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Radiation Oncology
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Mount Sinai Doctors ?
    • Specialty
    • Radiation Oncology
    • Languages
    • English
    • Portuguese
    • Russian
    • Spanish
    • Hospital Affiliations
    • Mount Sinai Morningside and Mount Sinai West
    • New York Eye and Ear Infirmary of Mount Sinai
    • Mount Sinai Beth Israel
    • Mount Sinai Queens
    • The Mount Sinai Hospital
    • Mount Sinai Brooklyn

Stanislav (Stas) Lazarev, MD is a radiation oncologist in the Department of Radiation Oncology at Mount Sinai and New York Proton Center. Dr. Lazarev's clinical practice is focused on the personalized treatment of pediatric malignancies and tumors of the central nervous system, including primary brain, metastatic brain tumors, metastatic spine tumors, and leptomeningeal disease. His research interests include re-irradiation of brain tumors, proton craniospinal irradiation for leptomeningeal disease, and as well as the role of proton radiation therapy for pediatric tumors.  He is an active member of ASTRO, PTCOG, PROS/SIOP, and Cure4Kids Initiative (The St. Jude International Outreach Program). He is a co-investigator in a number of prospective studies examining safety and efficacy of proton radiotherapy. He sees his patients in New York Proton Center, Mount Sinai Hospital (Manhattan) and Mount Sinai Queens. He is actively involved in mentoring and teaching trainees, especially residents and medication students.

Dr. Lazarev graduated magna cum laude from University of California--Berkeley with a BA in Biochemistry and Molecular Biology, and received his medical degree from the University of Vermont College of Medicine where he also was inducted into the Alpha Omega Alpha National Honor Medical Society. He completed medicine internship at Highland Hospital in Oakland, California, and radiation oncology residency at the Icahn School of Medicine at Mount Sinai. He served as chief resident in the period 2018-2019. He has published numerous peer-reviewed papers on a broad range of oncological topics, and presented his work at national conferences. Dr. Lazarev was born and raised in southern Russia. He is fluent in English, Russian, Spanish, Portuguese, and proficient in French.


Radiation Oncology

Clinical Focus


MD, University of Vermont College of Medicine

Internship, Internal Medicine
Highland Hospital

Residency, Radiation Oncology
Icahn School of Medicine at Mount Sinai


English, Portuguese, Russian, Spanish