Margaret K. Callahan, MD, PhD

About Me

I am a board-certified medical oncologist who specializes in the use of novel immunotherapies, which act by stimulating or strengthening the immune system’s inherent ability to fight cancer, to treat melanoma and other cancers. I work closely with a multidisciplinary team of medical oncologists, surgeons, radiation oncologists, and research nurses in the Immunotherapeutics Clinical Core (a specialized center for phase I clinical trials of new immunotherapy agents) and on the Melanoma and Sarcoma Service.

My research is focused on the development of new ways to use the immune system to treat cancer. As a laboratory member in the Ludwig Center for Cancer Immunotherapy at Memorial Sloan Kettering, I have been involved in developing innovative approaches to monitoring patients treated with immunotherapy. Our hope is to better understand how immunotherapy can be used to help patients with cancer and to expand this promising treatment modality into new areas.

  • Clinical Expertise: Melanoma; Immunotherapy
  • Languages Spoken: English
  • Education: MD, University of Connecticut
  • Residencies: Internal Medicine - University of California San Francisco
  • Fellowships: Medical Oncology/Hematology - Memorial Sloan Kettering Cancer Center
  • Board Certifications: Internal Medicine; Medical Oncology

My Research

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See Margaret K. Callahan’s laboratory
research at Memorial Sloan Kettering.


Visit PubMed for a full listing of Margaret K. Callahan’s journal articles

Pubmed is an online index of biomedical articles maintained by the U.S. National Library of Medicine and the National Institutes of Health.

Clinical Trials

Research is integral to our mission at Memorial Sloan Kettering, and clinical trials help us discover better forms of patient care and treatment. For you, this could mean access to a new therapy or therapy combination. Click to see a list of the trials I’m currently leading.


Most major health insurers offer plans that include MSK as one of their in-network providers. If MSK is in-network, it means all our doctors are too. Medicaid and New York State Medicare also provide benefits for care at MSK.

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