Christopher Duke, MD is a second-generation physician and native Washingtonian. His parents practiced medicine in Washington for four decades. Chris has practiced internal medicine here for 30 years. He attended George Washington University for his undergraduate and medical degrees. He completed Internal Medicine training at Penn State University. Chris practices evidence-based medicine while emphasizing empathy for his patients and their families. He personally knows and refers patients to the many outstanding specialists in Washington. He is excited to team with his patients to optimize their health and enjoyment of life. He has taught medical students at George Washington as an associate professor of medicine. He has been recognized by Washingtonian Magazine as a “Top Doctor” including in 2022. Outside of work, he enjoys traveling with wife Lilian and children Jacqueline and James. He loves attending Notre Dame football games and spoiling his pugs- Mini and Rockne! LinkedIn https://www.linkedin.com/in/christopher-duke-md-1126314. Dr. Duke is rated as an Advanced provider by MediFind in the treatment of Vitamin B12 Deficiency. His top areas of expertise are Rabson-Mendenhall Syndrome, Vitamin B12 Deficiency, Subacute Combined Degeneration, and Cellulitis.

Dr. Jose A. Quiros is an internist affiliated with Sibley Memorial Hospital and Suburban Hospital. He has a private practice in Bethesda, Md. Dr. Quiros earned his medical degree from the Universidad Nacional Mayor de San Marcos. He completed an internship and residency in internal medicine at Georgetown University Hospital. Dr. Quiros has been named a Top Doctor by Washingtonian magazine. Dr. Quiros is rated as an Advanced provider by MediFind in the treatment of Vitamin B12 Deficiency. His top areas of expertise are Glossitis, Pernicious Anemia, High Cholesterol, and Vitamin B12 Deficiency.

Dr. Edward T. Cullen is an internist affiliated with Sibley Memorial Hospital. He practices out of Cullen, Umosella, Cullen & Cullen in Bethesda, Md. and Oxon Hill, Md. Dr. Cullen earned his medical degree from Georgetown University School of Medicine. He completed an internship in internal medicine at St. Vincent Hospital, followed by a residency in internal medicine at Geisinger Medical Center. Dr. Cullen has been named a Super Doctor by the Washington Post and a Top MD by Consumers’ Checkbook Magazine, as well as a Top Family/General Practitioner by Washingtonian Magazine. Recent News Articles and Media Coverage The Brothers Cullen. Bethesda Magazine (January/February 2008). Dr. Cullen is rated as an Advanced provider by MediFind in the treatment of Vitamin B12 Deficiency. His top areas of expertise are Squamous Cell Lung Carcinoma, EGFR Positive Lung Cancer, Non-Small Cell Lung Cancer (NSCLC), and Small Cell Lung Cancer (SCLC).

Dr. Ralph V. Boccia is a hematologist affiliated with Sibley Memorial Hospital, Suburban Hospital, Shady Grove Adventist Hospital, Holy Cross Hospital and MedStar Georgetown University Hospital, where he is a clinical associate professor of medicine for the University, as well as the medical director of the International Oncology Network (ION) Clinical Research Program and the chairman of ION’s Medical Advisory Panel. He practices out of the Center for Cancer and Blood Disorders, of which he is the founder and medical director, located in Bethesda, Maryland and Germantown, Maryland. Dr. Boccia earned his medical degree from the Autonomous University of Guadalajara School of Medicine. He completed a residency in internal medicine at Kern Medical Center, followed by a fellowship in hematology, oncology and bone marrow transplant at the combined UCLA-Veterans Administration Program and The National Cancer Institute at the National Institutes of Health. Dr. Boccia is a member of the American College of Physicians, the American Society of Clinical Oncology, the American Society of Hematology and the American Society for Blood and Marrow Transplantation. Dr. Boccia has been listed as a Top Doctor by Washingtonian Magazine and Consumers’ Checkbook Magazine since 1992. He has also been recognized as a Super Doctor by The Washington Post Magazine and a Regional Top Doctor for Washington, D.C., Baltimore and Washington-Baltimore by Castle Connolly. Dr. Boccia has contributed to various articles with his research, published in journals such as Annals of Internal Medicine, Journal of Clinical Oncology and The Lancet. Recent News Articles and Media Coverage Bladder cancer trends in Montgomery and Prince George's counties: Welcome news - and 3 facts you need to know. NJ.com (08/16/2016) RCCA Expands to Maryland to Become One of the Nation's First Multi-State Oncology/Hematology Physician-Owned and -Operated Networks. OncLive (10/06/2015). Dr. Boccia is rated as an Advanced provider by MediFind in the treatment of Vitamin B12 Deficiency. His top areas of expertise are Anemia, Multiple Myeloma, Thrombocytopenia, Adult Immune Thrombocytopenia, and Splenectomy.

