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Leonard J. Horwitz, MD, is on Staff in the Department of Hematologic Oncology & Blood Disorders at Cleveland Clinic's main campus. He accepted that appointment in 2007. He had been an assistant professor of medicine in the Section of Bone Marrow Transplantation at M. D. Anderson Hospital in Houston, Texas from 1984 to 1989. He thereafter entered private practice in hematology/oncology in Cincinnati, Ohio until coming to Cleveland Clinic. He served as director of the bone marrow transplant unit for Jewish Hospital of Cincinnati from 1989 to 2003.
His clinical interest lies in non-malignant blood disorders. He no longer does bone marrow transplants.
He graduated magna cum laude from Yale University in New Haven, Conn., and received his medical degree from Albert Einstein College of Medicine, Bronx, N.Y. He completed a residency in internal medicine and fellowship in hematology at Long Island Jewish Hospital, New Hyde Park, N.Y. Dr. Horwitz completed a second fellowship in medical oncology at MD Anderson Hospital & Tumor Institute in Houston, Texas. He is licensed to practice medicine in Ohio.
Dr. Horwitz is a member of the American Medical Association, American College of Physicians (fellow) and American Society of Clinical Oncology, among others. He is board-certified in hematology and in medical oncology and by the American Board of Internal Medicine.
Benign hematologic disorders, coagulation disorders, monoclonal gammopathy of undetermined significance (MGUS), multiple myeloma, leukemia, cancer, myelodysplastic syndrome, MDS, anemia
Awards & Honors
Fellow of the American College of Physicians
American Society of Hematology
American Society of Clinical Oncology
American College of Physicians
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As of 2/4/2013, Dr. Horwitz has reported no financial relationship with industry that is applicable to this listing. In general, patients should feel free to contact their doctor about any of the relationships and how the relationships are overseen by the Cleveland Clinic. To learn more about the Cleveland Clinic's policies on collaborations with industry and innovation management, go to our Integrity in Innovation page.
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