Our residents come from diverse educational and personal backgrounds, but all share a passion for radiation oncology clinical practice and research. We are also fortunate to have two fellows as part of our department, specializing in brachytherapy and protons.
We work and learn together — in a single residents’ room — and consider the camaraderie of the residents and fellows one of the major strengths of our residency program.
First-Year Residents (July 2020 – June 2024)
David Billing, MD, PhDI grew up in Gales Ferry, Connecticut and attended Harvard University where I received my bachelor’s degree in molecular and cellular biology. I then entered the MD/PhD program at Columbia University College of Physicians and Surgeons. For my doctoral thesis in Richard Baer’s lab, I studied the role of the BRCA1/BARD1 heterodimer in DNA damage response and breast cancer pathogenesis. I completed a transitional year internship at MSK prior to joining the radiation oncology residency program.
Bill Diplas, MD, PhDI grew up in Blacksburg, Virginia. I attended Johns Hopkins University for my undergraduate degree in biomedical engineering. During and after college, I did genetics and biomedical engineering research at Johns Hopkins and then at the Swiss Federal Institute of Technology Lausanne (EPFL) through the Whitaker Fellowship. I then joined the MD/PhD program at Duke University School of Medicine, where I did my doctoral research on cancer genomics and neuro-oncology, funded by the NCI F30, in the laboratory of Hai Yan. My work focused on identifying novel genomic alterations in glioblastoma, understanding their roles in telomere maintenance, and developing sensitive mutation-detection tools with applications in liquid biopsy. I completed a transitional year internship at MSK prior to joining the Radiation Oncology Residency Program.
Jennifer Ma, MDI grew up on Long Island, New York and completed my undergraduate studies at Fordham University, where I majored in biology and completed my honors thesis on the genetic regulation of cell differentiation. I conducted clinical research on hepatobiliary cancers at MSK before attending medical school at the Albert Einstein College of Medicine in the Bronx. During medical school, I completed a two-year graduate research fellowship in the laboratory of Simon Powell at MSK, where I developed an interest in genetic drivers of radiotherapy response. My work focused on the role of DNA repair genes as biomarkers of radiosensitivity for the development of targeted therapies. I completed my transitional year internship at Amita Saint Francis Hospital in Chicago and am excited to join the Radiation Oncology program at MSK.
Patricia Santos, MDI was born in Manila, Philippines but grew up in Brooklyn, New York. I attended Brooklyn Technical High School before pursing undergraduate studies at Brown University, where I studied neuroscience and history. I obtained my master’s in biomedical sciences at the Icahn School of Medicine at Mount Sinai, studying gene-environment interactions at the gut-brain interface. I later discovered my love for multidisciplinary cancer care as a medical student at the Perelman School of Medicine at the University of Pennsylvania. Inspired by time on the wards, I began research at MSK, using advanced imaging to monitor tumor response to radiotherapy. Meanwhile at Penn, under the mentorship of Neha Vapiwala, I studied the comparative effectiveness of proton versus photon therapy in mitigating toxicity in patients with prostate cancer. Additionally, I have been involved in a variety of research endeavors that encompass my broad interests in health services, medical education, ethics, and end-of-life care. I completed my transitional year internship at MSK and am excited to continue my training in the Radiation Oncology Residency Program.
Reith Sarkar, MDI was born and raised in Orange County, California and attended college at Washington University in St. Louis, where I majored in biomedical engineering. I then attended medical school at the University of California, San Diego, where I was first introduced to the field of radiation oncology. During medical school, I developed an interest in cost-effectiveness, health services, and big data research. Between my third and fourth years of medical school I obtained a master’s degree in clinical research, and under the mentorship of James Murphy and Brent Rose, completed a thesis on the role of finasteride in delaying the diagnosis of prostate cancer. Before joining the Radiation Oncology Residency Program at MSK, I completed a transitional year internship at Scripps Mercy Hospital in San Diego.
Deborah Smith, MDBorn in Manhattan and raised in Connecticut, I attended Brown University where I studied classics and molecular biology. Afterward, I moved to Washington, DC, where I worked as a research fellow at the National Cancer Institute investigating regulatory links between chromatin, telomere protection, DNA replication and genome integrity. I returned to New York for medical school at Columbia University, where I also completed a master’s of science and Dean’s Research Fellowship conducting clinical and translational research on primary and metastatic brain tumors. Following a transitional year internship at MSK, I joined the Radiation Oncology Residency Program.
Second-Year Residents (July 2019 – June 2023)
Morgan FreretBorn and raised in Northern California, I majored in biology at Stanford University. My interest in medicine developed after I joined a Stanford biochemistry laboratory that was investigating a signaling pathway important in the pathogenesis of a type of pediatric brain tumor. I completed my MD/PhD training at Harvard Medical School. My PhD research characterized molecular and functional subtypes of brain serotonergic neurons in mice. I joined the Radiation Oncology Residency Program after my transitional year internship at MSK.
