An affiliate of the American Society of Clinical Oncology - Learn More

Circle of Honor Ironwood Physicians Emeritus

Welcome to our Circle of Honor page for Ironwood Cancer & Research Centers Physicians Emeritus.  Our staff and patients love working with our physicians.  Ironwood Physicians are some of the most dedicated, kind, and outstanding individuals we’ve ever known.  Sometimes, after long and distinguished careers in Oncology, some of our physicians retire.   We thank them for years of service to their patients and to the pursuit of excellence.   We hope that they will continue to grace us with their presence from time to time.

Harrison J. Bachrach, MD

Dr. Harrison Bachrach was born and raised in a farming community on eastern Long Island. He graduated with honors from the State University of New York Buffalo School of Medicine, completed his Internal Medicine training at the University of Pittsburgh and his Oncology & Hematology training at the Roswell Park Cancer Institute.  Dr. Bachrach was part of Desert Oncology from 1988 until 2012 when he joined Ironwood Cancer & Research Centers where he practiced until his retirement in 2018.  One of his partners, Dr. Michael Long recalls, “Dr. Bachrach was a deep sea enthusiast and loved to celebrate Mardi Gras.  He’s been a great oncologist to work with.”  In retirement he plans to continue his interest and involvement in the performing and visual arts. We express our sincere appreciation to Dr. Bachrach for his example of unyielding service and dedication to his patients and the oncology community.  We proudly welcome him into Ironwood’s Circle of Honor.

Marvin M. Chassin, MD

Dr. Marvin Chassin spent nearly forty years practicing medical oncology in the East Valley. After graduating from Yale University School of Medicine, he trained at the National Cancer Institute of the National Institutes of Health where he was involved in clinical and drug development research. Dr. Chassin was a founding member of Desert Oncology.  He joined Ironwood Cancer & Research Centers in 2012 where his patients and staff were lucky enough to be in his presence until his much deserved retirement. Colleague, Dr. Clayton Polowy, said “Dr. Chassin provided diligent and steadfast care to thousands of patients for over 30 years in the East Valley.  He was always available to his colleagues to provide expert advice and consultation.  He was a trusted leader, a loyal friend and true professional.”

Nathaniel A. Fastenberg, MD

For 35 years, Dr. Nathaniel Fastenberg has been well known in the Valley’s oncology community. He completed a fellowship at M.D. Anderson Hospital and Tumor Institute in Houston, TX.  Additionally, he practiced in southeast Maricopa County from 1983 until joining Ironwood Cancer & Research Centers in 2006.  Dr. Fastenberg was involved in several research studies throughout the years to make sure his patients got the most advanced treatments possible. Ironwood colleague Dr. Mark Ono said, “Dr. Fastenberg was an excellent clinician with a subtle, dry humor.  I’ll miss working with him.”  The patients and staff of Ironwood Cancer and Research Centers wish him the very best in his retirement.

Jeffrey D. Isaacs, M.D.

Dr. Jeffrey Isaacs was listed as a Top Doctor with Phoenix Magazine for over 20 years.  His 35 year dedication and expertise in the practice of Medical Oncology and Hematology is renowned. In 1981, he joined Hematology Associates and was a managing partner with Arizona Oncology. Colleague Dr. Kukunoor said, “My education taught me the science but Dr. Isaacs taught me the ‘art’ of practicing oncology.” From 2003-2013, Dr. Isaacs continued his vision with Southwest Hematology and Oncology. He was the co-principal investigator for the Clinical Community Oncology Program, bringing many research clinical trials to the Valley. Dr. Ewing said, “Dr. Isaacs is revered by his patients and will remain a visionary in oncology. He has an inquisitive mind and a humble soul that is rarely seen in one of such greatness.” Dr. Isaacs merged with Ironwood Cancer & Research Centers until his retirement.

Jon Paul Rubach, MD

Dr. Rubach graduated from the University of Notre Dame Law School and the SUNY Buffalo School of Medicine.  In 1976, he moved to Mesa where he established Desert Oncology, the first oncology practice in the East Valley. Dr. Parvinderjit Khanuja recalls, “Dr. Rubach pioneered healthcare and oncology in the East Valley.  When I started in oncology 25 years ago, he was my mentor and role model that I looked up to.”  He served as Chief of Staff at Desert Samaritan and as Desert Samaritan’s representative to the American Medical Association.  The oncology practice he created merged with his long time colleagues at Ironwood Cancer & Research Centers in 2012.  Christine, who was his friend and patient, said “He was a great doctor.  I always came out of the exam room feeling better than I did when I came in.  He made each patient feel like they were his only patient.”  He loved his weekly golf outings and trips to San Diego with his family. He was an avid supporter and assistant coach for his children’s baseball and soccer teams.  Colleague, Dr. Clayton Polowy, said “Dr. Rubach was gregarious, sincere, affable, and treated his patients like family.”  Although Dr. Rubach passed away in 2012, his legacy lives on with the patients and staff that were lucky enough to work along his side.  Dr. Rubach’s contributions to the field of oncology and to the community will never be forgotten.