Mark B. Geyer, MD
Adolescent and Young Adult Program Leader, Leukemia Service
Adult Acute and Chronic Leukemias; Acute Lymphoblastic Leukemia (ALL); Chronic Lymphocytic Leukemia (CLL); Chronic Myeloid Leukemia (CML); Hairy Cell Leukemia; Lymphoproliferative Disorders; Cellular Immunotherapy
New Patient Appointments
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Dr. Geyer accepts the following list of insurance providers. Select your insurance provider to see more details.
Memorial Sloan Kettering is an in-network provider with Aetna HMO, POS, and PPO plans. Aetna does not include us in any of the plans you can purchase through the insurance exchanges or through Medicare. Please ask your insurance if you need a one-time referral. MSK has an agreement with the Aetna Transplant Program for all Aetna's commercial products.
Memorial Sloan Kettering is a designated Blue Distinction Center for bone marrow transplant and CAR-T.
We understand that there may be many complexities involved with insurance coverage purchased through the health exchange network of the Affordable Care Act. We’re here to help. If you have questions about how your care will be covered by an insurance provider, or need help navigating a change in coverage, please call us at 646-227-3378; if you are not a resident of New York, you can call us at 866-248-1274. Our team is here to listen to your concerns and assist you in any way we can. We want our care to be as accessible and affordable for as many people as possible.
Memorial Sloan Kettering is an in-network provider with CIGNA's HMO, POS, and PPO plans. CIGNA does not include us in any of the plans you can buy through the insurance exchanges.
- If you are a New York State resident: Please ask your insurance if you need a one-time referral.
- If you live outside of New York State: Please ask your insurance if you have in-network access to Memorial Sloan Kettering.
Memorial Sloan Kettering is an in-network provider with EmblemHealth’s PPO, EPO, POS, HMO plans. EmblemHealth includes GHI, HIP, Vytra, and ConnecticCare (in NYS Only). You must bring a referral from your Emblem primary care doctor to your first appointment. In-network participation exceptions include:
- Emblem’s HIP Commercial Millennium, Select Care and Enhanced Care Prime networks is not in-network with Memorial Sloan Kettering.
- Please call Emblem to confirm if your specific plan is in-network.
For information regarding Memorial Sloan Kettering’s participation with Emblem’s Medicare Advantage Plans, please refer to the Medicare & Medicaid page
Memorial Sloan Kettering is an in-network provider with Empire Blue Cross Blue Shield (Wellpoint) of New York Indemnity, HMO, EPO, PPO, POS and Medicare Advantage plans, with the following exceptions:
- Empire Blue Cross Blue Shield does not include us in any of the plans you can buy through the insurance exchanges.
- Please call Empire BCBS to confirm if your specific plan is in-network with Memorial Sloan Kettering.
Memorial Sloan Kettering is an in-network provider with HealthFirst’s commercial products; these commercial products are not purchased on the insurance exchanges.
Memorial Sloan Kettering is an in-network provider with HealthSmart’s Accel, HSPC, and HPO networks.
For our NJ locations, Memorial Sloan Kettering is an in-network provider with most Horizon Blue Cross Blue Shield of New Jersey plans for individuals, families, and small businesses. Horizon members with Blue Card Access (there would be a suitcase logo on the front of the card) may have access to our NY locations. Please call Horizon to confirm if your plan is in-network in NY.
Memorial Sloan Kettering is a designated Center of Excellence by Humana.
Memorial Sloan Kettering is a designated Center of Excellence by Interlink Health Services.
Memorial Sloan Kettering is a designated Center of Excellence by Lifetrac.
Memorial Sloan Kettering is an in-network provider for all MagnaCare health plans except those products you can buy through the insurance exchanges.
For information about Medicare and Medicaid, please visit this page
Memorial Sloan Kettering is an in-network provider with some Multiplan/Beech Street/PHCS plans. Contact your insurance carrier to find out if your plan provides in-network access to Memorial Sloan Kettering.
Memorial Sloan Kettering is a designated Center of Excellence by Multiplan.
If you are covered by more than one insurance plan, you will want to determine your benefits from both plans. First, you need to determine which one is your primary insurance provider by contacting your employee benefits office or your insurance carriers. After you find out which is your primary insurance provider, you should then contact your insurance carrier to determine if you have access to Memorial Sloan Kettering.
Memorial Sloan Kettering is an in-network provider with some MVP plans. Contact your insurance carrier to find out if your plan provides in-network access to Memorial Sloan Kettering.
Memorial Sloan Kettering is an in-network provider for New York State employees who have enrolled in UnitedHealthcare's Cancer Resource Services. If you have the Empire Plan, you should call Cancer Resources Services at 866-936-6002 to verify and enroll in this coverage.
Memorial Sloan Kettering is in-network with Oscar’s Circle Plus Network, a part of its Small Group Broad line that is offered only to select small business groups. Oscar does not include Memorial Sloan Kettering as an in-network provider for any of its individual plans. Please confirm eligibility with your insurance carrier.
Most Blue Cross Blue Shield plans include Memorial Sloan Kettering as an in-network provider. Contact your insurance company to confirm if Memorial Sloan Kettering is in-network.
We have agreements with several insurance companies that may provide additional coverage for cancer patients. These benefit programs include:
- AXA Assistance USA
- Beech Street
- Integrated Health Plans
- National Health Administrators
- National Preferred Provider Network
- UnitedHealthcare's Cancer Resource Services
- United Resource Network
- Veterans Choice Program
Memorial Sloan Kettering is an in-network provider with Oxford’s Freedom and Liberty plans as well as the Metro Plan (which is only offered to small business groups and no longer offered as individual plans). Please confirm with your insurance if you need a one-time referral. Note: Oxford’s Medicare Managed Care plan — Secure Horizon — does not include Memorial Sloan Kettering as an in-network provider. Oxford does not include us in any of the plans you can buy through the insurance exchanges.