Harper HubbelingI grew up in Austin, Texas, and got my undergraduate degree in biology from Haverford College in Pennsylvania, where I studied patrolling monocyte development. After college I worked at the University of Pennsylvania in an immunology lab investigating how immune cell subsets affect the intestinal microbiome. I then attended Harvard Medical School, where I did clinical research in thoracic oncology with Alice Shaw’s group. I completed a transitional year internship at MSK before joining the Radiation Oncology Residency Program.
Emily Schapira LebowI grew up in Milwaukee, Wisconsin, and received my undergraduate degree from the University of Pennsylvania. I attended Harvard Medical School, where I spent a year doing clinical research under the mentorship of Helen Shih at Massachusetts General Hospital. I studied the integration of radiation therapy and immunotherapy, with a focus on treating people with cancer that has spread to the brain. I completed a transitional year internship at MSK before joining the Radiation Oncology Residency Program.
Zachary MooreI grew up in Texas and attended the University of Texas at Austin, where I studied biomedical engineering and designed nanoparticles for targeted drug delivery. After completing my undergraduate degree, I went to the University of Texas Southwestern Medical Center in Dallas to complete my MD and PhD. For my doctoral research I studied tumor-targeted DNA-damaging agents and combination treatment strategies for pancreatic cancer and lung cancer. Before joining the Radiation Oncology Residency Program at MSK, I completed a transitional year internship at Scripps Mercy Hospital in San Diego.
Victor NgI was born and raised in San Jose, California, and obtained my bachelor’s degree from the University of California, Berkeley, where I majored in bioengineering. I then developed a significant interest in the pathogenesis and maintenance of cancer while studying leukemia stem cells at the University of California, San Francisco. My studies subsequently brought me to the University of Michigan, where I not only received a master’s degree in biomedical engineering but also learned lifelong lessons on the compassionate care of people with cancer as a hospice volunteer. I traveled to New York for my medical studies at the New York University School of Medicine and then did a transitional year internship at MSK. I am grateful to be continuing my training in the Radiation Oncology Residency Program at MSK.
Kathryn TringaleI grew up in the San Francisco Bay Area and attended Brown University, where I received my degree in biomedical engineering. Before attending medical school at the University of California, San Diego, I continued my undergraduate thesis work in brain computer interface clinical trials with the BrainGate group at Massachusetts General Hospital in Boston. Throughout medical school, I was involved in a variety of research endeavors, including cost-effectiveness, clinical trials, and medical ethics. The thesis for my master’s degree in clinical research investigated the use of advanced diffusion imaging techniques as biomarkers for neurocognitive performance in people undergoing brain radiotherapy. Before coming to MSK, I completed my preliminary year internship in internal medicine at Kaiser Permanente in Los Angeles.
Third-Year Residents (July 2018 – June 2022)
Ishita Chen, MD, PhDI grew up in India and got my undergraduate degree in biomedical engineering from the University of Toledo in Ohio. In college I did medical imaging research at the Mayo Clinic. I obtained my PhD in biomedical engineering at Vanderbilt University in Nashville. While there I worked on adapting an atlas-based biomechanical model for a neurosurgical image guidance system. I attended medical school at Washington University in St. Louis, where I continued to work on image guidance in radiation therapy. I completed a preliminary medicine internship at St. Luke’s Hospital in Chesterfield, Missouri, prior to starting the Radiation Oncology Residency Program at MSK.
Xiaojing Huang, MD, PhDI was born in Guangzhou, China, and grew up in Utah and New Jersey, where I did my undergraduate degree in chemistry at Princeton University. After college I worked at Massachusetts General Hospital in a cardiac stem cell lab. I then moved to a medical scientist training program at Washington University in St. Louis. I did my graduate work in mass spectrometry–based metabolomics and macrophage metabolism. During my clinical years I extended my metabolomics studies to investigate how cervical cancer cells adapt their metabolic programs when undergoing chemoradiation. I completed my intern year in the internal medicine program at Barnes-Jewish Hospital in St. Louis.
Dillon Li, MD, MPHI grew up in Inner Mongolia, China. I attended Peking University in Beijing, where I received my undergraduate degree in biomedical sciences. I then joined Ramanujan Hegde’s lab at the National Institutes of Health to study membrane protein biology as a Student Intramural Research and Training Award recipient. I received an MPH degree from the University of Cincinnati prior to attending medical school at the University of Kentucky College of Medicine. In medical school I joined David Yu’s lab at Emory University in Atlanta and studied DNA damage repair. I was also involved in clinical research evaluating a stereotactic body radiation therapy boost for locally advanced lung cancer. I completed a transitional year internship at Santa Clara Valley Medical Center in California prior to joining the Radiation Oncology Residency Program at MSK.
