Dr. Juan Rosai was born "Giovanni" Rosai in Poppi, a small town in the Tuscan hills, near Florence, Italy. At the age of 8 years he emigrated with his family to Argentina, where he became "Juan". He received his M.D. degree from the University of Buenos Aires in 1961, began his postgraduate training in Pathology in Mar del Plata under the tutelage of Dr. Eduardo Lascano, emigrated to the United States in 1965, and completed his training in Surgical Pathology under the legendary Lauren V. Ackerman at Barnes Hospital and Washington University ( St. Louis) in 1967.

His past and present professional appointments include those of

• Instructor/Assistant Professor/Associate Professor of Pathology at Washington University (St. Louis) in 1967-1974,
• Professor of Pathology and Director of Anatomic Pathology at the University of Minnesota (Minneapolis) in 1974-85,
• Professor of Pathology and Director of Anatomic Pathology at Yale University (New Haven) in 1985-91,
• Chairman of the Department of Pathology at Memorial Sloan-Kettering Cancer Center (New York) in 1991-1999,
• Chairman of the Pathology Department at the National Cancer Institute, Milan, Italy in 2000-05,
• Adjunct Professor of Pathology at Cornell University, New York (currently held)
• and Visiting Professor of the Department of Pathology of Massachusetts General Hospital and Harvard University, Boston (currently held).

He is presently the Director of the International Center of Oncologic Pathology Consultation Center at the Centro Diagnostico Italiano (C.D.I.), in Milan, Italy, and Consultant Pathologist at Genzyme Genetics (New York).

He is a Life Trustee of the American Board of Pathology, Co-founder and past Chairman of the Association of Directors of Anatomic and Surgical Pathology, Editor-in-Chief of the Third Series Atlas of Tumor Pathology, Editor-in-Chief of The International Journal of Surgical Pathology, and member of over 20 pathology organizations.

He is the author of Rosai and Ackerman's Surgical Pathology, currently in its tenth edition. He is also the author (with the late Gerald Levine) of the 2nd Series A.F.I.P. Fascicle on Tumors of the Thymus, the author (with Maria Luisa Carcangiu and Ronald DeLellis) of the 3rd Series A.F.I.P. Fascicle on Tumors of the Thyroid, the Editor of the Second Edition of the W.H.O. book on Histologic Classification of Thymic Tumors, and the editor of the book "Guiding the surgeon's hand. The History of American Surgical Pathology". In addition, he is the author of over 300 publications which include original articles, reviews, and essays.

He has received Doctor Honoris Causa Degrees from the University of Bologna (Italy), the University of Santiago de Compostela (Spain), the University of Ioannina (Greece) and the University of Cordoba (Argentina). He has also been awarded an Honorary Fellowship by the Royal College of Pathologists (England), a Honorary Life Membership of the Association of Clinical Pathologists (England), The Distinguished Pathologist Award of USCAP, the Golden Medal of the IAP, and has given the Maude Abbott Lecture at the US and Canadian Academy of Pathology. He has described several new entities, one in collaboration with Ronald Dorfman and which carries their names.

学术很了不起的一个教授，国外有一个专门的网站用于讨论和展示他收集到的一些病例，他也是众所周知的陈国璋教授的老师之一。