type: Medicaid/Managed Medicaid
In Network Coverage Type(s): HMO
Payor Type:
In Network Coverage Type(s): PPO, HMO
Payor Type:
In Network Coverage Type(s): PPO, HMO, DSN
Payor Type: Medicaid/Managed Medicaid
In Network Coverage Type(s): HMO
Payor Type: Commercial
In Network Coverage Type(s): PPO
Payor Type: Commercial
In Network Coverage Type(s): HMO, EPO
Payor Type: Medicaid/Managed Medicaid
In Network Coverage Type(s): HMO
Payor Type:
In Network Coverage Type(s): HMO
Payor Type:
In Network Coverage Type(s): PPO
Payor Type: Commercial
In Network Coverage Type(s): EPO, HMO, PPO, POS
Payor Type: Medicaid/Managed Medicaid
In Network Coverage Type(s): HMO
Payor Type:
In Network Coverage Type(s): HMO, PPO
Payor Type: Commercial
In Network Coverage Type(s): PPO EPO
Payor Type: Commercial
In Network Coverage Type(s): HMO
Payor Type: Commercial
In Network Coverage Type(s): PPO
Payor Type: Commercial
In Network Coverage Type(s): EPO
Payor Type: Commercial
In Network Coverage Type(s): EPO
Payor Type:
In Network Coverage Type(s): PPO, HMO
Payor Type: Medicaid/Managed Medicaid
In Network Coverage Type(s): State Government
Payor Type: Commercial
In Network Coverage Type(s): PPO, POS, EPO
Payor Type:
In Network Coverage Type(s): Federal Government
Payor Type: Commercial
In Network Coverage Type(s): Supplemental
Payor Type: Commercial
In Network Coverage Type(s): PPO/OAP
Payor Type: Other
In Network Coverage Type(s): PPO, POS, EPO, HMO
Payor Type:
In Network Coverage Type(s): TBD
Payor Type: Commercial
In Network Coverage Type(s): HMO/EPO
Payor Type: Commercial
In Network Coverage Type(s): PPO, EPO
Payor Type: Commercial
In Network Coverage Type(s): PPO, POS, HMO
Payor Type: Medicaid/Managed Medicaid
In Network Coverage Type(s): State Government
Payor Type: Medicaid/Managed Medicaid
In Network Coverage Type(s): State Government
Payor Type: Commercial
In Network Coverage Type(s): PPO, HMO
Payor Type: Commercial
In Network Coverage Type(s): PPO, POS
Payor Type: Commercial
In Network Coverage Type(s): PPO, POS, HMO
Payor Type: Commercial
In Network Coverage Type(s): State Government
Contact and Location
- 212-639-6072 Office Phone
- Speaks English

Memorial Sloan Kettering has locations throughout New York City, Long Island, New Jersey, and Westchester. These locations offer many services, including screening, chemotherapy, and medical testing.
See all locationsAbout Me
Education
MBBS, University of London
Residencies
Medicine - University of London Teaching Hospitals
Fellowships
Clinical Oncology - Royal Marsden Hospital; Radiation Oncology - Harvard Medical School
Board Certifications
Radiation Oncology; Internal Medicine (UK)
I am a radiation oncologist who cares for people with breast cancer. I am Chair of the Department of Radiation Oncology and have been practicing medicine for 35 years. I see approximately 200 new breast cancer patients each year at Memorial Sloan Kettering in Manhattan.
Read more
When patients come to see me, they are worried about whether we can get rid of their cancer. Many patients read about their diagnosis on the internet, and the information they find can be very scary. I always make it a priority to answer all of my patients’ questions so that they feel reassured. I want them to know that they are getting the best care possible.
My research is focused on breast cancer. I have received funding from the National Institutes of Health since 1992 and am an expert in understanding how DNA repair genes like BRCA1 and BRCA2 work to fix DNA damage, as well as how a person’s genetics may influence his or her response to radiation therapy.
At MSK, we are leading the way in the use of advanced radiation techniques to ensure our patients have the best outcomes possible. For our early-stage breast cancer patients, we are using hypofractionated whole-breast irradiation. This means patients are receiving fewer total treatment sessions in a shorter time period, with a slightly higher dose given each treatment day. We also have a robust delivery system for partial breast irradiation. We now deliver treatment once per day, which helps our patients tolerate their treatment better.
I have experience treating people with recurrent or metastatic triple-negative breast cancer using radiation in combination with chemotherapy, targeted therapies, and immunotherapies.
For some people, breast cancer treatment can negatively affect the heart. At MSK, we have a program dedicated to assessing this problem. We are leaders in the field of deep inspiration breath-hold techniques, which can help lessen the cardiac side effects for our breast cancer patients. We are also using proton therapy to target tumors more precisely, which can reduce the risk of other treatment-related side effects.
I am a member of advisory boards for several cancer centers in the US and abroad, including the Netherlands Cancer Institute, Winship Cancer Institute of Emory University, University of Michigan Cancer Center, and the University of Florida Health Cancer Center.
In my free time, I enjoy theater, opera, ballet, country-specific versions of history, football, American football, and golf.
I always make it a priority to answer all of my patients’ questions so that they feel reassured. I want them to know that they are getting the best care possible.
-Dr. Powell
Awards and Honors
- Castle Connolly: America's Top Doctors (2023)
- Castle Connolly: New York Magazine Top Doctors (2016-2020)
- Top Doctors New York Metro Area
- Boston Top Doctors
- St. Louis Top Doctors
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.
See all Radiation Oncology doctors
See all External Beam Radiotherapy Service, Manhattan doctors
Clinical Trials
- Clinical Trials Co-Investigated by Dr. Powell
- A Phase I Study of XRD-0394 in People with Cancer Who Are Receiving Palliative Radiation Therapy
- A Phase II Study of Radiation Therapy with Pembrolizumab Immunotherapy and Olaparib in Women with Triple-Negative Breast Cancer
- A Phase II Study of Three-Day Partial Breast Radiation Therapy in Women with Breast Cancer
- A Study Assessing a Shortened Radiation Therapy Schedule in People Who Had a Mastectomy for Early Breast Cancer
Read more

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.
Search clinical trialsResearch and Publications
My research is focused on breast cancer. I have received funding from the National Institutes of Health since 1992 and am an expert in understanding how DNA repair genes like BRCA1 and BRCA2 work to fix DNA damage, as well as how a person’s genetics may influence his or her response to radiation therapy.
Visit PubMed for a full listing of Dr. Powell’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.
See all on PubMedPatient Reviews
At MSK, we’re committed to delivering the best care to every patient. We use feedback from our patients to continue to improve our care. We also post patient reviews online to help you make healthcare choices. Learn more about our patient experience reviews.
Disclosures
Doctors and faculty members 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.
MSK requires doctors and faculty members 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.
Simon N. Powell discloses the following relationships and financial interests:
-
PharmaPier US LLC
Provision of Services (uncompensated) -
Rain Therapeutics Inc.
Provision of Services
-
Varian Medical Systems
Provision of Services
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 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, 2021 through disclosure submission in spring 2022). 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 [email protected].