Achraf Shamseddine, MD, PhDI was born in Lebanon and did my undergraduate studies at the American University of Beirut. I completed my MD/PhD at SUNY Stony Brook. My work focused on the role of sphingolipids in the cellular DNA damage response. It also involved devising strategies to chemosensitize and radiosensitize breast cancer cells through the manipulation of sphingolipid enzymes. I completed a transitional year internship at MSK before joining the Radiation Oncology Residency Program.
Neil Ari Wijetunga, MD, PhDI was born in North Dakota, but I grew up mostly outside of Philadelphia. I attended Boston University, where I majored in statistics and became interested in statistical genetics and public health. I then obtained a master’s degree in biostatistics at Columbia University. Afterward I joined the MD/PhD program at Albert Einstein College of Medicine in the Bronx, New York, where I studied the genomic and epigenetic effects of environmental exposures, including oncogenic viral infection and radiation exposure. Before coming to MSK I completed a medical internship at NYU Winthrop Hospital.
Fourth-Year Residents (July 2017 – June 2021)
Xin Cai, MD, PhD
I was born in China and grew up in Vancouver, Canada. I completed my undergraduate studies in chemistry and physics at Harvard University, where I also received a master’s degree in chemistry. I then joined the MD/PhD program at UT Southwestern Medical Center, where I studied the mechanism of innate immune and inflammatory signaling as a Howard Hughes Medical Institute fellow under the mentorship of Zhijian Chen. I completed a transitional year internship at MSK prior to joining the Radiation Oncology Residency Program.
Kelly Fitzgerald, MD, PhD
I grew up in Massachusetts and attended Boston College, where I received an undergraduate degree in biochemistry. I then entered the MD/PhD program at Yale School of Medicine. For my doctoral thesis, I designed and tested novel synthetic compounds that targeted prostate cancer for immune destruction. I completed a preliminary medicine internship at Yale New Haven Hospital before joining the Radiation Oncology Residency Program at Memorial Sloan Kettering.
Justin Haseltine, MD
I was born and raised in southwest Missouri. I majored in biomedical engineering at Duke. In college, my interest in research was sparked when I joined a lab focused on seeding human endothelial progenitor cells onto metal vascular implants with the goal of reducing blood clots. While earning my medical degree at Weill Cornell, I spent a year studying DNA damage repair in the lab of Simon Powell here at MSK. I was also fortunate to have the opportunity to spend a month of my medical training with radiation oncologists in India, which afforded me a unique perspective on the global delivery of care. I completed a medical internship at Brown University before joining MSK’s Radiation Oncology Residency Program.
Christopher Johnson, MD, PhD
I grew up in Chesapeake, Virginia, but spent much of my time across the state line in Currituck, North Carolina. After earning a chemistry degree from the University of North Carolina at Chapel Hill, I entered the Medical Scientist Training Program at the Medical University of South Carolina. As an MD/PhD student in David Cole’s lab, I studied the role of cytokines in adoptive T cell therapy. Upon graduation, I completed a transitional year internship at MedStar Harbor Hospital in Baltimore before joining the Radiation Oncology Residency Program at Memorial Sloan Kettering.
Leslie Modlin, MD
I grew up on the North Shore of Chicago and attended Duke University, where I designed a major to explore the biopsychosocial determinants of health and conducted neuro-oncology research. Before medical school at Stanford, I worked on clinical trials evaluating hypofractionated stereotactic radiosurgery for brain tumors under the mentorship of Scott Soltys. As a medical student, I continued my clinical and translational research on circulating tumor DNA as a Radiological Society of North America grant recipient in the lab of Max Diehn. I also led medical student wellness initiatives. I completed my internship at Cambridge Health Alliance of Harvard Medical School before joining the Radiation Oncology Residency Program at Memorial Sloan Kettering.
Mira Patel, MD
I was born and raised in Rochester, New York, and attended Cornell University, where I received degrees in political science and biological sciences. Subsequently, I completed my medical training at Johns Hopkins University School of Medicine, where I studied tumor immunology in a preclinical model of glioblastoma as a Howard Hughes Medical Institute research fellow. Prior to joining Memorial Sloan Kettering’s Radiation Oncology Residency Program, I completed a categorical internship in otolaryngology-head and neck surgery at Washington University/Barnes-Jewish Hospital in St. Louis.
Brachytherapy Fellow (July 2020-June 2021)
Assaf Moore, MDI grew up in Tel Aviv, Israel, and went to medical school at Tel Aviv University. I completed a general internship and residency in radiation oncology at Rabin Medical Center in central Israel. During my training I have enjoyed taking part in, and leading, multiple research projects. I was very excited to have the opportunity to join MSK as the brachytherapy fellow. This important modality has proved to be a key component in the care of prostate and gynecologic malignancies. It is my goal to become an expert in modern techniques, and to incorporate these skills in my future practice.