Victor Priego is a Hematologist Oncology specialist and an Oncologist in Bethesda, Maryland. Dr. Priego is rated as an Advanced provider by MediFind in the treatment of Vitamin B12 Deficiency. His top areas of expertise are Myelodysplastic Syndrome (MDS), Anemia, Hemangioma Thrombocytopenia Syndrome, Thrombocytopenia, and Splenectomy.

Mark Goldstein is a Hematologist Oncology provider in Bethesda, Maryland. Dr. Goldstein is rated as an Experienced provider by MediFind in the treatment of Vitamin B12 Deficiency. His top areas of expertise are Childhood Iron Deficiency Anemia, Anal Cancer, Myelodysplastic Syndrome (MDS), and Pleuropulmonary Blastoma.

"Dr. Rachit Kumar is a radiation oncologist specializing in genitourinary and gastrointestinal cancers. He is dedicated to patient-centered care, finding the most effective outcome for each patient and using the latest advances to minimize treatment time and side-effects. Dr. Kumar is frequently published in peer-reviewed journals on new methods of radiation therapy and the benefits to patient outcomes. He is a member of the Johns Hopkins Kimmel Cancer Center and treats patients at both Sibley Memorial Hospital and Suburban Hospital. Selected Publications Kumar R, Tchelebi LT, Anker CJ, Sharma N, Bianchi NA, Dragovic J, Goodman KA, Herman JM, Jiang Y, Jones WE, Kenney TJ, Lee P, Kundranda MK, Russo S, Small W, Suh WW, Yee N, and Jabbour SK. “American Radium Society (ARS) Appropriateness Use Criteria (AUC) for Loco-Regional Gastric Adenocarcinoma: Systemic Review and Guidelines.” American Journal of Clinical Oncology. 2022 Sep 1;45(9):391-402. Rooney MK, Traube B, Khan MK, Kumar R, and Walker GV. “Factors associated with image guided radiation therapy image rejection in a multi-site institution.” JCO Oncology Practice. Tang C, Hoffman KE, Allen PK, Gabel M, Schreiber D, Choi S, Chapin BF, Nguyen QN, Davis JW, Frank SJ, Navai N, McGuire SE, Anscher M, Pisters L, Pettaway CA, Kumar R, Linson P, Tripuraneni P, Tomaszewski JJ, Patel AB, Augspurger M, and Kuban DA. “Contemporary Prostate Cancer Treatment Choices in Multidisciplinary Clinics Referenced to National Trends.” Cancer. Tang C, Lei X, Smith GL, Pan HY, Hoffman K, Kumar R, Chapin BF, Shih YC, Frank SJ, and Smith BD. ""Influence of Geography on Prostate Cancer Treatment Coice: An Analysis of the National Medicare Database."" International Journal of Radiation Oncology Biology Physics. Tang C, Sherry AD, Haymaker C, Bathala T, Liu S, Fellman B, Aparicio A, Zurita-Saavedra A, Chun S, Reddy J, Choi S, Ghia A, McGuire S, Efstathiou E, Wang J, Wang J, Tu SM, Pilie P, Kovitz C, Kumar R, Roberts T, Borghero Y, Shi Z, Chapin B, Gomez D, Wistuba I, Corn and PG. “Addition of local consolidative therapy to intermittent hormone therapy for oligometastatic prostate cancer (EXTEND): a multicenter randomized phase II basket trial.” JAMA Oncology.". Dr. Kumar is rated as an Experienced provider by MediFind in the treatment of Vitamin B12 Deficiency. His top areas of expertise are Pancreatic Cancer, Familial Pancreatic Cancer, Pancreatoblastoma, and Prostate Cancer.

