
Gregory Harrison Nalesnik, DO, FAAP
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.
Areas of Expertise
Conditions I Treat
- Pediatric bone tumors
- Pediatric brain tumors
- Pediatric leukemias
My Specialties
- Pediatric cancer care
- Adolescent and young adult (AYA) cancer care
- Lumbar puncture (spinal tap)
Get to Know Me
I am a general pediatric oncologist who cares for children and young adults with all types of cancer including:
- Leukemias
- Lymphomas
- Bone and soft tissue tumors
- Nerve tumors
- Brain tumors
I provide care on the MSK Kids inpatient unit at Memorial Hospital as well as outpatient care. My patients receive different types of treatments, including chemotherapy, immunotherapy, radiation therapy, and surgery, depending on the cancer diagnosis.
When I meet a new patient and their family, I put myself in their shoes. My priority is to get to know them and build a relationship and trust with them. Once I have earned their trust, I can address the disease.
Read more
In addition to patient care, I conduct research. As a fellow, I conducted laboratory research on high-risk leukemia, which has a higher chance of not responding to treatment or coming back compared to standard-risk leukemia. Here at MSK, I study Ewing sarcoma and other challenging cancers.
My goal is to explore new therapies to improve patient outcomes for some of the most aggressive pediatric cancers. This includes developing adaptive therapies for children with aggressive cancers, Ideally, we would give patients with aggressive cancers more intensive treatment than those with slower-growing cancers. Our aim is to treat these cancers strongly from the outset, rather than waiting until after they came back.
I chose pediatric oncology for several reasons. First, both my parents are cancer survivors. Their success stories of getting early, effective treatment is the reason they are still with us today. This inspired me to go to medical school and become a doctor. I specialized in pediatric oncology because I love working with children.
If you’re successful in treating a child who has cancer, you can potentially add many years to their life. I enjoy receiving emails and pictures from the families I’ve treated. It’s great to see them sharing the news of their children starting preschool, graduating high school, or seeing their families grow.
At MSK Kids, I am gratified to care for these amazing children and help them through the most difficult time of their lives. I don’t take that responsibility lightly, and I feel truly blessed.
A pediatric hematologist-oncologist is a doctor who treats cancers and blood diseases in children, adolescents and young adults.
- Assistant Attending Physician
Conditions I Treat
- Pediatric bone tumors
- Pediatric brain tumors
- Pediatric leukemias
- Pediatric lymphomas
- Pediatric sarcomas
- Pediatric spinal tumors
- Graft-versus-host-disease (GVHD)
- Histiocytosis
- Rare blood cancers and conditions
My Specialties
- Pediatric cancer care
- Adolescent and young adult (AYA) cancer care
- Lumbar puncture (spinal tap)
- Bone marrow aspiration
- Bone marrow biopsy
Education
- Doctor of Osteopathic Medicine (DO), University of Pikeville
Residencies
- Pediatrics, K. Hovnanian Children's Hospital
Fellowships
- Pediatric Hematology-Oncology, Penn State Children's Hospital
Board Certifications
- Pediatrics
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.
In Network Coverage Type
PPO
In Network Coverage Type
PPO, POS, EPO, HMO
In Network Coverage Type
HMO, PPO
In Network Coverage Type
HMO, EPO PPO, POS
In Network Coverage Type
PPO, POS, EPO, HMO
Offers a qualified health plan from the Health Insurance Marketplace. Call Emblem to learn more.
In Network Coverage Type
PPO, HMO
In Network Coverage Type
PPO
In Network Coverage Type
HMO, EPO
Offers a qualified health plan from the Health Insurance Marketplace. Call Fidelis to learn more.
In Network Coverage Type
EPO, HMO, PPO, POS
Offers a qualified health plan from the Health Insurance Marketplace. Call Healthfirst to learn more.
In Network Coverage Type
HMO
In Network Coverage Type
PPO
In Network Coverage Type
EPO
In Network Coverage Type
EPO
In Network Coverage Type
Federal Government
In Network Coverage Type
HMO
City Employee Health Plans (Gold and Gold Care)
In Network Coverage Type
PPO, POS, EPO, HMO
In Network Coverage Type
State Government
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.
Make an Appointment

Contact and Location
Dr. Nalesnik sees patients at one location.







Looking to see a doctor at a different location? See all MSK locations.
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.
Clinical Trials

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
Bogush, D., Schramm, J., Ding, Y., He, B., Singh, C., Sharma, A., Tukaramrao, D.B., Iyer, S., Desai, D., Nalesnik, G. and Hengst, J., 2023. Signaling pathways and regulation of gene expression in hematopoietic cells. Advances in Biological Regulation, 88, p.100942.
Melendez, A., Lee, J., Nalesnik, G., Barsoom, R., King, D., Tine, E., MvAleavy, M., DasMahapatra, B., Doll, R.J. and Theivakumar, T., 2012, August. 8-Quinolyl-N-arylcarbamates as re-activators of mutant p53 and potential antitumor agents. In ABSTRACTS OF PAPERS OF THE AMERICAN CHEMICAL SOCIETY (Vol. 244). 1155 16TH ST, NW, WASHINGTON, DC 20036 USA: AMER CHEMICAL SOC.
Visit PubMed for a full listing of Dr. Nalesnik’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 PubMed