Memorial Sloan Kettering is an in-network provider with the World Trade Center Health Program.
Memorial Sloan Kettering is an in-network provider with QualCare's PPO and HMO/POS network.
Memorial Sloan Kettering is a designated Center of Excellence by Specialty Care Management.
Hospital and physician services may be covered by TRICARE. Please call your TRICARE plan to confirm coverage at Memorial Sloan Kettering.
Memorial Sloan Kettering is an in-network provider with UnitedHealthCare's HMO, POS, and PPO plans. Please confirm with your insurance if a one-time referral is needed.
UnitedHealthCare's Medicare Managed Care plan does not include Memorial Sloan Kettering as an in-network provider.
United does not include us in any of the plans you can buy through the insurance exchanges.
Memorial Sloan Kettering is a designated Center of Excellence by UnitedHealthcare.
Contact and Location
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, Columbia University College of Physicians and Surgeons
Internal Medicine – Massachusetts General Hospital
Hematology/Medical Oncology – Memorial Sloan Kettering Cancer Center
Internal Medicine; Hematology; Medical Oncology
I am a hematologist and medical oncologist who specializes in caring for people with leukemia. I am a member of the Leukemia Service and Center for Cell Engineering at Memorial Sloan Kettering. I am committed to providing personalized, compassionate care for our patients and their families.
I often meet patients and their families and caregivers during a very challenging and emotionally charged period in their lives. I value the strong partnerships I form with our patients and their caregivers through both illness and wellness. I want us to make important decisions about care together.
Caring for and adolescent and young adult (AYA) patients with leukemia is particularly important to me. At the time of their diagnosis, many AYAs with leukemia are continuing education or training, starting their careers, and building relationships and families. In my role as AYA Program Leader for the Leukemia Service, I work with other providers in the Lisa and Scott Stuart Center for Adolescent and Young Adult Cancers to meet the unique medical, social, and emotional needs of our AYA patients and their families. These efforts include ensuring our AYA patients have access to well-designed clinical trials run by both the Pediatric and Adult Leukemia Services.
As a researcher, I want to improve the way we treat blood cancers. My research focuses on learning about and developing safe and effective therapies for acute lymphoblastic leukemia and other lymphocytic cancers. I have a strong interest, for example, in using the power of the immune system to fight blood cancers more effectively. This treatment approach is called immunotherapy. I am working to develop and deliver chimeric antigen receptor T cell therapies for people with leukemia or lymphoma. This field holds great promise, though it has a different set of challenges compared with traditional chemotherapy. Because of the skill and experience of the nurses and doctors at MSK, we can deliver the newest treatments in the safest possible manner.
When I meet with patients, my goal is for them to leave the appointment feeling informed and empowered. I want them to know that they are in good hands. I listen carefully to their perspective and address their concerns. I also explain the range of options available to us, outline the advantages and disadvantages of each, and offer my recommendation. I often remind my patients and their families that we never stop caring for them. Our entire team of experts will be there to support and guide them through all the stages of their journey.
Awards and Honors
- Memorial Sloan Kettering Hematology Attending Teaching Award (2020-2021)
- American Society of Hematology Scholar Award (2018-2020)
- Lymphoma Research Foundation Postdoctoral Fellowship Grant (2017-2019)
- Abstract Achievement Award, American Society of Hematology (2016)
- Conquer Cancer Foundation Merit Award, American Society of Clinical Oncology (2016)
- Clinical Trials Investigated by Dr. Geyer
- A Phase II Study of Blinatumomab and Tyrosine Kinase Inhibitor Therapy in People with Philadelphia Chromosome-Positive Acute Lymphoblastic Leukemia
- A Pilot Study of 131-I Apamistamab and CAR T-Cell Therapy in People with Recurrent or Persistent Leukemia or Lymphoma
- Clinical Trials Co-Investigated by Dr. Geyer
- A Phase IB/II Study of AUTO1 CAR T-Cell Therapy in People with Recurrent or Persistent B-Cell Acute Lymphoblastic Leukemia: The FELIX Trial
- A Phase III Study of Panzyga to Prevent Infection in People with Chronic Lymphocytic Leukemia
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.
Research and Publications
Geyer MB, Rivière I, Sénéchal B, Wang X, Wang Y, Purdon TJ, Hsu M, Devlin SM, Halton E, van Leeuwen DG, Sadelain M, Palomba ML, Park JH, Brentjens RJ. 2019. Safety and tolerability of conditioning chemotherapy followed by CD19-targeted CAR T-cells for relapsed/refractory CLL. JCI Insight. 4(9): e122627.
King AC, Pappacena JJ, Tallman MS, Park JH, Geyer MB. 2019. Blinatumomab Administered Concurrently with Oral Tyrosine Kinase Inhibitor Therapy is a Well-Tolerated Consolidation Strategy and Eradicates Measurable Residual Disease in Adults with Philadelphia Chromosome Positive Acute Lymphoblastic Leukemia. Leukemia Research. 79: 27-33.
Visit PubMed for a full listing of Dr. Geyer’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.
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.
Mark B. Geyer discloses the following relationships and financial interests:
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, 2020 through disclosure submission in spring 2021). This data reflects interests that may or may not still exist. This data is updated annually.