Dr. Carlos Picone served as Vice-Chair, Department of Internal Medicine at Sibley Memorial Hospital in Washington, D.C. and Chairman of the Pulmonary Medicine Division. Dr. Picone received his medical degree from the National University of Cordoba, Argentina in 1989, graduating summa cum laude. He completed a residency in Internal Medicine at the Medical College of Virginia, and Fellowships in Critical Care Medicine at the National Institutes of Health and in Pulmonary Medicine at the Medical College of Virginia. Dr. Picone has authored articles on pulmonary arterial hypertension and treatment, bioethics, end-of-life decision-making and parenchymal lung diseases. He has been a Medical Volunteer in several Latin American countries and currently volunteers with Mobile Medical Clinics of Greater Washington, D.C., where he serves at its Executive Board with the mission of providing free medical care to the underserved community of Washington. Dr. Picone also serves as a Board Member of Operation Canasta, supporting schools and orphanages in Argentina's hinterland. Dr. Picone is a partner in private practice with Chevy Chase Pulmonary Associates. His major professional interests include: Pulmonary Arterial Hypertension - Pathophysiology and Treatment. Bioethics and End-of-Life Decision Making. Parenchymal Lung Diseases. Dr. Picone has overseas experience in Europe, the Middle East, Central and South America. He also has an interest in literature, chess, squash and astronomy. Selected Publications Medical Complications of Cocaine: Possible relationship to low plasma cholinesterase enzyme. Om A; Ellahham S; Picone C; Ornato JP. Am Heart J 1993 Apr;125(4):1114-8. One of the Many Faces of Systemic Mastocytosis: Hemodynamic collapse. Abstract presentation - Clinical Vignettes. American College of Physicians Meeting-1994. Non-Resolving Pneumonia. Picone, C. Chest 1998; 114:923-926. Recurrent acute respiratory distress syndrome from use of salicylate containing over-the-counter preparations. Picone, C. Chest 1998; 114:408-S. Acute Pneumonitis after In-Vitro Fertilization with IM Progesterone. Picone C. JResp Dis 2008; 29:170-71. Opening Debate on End-of-Life Medical Care. Progress Notes. Suburban Hospital 2010 Palliative Care and Opening Debate on End-of-Life Medical Care. Sibley MD March 2010 Subacute Dyspnea, Hypoxemia and Refractory Cardiopulmonary Collapse – Postgraduate Education Corner. CHEST 2012;141(4):1106-9. Dr. Picone is rated as an Experienced provider by MediFind in the treatment of Vitamin B12 Deficiency. His top areas of expertise are Vitamin D Deficiency, Hyperventilation, Lung Nodules, and Lung Metastases.

Dr. Frederick P. Smith is a medical oncologist specializing in breast cancer at Sibley Memorial Hospital and an instructor at Johns Hopkins School of Medicine and Georgetown University School of Medicine. He has a private practice in Washington, D.C. He is affiliated with Sibley Memorial Hospital and Suburban Hospital. Dr. Smith earned his medical degree from Saint Louis University School of Medicine. He completed a residency in internal medicine at Georgetown University Hospital, followed by a fellowship in oncology. Dr. Smith was named a 2012 Top Doctor in the Washington, D.C., Baltimore and Washington-Baltimore areas by Castle Connolly, as well as a Top MD by Consumers’ Checkbook Magazine. Prior to joining Johns Hopkins, Dr. Smith was the director of extramural oncology research at Georgetown University. In this position, he contributed over 50 articles to peer-reviewed medical journals. Dr. Smith is an integral advocate in the community for promoting access to clinical research. He has also contributed to clinical trials. Dr. Smith is rated as an Experienced provider by MediFind in the treatment of Vitamin B12 Deficiency. His top areas of expertise are Breast Cancer, Paget Disease of the Breast, Ovarian Carcinosarcoma, and Virilizing Ovarian Tumor.

Dr. Joseph A. Vassallo is a cardiologist affiliated with Sibley Memorial Hospital and Suburban Hospital. He practices out of Cardiology and Internal Medicine, located in Chevy Chase, Maryland. Dr. Vassallo has expertise in cardiovascular disease, arrhythmia evaluation and internal medicine. Dr. Vassallo earned his medical degree from State University of New York at Buffalo School of Medicine. He completed a residency in internal medicine at New England Medical Center. Dr. Vassallo is a fellow of the American College of Cardiology. Dr. Vassallo is rated as an Experienced provider by MediFind in the treatment of Vitamin B12 Deficiency. His top areas of expertise are Heart Murmurs, Hypertension, Glucocorticoid-Remediable Aldosteronism, and High Cholesterol.

