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.
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.
MD, PhD, University of Connecticut School of Medicine
Residencies
Internal Medicine, University of California, San Francisco, Medical Center
Fellowships
Medical Oncology, Memorial Sloan Kettering Cancer Center
Board Certifications
Internal Medicine; Medical Oncology
I am a board-certified medical oncologist specializing in the use of novel immunotherapies to treat melanoma and other cancers. Immunotherapies act by stimulating or strengthening the immune system’s inherent ability to fight cancer. In recent decades, this treatment option — particularly a type of immunotherapy called checkpoint inhibitors — has significantly improved outcomes for many patients with melanoma, including those with advanced disease.
As the Research Director for Immunotherapy within the Early Drug Development Service at Memorial Sloan Kettering Cancer Center (MSK), my research focuses on developing new ways to use the immune system to treat cancer and better tools to use existing immunotherapy options. During my time at MSK, I have led efforts to identify biomarkers that can predict which patients will respond to checkpoint inhibitors. Additionally, I have led many phase one clinical trials testing novel immunotherapies in development for patients with melanoma and other malignancies.
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Taking a collaborative approach is important to me not only in research, but also in patient care. Treating melanoma is a multidisciplinary effort. I work closely with a team of medical oncologists, surgeons, radiation oncologists, and research nurses on our Melanoma and Early Drug Development Services. My patients are at the heart of this team; we all work together to craft a treatment plan that is right for each person who comes to us for care. I want patients to feel involved and part of the decision-making process. The strong relationships that we forge along the way are some of the most fulfilling aspects of my work as a medical oncologist. I value the opportunity to serve as a resource to help patients understand their diagnosis, treatment options, and what to expect at each step in the process.
When I am not conducting research or seeing patients, I can be found chasing two young children and a labradoodle puppy, who keep me busy in my free time.
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.
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.
Visit PubMed for a full listing of Dr. Callahan’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.
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.
Margaret K. Callahan discloses the following relationships and financial interests:
AstraZeneca Provision of Services
Axios Provision of Services
Bristol-Myers Squibb Provision of Services (uncompensated)
Celldex Therapeutics Provision of Services
Clinical Care Options Provision of Services
Incyte Provision of Services
Merck & Co Inc. Provision of Services
Moderna, Inc. 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].