Dr. Sandra J. Ginsberg is a medical oncologist affiliated with Sibley Memorial Hospital, Georgetown University Hospital and George Washington University Hospital. She practices out of Drs. Adelson and Ginsberg in Washington, D.C. Dr. Ginsberg earned her medical degree at the University of Chicago Pritzker School of Medicine. She completed a residency in internal medicine at the State University of New York Health Science Center at Syracuse, followed by a fellowship in medical oncology at the University of Washington and a fellowship in hematology at the State University of New York Health Science Center at Syracuse. Dr. Ginsberg is rated as an Experienced provider by MediFind in the treatment of Vitamin B12 Deficiency. Her top areas of expertise are Vitamin D Deficiency, Inflammatory Breast Cancer, Paget Disease of the Breast, and Breast Cancer.

Dr. Jonathan M. Koff is a gastroenterologist affiliated with Sibley Memorial Hospital and Washington Hospital Center. Dr. Koff practices out of Capital Digestive Care’s Metropolitan Gastroenterology Group, located in Washington, D.C. and Chevy Chase, Md. Dr. Koff has an expertise in esophageal disease and colon cancer detection and screening, in addition to general gastroenterology. Dr. Koff earned his undergraduate degree from Wesleyan University and his medical degree from Boston University School of Medicine. He completed a residency in internal medicine at Walter Reed National Military Medical Center, where he went on to complete a fellowship in gastroenterology. Dr. Koff served in the United States Army for 11 years, working as an internist at the Army clinic in the Pentagon, as a first responder on 9-11 and on a tour in Iraq at the 31st Combat Support Hospital in Mosul. Dr. Koff also went on to direct the Center for Liver Disease and the Inflammatory Bowel Disease Clinic at Walter Reed Army Medical Center, where he served as the director of clinical research in gastroenterology as well. He also completed the first double balloon enteroscopy in the United States Army and in Washington, D.C. Dr. Koff is a member of the American College of Gastroenterology. He is on Sibley Memorial Hospital’s Emergency Room Committee and Internal Medicine Peer Review Committee. Dr. Koff has been named a Top MD by Washingtonian Magazine. Dr. Koff has contributed to various publications and presentation on gastroenterology. Dr. Koff is rated as an Experienced provider by MediFind in the treatment of Vitamin B12 Deficiency. His top areas of expertise are Crohn's Disease, Ulcerative Colitis, Eosinophilic Colitis, Endoscopy, and Gastrectomy.

Dr. Kathryn E. Kirk is a gastroenterologist affiliated with Sibley Memorial Hospital, George Washington University Hospital, Washington Hospital Center and the University of Maryland Baltimore Washington Medical Center. She practices out of Capital Digestive Care’s Metropolitan Gastroenterology Group in Washington, D.C., Chevy Chase, Md. and Bethesda, Md. Dr. Kirk has an expertise in gastroesophageal reflux disease, colorectal cancer screening and irritable bowel syndrome. She has special interests in colon cancer screening and prevention, celiac disease and eosinophilic esophagitis. Dr. Kirk earned her undergraduate degree from Princeton University and her medical degree from Weill Medical College of Cornell University. She completed a residency in internal medicine at Beth Israel Medical Center, followed by fellowships in hepatology and gastroenterology at Mount Sinai Hospital. Dr. Kirk is a member of the American College of Gastroenterology, the American Society for Gastrointestinal Endoscopy, the Crohn’s and Colitis Foundation of America and the American Gastroenterological Association. Dr. Kirk has been consistently recognized as a Top Doctor by Washingtonian magazine. Dr. Kirk is rated as an Experienced provider by MediFind in the treatment of Vitamin B12 Deficiency. Her top areas of expertise are Crohn's Disease, Ulcerative Colitis, Gastroesophageal Reflux Disease (GERD), and Eosinophilic Colitis.

Samuel Kallus is a Gastroenterologist in Chevy Chase, Maryland. Dr. Kallus is rated as an Experienced provider by MediFind in the treatment of Vitamin B12 Deficiency. His top areas of expertise are Crohn's Disease, Ulcerative Colitis, Eosinophilic Colitis, Endoscopy, and Colonoscopy.

Dr. Dennis A. Cullen is an internist affiliated with Sibley Memorial Hospital. He practices out of Cullen, Umosella, Cullen & Cullen in Bethesda, Md. and Oxon Hill, Md. Dr. Cullen earned his medical degree from Georgetown University School of Medicine. He completed a residency in internal medicine at Georgetown University Hospital. Dr. Cullen has been named a Top MD by Consumers’ Checkbook Magazine, as well as a Top Family/General Practitioner and a Top Internist by Washingtonian Magazine. Recent News Articles and Media Coverage The Brothers Cullen. Bethesda Magazine (January/February 2008). Dr. Cullen is rated as an Experienced provider by MediFind in the treatment of Vitamin B12 Deficiency. His top areas of expertise are Multiple Carboxylase Deficiency, Vitamin B12 Deficiency Anemia, Folate Deficiency, and Subacute Combined Degeneration.

Dr. Collin D. Cullen is an internist affiliated with Sibley Memorial Hospital. He practices out of Cullen, Umosella, Cullen & Cullen in Bethesda, Md. Dr. Cullen earned his medical degree from Georgetown University School of Medicine. He completed a residency in obstetrics and gynecology at Geisinger Medical Center. Dr. Cullen has been named a Top MD by Consumers’ Checkbook Magazine, as well as a Top Family/General Practitioner by Washingtonian Magazine. Recent News Articles and Media Coverage The Brothers Cullen. Bethesda Magazine (January/February 2008). Dr. Cullen is rated as an Experienced provider by MediFind in the treatment of Vitamin B12 Deficiency. His top areas of expertise are Tension Headache, Subacute Combined Degeneration, Cirrhosis, and Familial Combined Hyperlipidemia.

Hooman Azmi is a primary care provider, practicing in Family Medicine in Rockville, Maryland. Dr. Azmi is rated as an Experienced provider by MediFind in the treatment of Vitamin B12 Deficiency. His top areas of expertise are Anemia, Diabetic Hyperglycemic Hyperosmolar Syndrome, Parkinson's Disease, Thalamotomy, and Deep Brain Stimulation.

Nicholas Farrell is a Hematologist Oncology provider in Bethesda, Maryland. Dr. Farrell is rated as an Experienced provider by MediFind in the treatment of Vitamin B12 Deficiency. His top areas of expertise are Lung Cancer, Childhood Iron Deficiency Anemia, Pleuropulmonary Blastoma, and Iron Deficiency Anemia.

"Dr. Ari D. Fishman is a hematologist affiliated with Sibley Memorial Hospital, Holy Cross Hospital and George Washington University Hospital, where he serves as an assistant professor of medicine for the School of Medicine. He practices out of Maryland Oncology and Hematology, located in Wheaton, Maryland and Silver Spring, Maryland. Dr. Fishman earned his medical degree from Sackler School of Medicine. He completed a residency in internal medicine at the Beth Israel Medical Center, followed by a fellowship in hematology and oncology at the Montefiore Medical Center. Dr. Fishman previously worked at Washington Oncology Hematology Center, located in Washington, D.C. and Chevy Chase, Maryland. Dr. Fishman has been named a Top Doctor in Hematology and Oncology by Washingtonian Magazine and a Top Doctor by Consumers’ Checkbook magazine. Dr. Fishman is a member of the American College of Physicians and the American Society of Clinical Oncology. Dr. Fishman has contributed to numerous publications. Selected Publications Fishman AD, Hoffman A, Volterra F, Frymus M, Gentilluci M. ""Intracaval and intracardiac metastatic nonseminomatous germ cell tumor: a rare cause of hemolytic anemia and thrombocytopenia."" Cancer Invest. 2002;20(7-8):996-1001.". Dr. Fishman is rated as an Experienced provider by MediFind in the treatment of Vitamin B12 Deficiency. His top areas of expertise are Schnitzler Syndrome, Monoclonal Gammopathy of Undetermined Significance (MGUS), Myelodysplastic Syndrome (MDS), and Childhood Iron Deficiency Anemia.

Dr. John Merendino is an endocrinologist in Bethesda, MD. He is co-author of the New York Times bestseller, The Best Life Guide to Managing Diabetes and Pre-Diabetes. Dr. Merendino runs a busy private practice and does consulting for both private industry and government. He is an Assistant Clinical Professor at the George Washington University School of Medicine and is Chief of the Endocrine Section at Suburban Hospital, Johns Hopkins Medicine. Dr. Merendino is rated as an Experienced provider by MediFind in the treatment of Vitamin B12 Deficiency. His top areas of expertise are Maturity Onset Diabetes of the Young, Type 2 Diabetes (T2D), Hyperthyroidism, and Obesity in Children.